api: return allocated string in hook_info callback and function info_get

54 files changed, 724 insertions, 526 deletions

diff --git a/ChangeLog.adoc b/ChangeLog.adoc
index a2fd53c31..44801ddf9 100644
--- a/ChangeLog.adoc
+++ b/ChangeLog.adoc
@@ -23,6 +23,7 @@ New features::
   * core: use seconds by default in /repeat interval, allow unit for the interval
   * core: allow text in addition to a command in command /repeat
   * core: add option "addreplace" in command /filter (issue #1055, issue #1312)
+  * api: return allocated string in hook_info callback and function info_get
   * api: replace argument "keep_eol" by "flags" in function string_split (issue #1322)
   * api: add function command_options (issue #928)
   * api: add function string_match_list
diff --git a/ReleaseNotes.adoc b/ReleaseNotes.adoc
index 156987c47..9398f84be 100644
--- a/ReleaseNotes.adoc
+++ b/ReleaseNotes.adoc
@@ -20,6 +20,17 @@ https://weechat.org/files/changelog/ChangeLog-devel.html[ChangeLog]
 [[v2.5]]
 == Version 2.5 (under dev)
 
+[[v2.5_hook_info_allocated_string]]
+=== Allocated string in hook info and function info_get
+
+The hook info callback now returns an allocated string, which must be freed
+after use (in previous versions, a pointer to a static string was returned).
+
+Consequently, the function info_get returns an allocated string, which must
+be freed after use.
+
+This affects only C code, no changes are required in scripts.
+
 [[v2.5_xfer_option_speed_limit]]
 === Speed limit option for DCC files
 
diff --git a/doc/en/weechat_plugin_api.en.adoc b/doc/en/weechat_plugin_api.en.adoc
index d330aa5c6..840b98ada 100644
--- a/doc/en/weechat_plugin_api.en.adoc
+++ b/doc/en/weechat_plugin_api.en.adoc
@@ -11267,7 +11267,7 @@ weechat.hook_modifier_exec("my_modifier", my_data, my_string)
 
 ==== hook_info
 
-_Updated in 1.5._
+_Updated in 1.5, 2.5._
 
 Hook an information (callback takes and returns a string).
 
@@ -11278,10 +11278,10 @@ Prototype:
 struct t_hook *weechat_hook_info (const char *info_name,
                                   const char *description,
                                   const char *args_description,
-                                  const char *(*callback)(const void *pointer,
-                                                          void *data,
-                                                          const char *info_name,
-                                                          const char *arguments),
+                                  char *(*callback)(const void *pointer,
+                                                    void *data,
+                                                    const char *info_name,
+                                                    const char *arguments),
                                   const void *callback_pointer,
                                   void *callback_data);
 ----
@@ -11307,16 +11307,20 @@ Return value:
 
 * pointer to new hook, NULL if error occurred
 
+[NOTE]
+With WeeChat ≥ 2.5, the callback returns an allocated string
+(with WeeChat ≤ 2.4, it was a pointer to a static string).
+
 C example:
 
 [source,C]
 ----
-const char *
+char *
 my_info_cb (const void *pointer, void *data, const char *info_name,
             const char *arguments)
 {
     /* ... */
-    return pointer_to_string;
+    return strdup ("some_info");
 }
 
 /* add info "my_info" */
@@ -14589,13 +14593,15 @@ Functions to get infos.
 
 ==== info_get
 
+_Updated in 2.5._
+
 Return info, as string, from WeeChat or a plugin.
 
 Prototype:
 
 [source,C]
 ----
-const char *weechat_info_get (const char *info_name, const char *arguments);
+char *weechat_info_get (const char *info_name, const char *arguments);
 ----
 
 Arguments:
@@ -14608,6 +14614,10 @@ Return value:
 
 * string with info asked, NULL if an error occurred
 
+[NOTE]
+With WeeChat ≥ 2.5, the value returned is an allocated string
+(with WeeChat ≤ 2.4, it was a pointer to a static string).
+
 Infos:
 
 include::autogen/plugin_api/infos.adoc[]
@@ -14616,11 +14626,19 @@ C example:
 
 [source,C]
 ----
+char *version = weechat_info_get ("version", NULL);
+char *date = weechat_info_get ("date", NULL);
 weechat_printf (NULL, "Current WeeChat version is: %s (compiled on %s)",
-                weechat_info_get ("version", NULL),
-                weechat_info_get ("date", NULL));
-weechat_printf (NULL, "WeeChat home is: %s",
-                weechat_info_get ("weechat_dir", NULL));
+                version, date);
+if (version)
+    free (version);
+if (date)
+    free (date);
+
+char *weechat_dir = weechat_info_get ("weechat_dir", NULL);
+weechat_printf (NULL, "WeeChat home is: %s", weechat_dir);
+if (weechat_dir)
+    free (weechat_dir);
 ----
 
 Script (Python):
diff --git a/doc/fr/weechat_plugin_api.fr.adoc b/doc/fr/weechat_plugin_api.fr.adoc
index 54092008b..3df7bc2d8 100644
--- a/doc/fr/weechat_plugin_api.fr.adoc
+++ b/doc/fr/weechat_plugin_api.fr.adoc
@@ -11507,7 +11507,7 @@ weechat.hook_modifier_exec("mon_modifier", mes_donnees, ma_chaine)
 
 ==== hook_info
 
-_Mis à jour dans la 1.5._
+_Mis à jour dans la 1.5, 2.5._
 
 Accrocher une information (la fonction de rappel prend et retourne une chaîne).
 
@@ -11518,10 +11518,10 @@ Prototype :
 struct t_hook *weechat_hook_info (const char *info_name,
                                   const char *description,
                                   const char *args_description,
-                                  const char *(*callback)(const void *pointer,
-                                                          void *data,
-                                                          const char *info_name,
-                                                          const char *arguments),
+                                  char *(*callback)(const void *pointer,
+                                                    void *data,
+                                                    const char *info_name,
+                                                    const char *arguments),
                                   const void *callback_pointer,
                                   void *callback_data);
 ----
@@ -11551,16 +11551,20 @@ Valeur de retour :
 
 * pointeur vers le nouveau "hook", NULL en cas d'erreur
 
+[NOTE]
+Avec WeeChat ≥ 2.5, la fonction de rappel renvoie une chaîne allouée
+(avec WeeChat ≤ 2.4, il s'agissait d'un pointeur vers une chaîne statique).
+
 Exemple en C :
 
 [source,C]
 ----
-const char *
+char *
 my_info_cb (const void *pointer, void *data, const char *info_name,
             const char *arguments)
 {
     /* ... */
-    return pointeur_vers_chaine;
+    return strdup ("some_info");
 }
 
 /* ajoute l'information "mon_info" */
@@ -14904,13 +14908,15 @@ Fonctions pour obtenir des informations.
 
 ==== info_get
 
+_Mis à jour dans la 2.5._
+
 Retourner une information, sous forme de chaîne, de WeeChat ou d'une extension.
 
 Prototype :
 
 [source,C]
 ----
-const char *weechat_info_get (const char *info_name, const char *arguments);
+char *weechat_info_get (const char *info_name, const char *arguments);
 ----
 
 Paramètres :
@@ -14923,6 +14929,10 @@ Valeur de retour :
 
 * chaîne avec l'information demandée, NULL en cas d'erreur
 
+[NOTE]
+Avec WeeChat ≥ 2.5, la valeur retournée est une chaîne allouée
+(avec WeeChat ≤ 2.4, il s'agissait d'un pointeur vers une chaîne statique).
+
 Infos :
 
 include::autogen/plugin_api/infos.adoc[]
@@ -14931,11 +14941,19 @@ Exemple en C :
 
 [source,C]
 ----
+char *version = weechat_info_get ("version", NULL);
+char *date = weechat_info_get ("date", NULL);
 weechat_printf (NULL, "La version de WeeChat est : %s (compilée le %s)",
-                weechat_info_get ("version", NULL),
-                weechat_info_get ("date", NULL));
-weechat_printf (NULL, "Le répertoire de WeeChat est : %s",
-                weechat_info_get ("weechat_dir", NULL));
+                version, date);
+if (version)
+    free (version);
+if (date)
+    free (date);
+
+weechat_dir = weechat_info_get ("weechat_dir", NULL);
+weechat_printf (NULL, "Le répertoire de WeeChat est : %s", weechat_dir);
+if (weechat_dir)
+    free (weechat_dir);
 ----
 
 Script (Python) :
diff --git a/doc/it/weechat_plugin_api.it.adoc b/doc/it/weechat_plugin_api.it.adoc
index dbdf78ca5..ff29620cf 100644
--- a/doc/it/weechat_plugin_api.it.adoc
+++ b/doc/it/weechat_plugin_api.it.adoc
@@ -11723,7 +11723,7 @@ weechat.hook_modifier_exec("my_modifier", my_data, my_string)
 ==== hook_info
 
 // TRANSLATION MISSING
-_Updated in 1.5._
+_Updated in 1.5, 2.5._
 
 Hook su una informazione (la callback prende e restituisce una stringa).
 
@@ -11734,10 +11734,10 @@ Prototipo:
 struct t_hook *weechat_hook_info (const char *info_name,
                                   const char *description,
                                   const char *args_description,
-                                  const char *(*callback)(const void *pointer,
-                                                          void *data,
-                                                          const char *info_name,
-                                                          const char *arguments),
+                                  char *(*callback)(const void *pointer,
+                                                    void *data,
+                                                    const char *info_name,
+                                                    const char *arguments),
                                   const void *callback_pointer,
                                   void *callback_data);
 ----
@@ -11766,16 +11766,21 @@ Valore restituito:
 
 * puntatore al nuovo hook, NULL in caso di errore
 
+// TRANSLATION MISSING
+[NOTE]
+With WeeChat ≥ 2.5, the callback returns an allocated string
+(with WeeChat ≤ 2.4, it was a pointer to a static string).
+
 Esempio in C:
 
 [source,C]
 ----
-const char *
+char *
 my_info_cb (const void *pointer, void *data, const char *info_name,
             const char *arguments)
 {
     /* ... */
-    return pointer_to_string;
+    return strdup ("some_info");
 }
 
 /* aggiunge informazione "my_info" */
@@ -15180,13 +15185,16 @@ Funzioni per ottenere info.
 
 ==== info_get
 
+// TRANSLATION MISSING
+_Updated in 2.5._
+
 Restituisce la info, come stringa, da WeeChat o da un plugin.
 
 Prototipo:
 
 [source,C]
 ----
-const char *weechat_info_get (const char *info_name, const char *arguments);
+char *weechat_info_get (const char *info_name, const char *arguments);
 ----
 
 Argomenti:
@@ -15201,6 +15209,11 @@ Valore restituito:
 * stringa con l'informazione richiesta, NULL in caso di errore
 
 // TRANSLATION MISSING
+[NOTE]
+With WeeChat ≥ 2.5, the value returned is an allocated string
+(with WeeChat ≤ 2.4, it was a pointer to a static string).
+
+// TRANSLATION MISSING
 Infos:
 
 include::autogen/plugin_api/infos.adoc[]
@@ -15209,11 +15222,19 @@ Esempio in C:
 
 [source,C]
 ----
+char *version = weechat_info_get ("version", NULL);
+char *date = weechat_info_get ("date", NULL);
 weechat_printf (NULL, "Current WeeChat version is: %s (compiled on %s)",
-                weechat_info_get ("version", NULL),
-                weechat_info_get ("date", NULL));
-weechat_printf (NULL, "WeeChat home is: %s",
-                weechat_info_get ("weechat_dir", NULL));
+                version, date);
+if (version)
+    free (version);
+if (date)
+    free (date);
+
+char *weechat_dir = weechat_info_get ("weechat_dir", NULL);
+weechat_printf (NULL, "WeeChat home is: %s", weechat_dir);
+if (weechat_dir)
+    free (weechat_dir);
 ----
 
 Script (Python):
diff --git a/doc/ja/weechat_plugin_api.ja.adoc b/doc/ja/weechat_plugin_api.ja.adoc
index 59190dff2..0c059b649 100644
--- a/doc/ja/weechat_plugin_api.ja.adoc
+++ b/doc/ja/weechat_plugin_api.ja.adoc
@@ -11229,7 +11229,7 @@ weechat.hook_modifier_exec("my_modifier", my_data, my_string)
 
 ==== hook_info
 
-_WeeChat バージョン 1.5 で更新。_
+_WeeChat バージョン 1.5, 2.5 で更新。_
 
 インフォをフック (コールバックを呼び出し、文字列を返す)。
 
@@ -11240,10 +11240,10 @@ _WeeChat バージョン 1.5 で更新。_
 struct t_hook *weechat_hook_info (const char *info_name,
                                   const char *description,
                                   const char *args_description,
-                                  const char *(*callback)(const void *pointer,
-                                                          void *data,
-                                                          const char *info_name,
-                                                          const char *arguments),
+                                  char *(*callback)(const void *pointer,
+                                                    void *data,
+                                                    const char *info_name,
+                                                    const char *arguments),
                                   const void *callback_pointer,
                                   void *callback_data);
 ----
@@ -11269,16 +11269,21 @@ struct t_hook *weechat_hook_info (const char *info_name,
 
 * 新しいフックへのポインタ、エラーが起きた場合は NULL
 
+// TRANSLATION MISSING
+[NOTE]
+With WeeChat ≥ 2.5, the callback returns an allocated string
+(with WeeChat ≤ 2.4, it was a pointer to a static string).
+
 C 言語での使用例:
 
 [source,C]
 ----
-const char *
+char *
 my_info_cb (const void *pointer, void *data, const char *info_name,
             const char *arguments)
 {
     /* ... */
-    return pointer_to_string;
+    return strdup ("some_info");
 }
 
 /* add info "my_info" */
@@ -14549,13 +14554,15 @@ else
 
 ==== info_get
 
+_WeeChat バージョン 2.5 で更新。_
+
 文字列型で WeeChat またはプラグインからのインフォを返す。
 
 プロトタイプ:
 
 [source,C]
 ----
-const char *weechat_info_get (const char *info_name, const char *arguments);
+char *weechat_info_get (const char *info_name, const char *arguments);
 ----
 
 引数:
@@ -14568,6 +14575,11 @@ const char *weechat_info_get (const char *info_name, const char *arguments);
 
 * 指定したインフォを含む文字列、エラーが起きた場合は NULL
 
+// TRANSLATION MISSING
+[NOTE]
+With WeeChat ≥ 2.5, the value returned is an allocated string
+(with WeeChat ≤ 2.4, it was a pointer to a static string).
+
 インフォ:
 
 include::autogen/plugin_api/infos.adoc[]
@@ -14576,11 +14588,19 @@ C 言語での使用例:
 
 [source,C]
 ----
+char *version = weechat_info_get ("version", NULL);
+char *date = weechat_info_get ("date", NULL);
 weechat_printf (NULL, "Current WeeChat version is: %s (compiled on %s)",
-                weechat_info_get ("version", NULL),
-                weechat_info_get ("date", NULL));
-weechat_printf (NULL, "WeeChat home is: %s",
-                weechat_info_get ("weechat_dir", NULL));
+                version, date);
+if (version)
+    free (version);
+if (date)
+    free (date);
+
+char *weechat_dir = weechat_info_get ("weechat_dir", NULL);
+weechat_printf (NULL, "WeeChat home is: %s", weechat_dir);
+if (weechat_dir)
+    free (weechat_dir);
 ----
 
 スクリプト (Python) での使用例:
diff --git a/src/core/hook/wee-hook-info.c b/src/core/hook/wee-hook-info.c
index 36d866c60..33aeb5694 100644
--- a/src/core/hook/wee-hook-info.c
+++ b/src/core/hook/wee-hook-info.c
@@ -83,14 +83,16 @@ hook_info (struct t_weechat_plugin *plugin, const char *info_name,
 
 /*
  * Gets info (as string) via info hook.
+ *
+ * Note: result must be freed after use.
  */
 
-const char *
+char *
 hook_info_get (struct t_weechat_plugin *plugin, const char *info_name,
                const char *arguments)
 {
     struct t_hook *ptr_hook, *next_hook;
-    const char *value;
+    char *value;
 
     /* make C compiler happy */
     (void) plugin;
diff --git a/src/core/hook/wee-hook-info.h b/src/core/hook/wee-hook-info.h
index ee4d621c3..b97ad7f9b 100644
--- a/src/core/hook/wee-hook-info.h
+++ b/src/core/hook/wee-hook-info.h
@@ -25,9 +25,9 @@ struct t_infolist_item;
 
 #define HOOK_INFO(hook, var) (((struct t_hook_info *)hook->hook_data)->var)
 
-typedef const char *(t_hook_callback_info)(const void *pointer, void *data,
-                                           const char *info_name,
-                                           const char *arguments);
+typedef char *(t_hook_callback_info)(const void *pointer, void *data,
+                                     const char *info_name,
+                                     const char *arguments);
 
 struct t_hook_info
 {
@@ -44,9 +44,9 @@ extern struct t_hook *hook_info (struct t_weechat_plugin *plugin,
                                  t_hook_callback_info *callback,
                                  const void *callback_pointer,
                                  void *callback_data);
-extern const char *hook_info_get (struct t_weechat_plugin *plugin,
-                                  const char *info_name,
-                                  const char *arguments);
+extern char *hook_info_get (struct t_weechat_plugin *plugin,
+                            const char *info_name,
+                            const char *arguments);
 extern void hook_info_free_data (struct t_hook *hook);
 extern int hook_info_add_to_infolist (struct t_infolist_item *item,
                                       struct t_hook *hook);
diff --git a/src/core/wee-eval.c b/src/core/wee-eval.c
index 2613fc501..ab4ed94da 100644
--- a/src/core/wee-eval.c
+++ b/src/core/wee-eval.c
@@ -520,7 +520,7 @@ eval_replace_vars_cb (void *data, const char *text)
     /* 10. info */
     if (strncmp (text, "info:", 5) == 0)
     {
-        ptr_value = NULL;
+        value = NULL;
         ptr_arguments = strchr (text + 5, ',');
         if (ptr_arguments)
         {
@@ -531,10 +531,10 @@ eval_replace_vars_cb (void *data, const char *text)
             info_name = strdup (text + 5);
         if (info_name)
         {
-            ptr_value = hook_info_get (NULL, info_name, ptr_arguments);
+            value = hook_info_get (NULL, info_name, ptr_arguments);
             free (info_name);
         }
-        return strdup ((ptr_value) ? ptr_value : "");
+        return (value) ? value : strdup ("");
     }
 
     /* 11. current date/time */
diff --git a/src/plugins/charset/charset.c b/src/plugins/charset/charset.c
index a36b2c7d5..3546259f8 100644
--- a/src/plugins/charset/charset.c
+++ b/src/plugins/charset/charset.c
@@ -50,8 +50,8 @@ struct t_config_option *charset_default_encode = NULL;
 struct t_config_section *charset_config_section_decode = NULL;
 struct t_config_section *charset_config_section_encode = NULL;
 
-const char *charset_terminal = NULL;
-const char *charset_internal = NULL;
+char *charset_terminal = NULL;
+char *charset_internal = NULL;
 
 
 /*
@@ -641,5 +641,10 @@ weechat_plugin_end (struct t_weechat_plugin *plugin)
 
     weechat_config_free (charset_config_file);
 
+    if (charset_terminal)
+        free (charset_terminal);
+    if (charset_internal)
+        free (charset_internal);
+
     return WEECHAT_RC_OK;
 }
diff --git a/src/plugins/fifo/fifo-info.c b/src/plugins/fifo/fifo-info.c
index 286e85ae4..3039ee443 100644
--- a/src/plugins/fifo/fifo-info.c
+++ b/src/plugins/fifo/fifo-info.c
@@ -20,6 +20,7 @@
  */
 
 #include <stdlib.h>
+#include <string.h>
 
 #include "../weechat-plugin.h"
 #include "fifo.h"
@@ -29,7 +30,7 @@
  * Returns FIFO info "fifo_filename".
  */
 
-const char *
+char *
 fifo_info_info_fifo_filename_cb (const void *pointer, void *data,
                                  const char *info_name,
                                  const char *arguments)
@@ -40,7 +41,7 @@ fifo_info_info_fifo_filename_cb (const void *pointer, void *data,
     (void) info_name;
     (void) arguments;
 
-    return fifo_filename;
+    return (fifo_filename) ? strdup (fifo_filename) : NULL;
 }
 
 /*
diff --git a/src/plugins/fset/fset-option.c b/src/plugins/fset/fset-option.c
index 895b633e2..a18105e62 100644
--- a/src/plugins/fset/fset-option.c
+++ b/src/plugins/fset/fset-option.c
@@ -1522,7 +1522,7 @@ fset_option_config_cb (const void *pointer,
                        const char *option,
                        const char *value)
 {
-    const char *ptr_info;
+    char *info;
 
     /* make C compiler happy */
     (void) pointer;
@@ -1534,9 +1534,14 @@ fset_option_config_cb (const void *pointer,
         return WEECHAT_RC_OK;
 
     /* do nothing if WeeChat is upgrading */
-    ptr_info = weechat_info_get ("weechat_upgrading", NULL);
-    if (ptr_info && (strcmp (ptr_info, "1") == 0))
+    info = weechat_info_get ("weechat_upgrading", NULL);
+    if (info && (strcmp (info, "1") == 0))
+    {
+        free (info);
         return WEECHAT_RC_OK;
+    }
+    if (info)
+        free (info);
 
     /*
      * we limit the number of options to display with the timer; for example
diff --git a/src/plugins/guile/weechat-guile-api.c b/src/plugins/guile/weechat-guile-api.c
index 410eebe49..331ce0e64 100644
--- a/src/plugins/guile/weechat-guile-api.c
+++ b/src/plugins/guile/weechat-guile-api.c
@@ -57,8 +57,6 @@
     plugin_script_str2ptr (weechat_guile_plugin,                        \
                            GUILE_CURRENT_SCRIPT_NAME,                   \
                            guile_function_name, __string)
-#define API_STATIC_STRING(__string)                                     \
-    plugin_script_get_static_string(&guile_data, __string);
 #define API_SCM_TO_STRING(__str)                                        \
     weechat_guile_api_scm_to_string(__str,                              \
                                     guile_strings, &guile_num_strings)
@@ -2940,14 +2938,14 @@ weechat_guile_api_hook_modifier_exec (SCM modifier, SCM modifier_data,
     API_RETURN_STRING_FREE(result);
 }
 
-const char *
+char *
 weechat_guile_api_hook_info_cb (const void *pointer, void *data,
                                 const char *info_name,
                                 const char *arguments)
 {
     struct t_plugin_script *script;
     void *func_argv[3];
-    char empty_arg[1] = { '\0' }, *result;
+    char empty_arg[1] = { '\0' };
     const char *ptr_function, *ptr_data;
 
     script = (struct t_plugin_script *)pointer;
@@ -2959,12 +2957,10 @@ weechat_guile_api_hook_info_cb (const void *pointer, void *data,
         func_argv[1] = (info_name) ? (char *)info_name : empty_arg;
         func_argv[2] = (arguments) ? (char *)arguments : empty_arg;
 
-        result = (char *)weechat_guile_exec (script,
-                                             WEECHAT_SCRIPT_EXEC_STRING,
-                                             ptr_function,
-                                             "sss", func_argv);
-
-        return API_STATIC_STRING(result);
+        return (char *)weechat_guile_exec (script,
+                                           WEECHAT_SCRIPT_EXEC_STRING,
+                                           ptr_function,
+                                           "sss", func_argv);
     }
 
     return NULL;
@@ -4107,7 +4103,7 @@ weechat_guile_api_command_options (SCM buffer, SCM command, SCM options)
 SCM
 weechat_guile_api_info_get (SCM info_name, SCM arguments)
 {
-    const char *result;
+    char *result;
     SCM return_value;
 
     API_INIT_FUNC(1, "info_get", API_RETURN_EMPTY);
@@ -4117,7 +4113,7 @@ weechat_guile_api_info_get (SCM info_name, SCM arguments)
     result = weechat_info_get (API_SCM_TO_STRING(info_name),
                                API_SCM_TO_STRING(arguments));
 
-    API_RETURN_STRING(result);
+    API_RETURN_STRING_FREE(result);
 }
 
 SCM
diff --git a/src/plugins/guile/weechat-guile.c b/src/plugins/guile/weechat-guile.c
index 2d7e7653d..0ea420582 100644
--- a/src/plugins/guile/weechat-guile.c
+++ b/src/plugins/guile/weechat-guile.c
@@ -59,7 +59,6 @@ int guile_eval_mode = 0;
 int guile_eval_send_input = 0;
 int guile_eval_exec_commands = 0;
 struct t_gui_buffer *guile_eval_buffer = NULL;
-char *guile_eval_output = NULL;
 #define GUILE_EVAL_SCRIPT                                               \
     "(weechat:register \"" WEECHAT_SCRIPT_EVAL_NAME "\" \"\" \"1.0\" "  \
     "\"" WEECHAT_LICENSE "\" \"Evaluation of source code\" "            \
@@ -968,23 +967,23 @@ weechat_guile_hdata_cb (const void *pointer, void *data,
  * Returns guile info "guile_eval".
  */
 
-const char *
+char *
 weechat_guile_info_eval_cb (const void *pointer, void *data,
                             const char *info_name,
                             const char *arguments)
 {
+    char *output;
+
     /* make C compiler happy */
     (void) pointer;
     (void) data;
     (void) info_name;
 
     weechat_guile_eval (NULL, 0, 0, (arguments) ? arguments : "");
-    if (guile_eval_output)
-        free (guile_eval_output);
-    guile_eval_output = strdup (*guile_buffer_output);
+    output = strdup (*guile_buffer_output);
     weechat_string_dyn_copy (guile_buffer_output, NULL);
 
-    return guile_eval_output;
+    return output;
 }
 
 /*
@@ -1272,8 +1271,6 @@ weechat_plugin_end (struct t_weechat_plugin *plugin)
     if (guile_action_autoload_list)
         free (guile_action_autoload_list);
     weechat_string_dyn_free (guile_buffer_output, 1);
-    if (guile_eval_output)
-        free (guile_eval_output);
 
     return WEECHAT_RC_OK;
 }
diff --git a/src/plugins/irc/irc-color.c b/src/plugins/irc/irc-color.c
index 3a555caa8..366ebe40b 100644
--- a/src/plugins/irc/irc-color.c
+++ b/src/plugins/irc/irc-color.c
@@ -408,8 +408,7 @@ irc_color_encode (const char *string, int keep_colors)
 int
 irc_color_convert_rgb2irc (int rgb)
 {
-    char str_color[64], *error;
-    const char *info_color;
+    char str_color[64], *error, *info_color;
     long number;
 
     snprintf (str_color, sizeof (str_color),
@@ -419,16 +418,23 @@ irc_color_convert_rgb2irc (int rgb)
 
     info_color = weechat_info_get ("color_rgb2term", str_color);
     if (!info_color || !info_color[0])
+    {
+        if (info_color)
+            free (info_color);
         return -1;
+    }
 
     error = NULL;
     number = strtol (info_color, &error, 10);
     if (!error || error[0]
         || (number < 0) || (number >= IRC_COLOR_TERM2IRC_NUM_COLORS))
     {
+        free (info_color);
         return -1;
     }
 
+    free (info_color);
+
     return irc_color_term2irc[number];
 }
 
@@ -441,20 +447,28 @@ irc_color_convert_rgb2irc (int rgb)
 int
 irc_color_convert_term2irc (int color)
 {
-    char str_color[64], *error;
-    const char *info_color;
+    char str_color[64], *error, *info_color;
     long number;
 
     snprintf (str_color, sizeof (str_color), "%d", color);
 
     info_color = weechat_info_get ("color_term2rgb", str_color);
     if (!info_color || !info_color[0])
+    {
+        if (info_color)
+            free (info_color);
         return -1;
+    }
 
     error = NULL;
     number = strtol (info_color, &error, 10);
     if (!error || error[0] || (number < 0) || (number > 0xFFFFFF))
+    {
+        free (info_color);
         return -1;
+    }
+
+    free (info_color);
 
     return irc_color_convert_rgb2irc (number);
 }
@@ -740,6 +754,7 @@ char *
 irc_color_decode_ansi (const char *string, int keep_colors)
 {
     struct t_irc_color_ansi_state ansi_state;
+    char *ansi_regex;
 
     /* allocate/compile regex if needed (first call) */
     if (!irc_color_regex_ansi)
@@ -747,14 +762,19 @@ irc_color_decode_ansi (const char *string, int keep_colors)
         irc_color_regex_ansi = malloc (sizeof (*irc_color_regex_ansi));
         if (!irc_color_regex_ansi)
             return NULL;
+        ansi_regex = weechat_info_get ("color_ansi_regex", NULL);
         if (weechat_string_regcomp (irc_color_regex_ansi,
-                                    weechat_info_get ("color_ansi_regex", NULL),
+                                    ansi_regex,
                                     REG_EXTENDED) != 0)
         {
+            if (ansi_regex)
+                free (ansi_regex);
             free (irc_color_regex_ansi);
             irc_color_regex_ansi = NULL;
             return NULL;
         }
+        if (ansi_regex)
+            free (ansi_regex);
     }
 
     ansi_state.keep_colors = keep_colors;
diff --git a/src/plugins/irc/irc-config.c b/src/plugins/irc/irc-config.c
index 4cf44d175..f133eb37f 100644
--- a/src/plugins/irc/irc-config.c
+++ b/src/plugins/irc/irc-config.c
@@ -213,7 +213,7 @@ irc_config_compute_nick_colors ()
                 {
                     if (ptr_nick->color)
                         free (ptr_nick->color);
-                    ptr_nick->color = strdup (irc_nick_find_color (ptr_nick->name));
+                    ptr_nick->color = irc_nick_find_color (ptr_nick->name);
                 }
             }
             if (ptr_channel->pv_remote_nick_color)
diff --git a/src/plugins/irc/irc-ctcp.c b/src/plugins/irc/irc-ctcp.c
index 306348ea4..aaacecd24 100644
--- a/src/plugins/irc/irc-ctcp.c
+++ b/src/plugins/irc/irc-ctcp.c
@@ -328,8 +328,7 @@ irc_ctcp_reply_to_nick (struct t_irc_server *server,
 char *
 irc_ctcp_replace_variables (struct t_irc_server *server, const char *format)
 {
-    char *res, *temp, *username, *realname;
-    const char *info;
+    char *res, *temp, *username, *realname, *info, *info2;
     time_t now;
     struct tm *local_time;
     char buf[4096];
@@ -354,6 +353,8 @@ irc_ctcp_replace_variables (struct t_irc_server *server, const char *format)
     info = weechat_info_get ("version_git", "");
     temp = weechat_string_replace (res, "$git", info);
     free (res);
+    if (info)
+        free (info);
     if (!temp)
         return NULL;
     res = temp;
@@ -365,13 +366,18 @@ irc_ctcp_replace_variables (struct t_irc_server *server, const char *format)
      *   0.4.0-dev (git: v0.3.9-104-g7eb5cc4)
      */
     info = weechat_info_get ("version_git", "");
+    info2 = weechat_info_get ("version", "");
     snprintf (buf, sizeof (buf), "%s%s%s%s",
-              weechat_info_get ("version", ""),
+              info2,
               (info && info[0]) ? " (git: " : "",
               (info && info[0]) ? info : "",
               (info && info[0]) ? ")" : "");
     temp = weechat_string_replace (res, "$versiongit", buf);
     free (res);
+    if (info)
+        free (info);
+    if (info2)
+        free (info2);
     if (!temp)
         return NULL;
     res = temp;
@@ -384,6 +390,8 @@ irc_ctcp_replace_variables (struct t_irc_server *server, const char *format)
     info = weechat_info_get ("version", "");
     temp = weechat_string_replace (res, "$version", info);
     free (res);
+    if (info)
+        free (info);
     if (!temp)
         return NULL;
     res = temp;
@@ -395,6 +403,8 @@ irc_ctcp_replace_variables (struct t_irc_server *server, const char *format)
     info = weechat_info_get ("date", "");
     temp = weechat_string_replace (res, "$compilation", info);
     free (res);
+    if (info)
+        free (info);
     if (!temp)
         return NULL;
     res = temp;
@@ -430,6 +440,8 @@ irc_ctcp_replace_variables (struct t_irc_server *server, const char *format)
     info = weechat_info_get ("weechat_site", "");
     temp = weechat_string_replace (res, "$site", info);
     free (res);
+    if (info)
+        free (info);
     if (!temp)
         return NULL;
     res = temp;
@@ -441,6 +453,8 @@ irc_ctcp_replace_variables (struct t_irc_server *server, const char *format)
     info = weechat_info_get ("weechat_site_download", "");
     temp = weechat_string_replace (res, "$download", info);
     free (res);
+    if (info)
+        free (info);
     if (!temp)
         return NULL;
     res = temp;
@@ -974,7 +988,7 @@ irc_ctcp_recv (struct t_irc_server *server, time_t date, const char *command,
                const char *nick, const char *remote_nick, char *arguments,
                char *message)
 {
-    char *pos_end, *pos_space, *pos_args;
+    char *pos_end, *pos_space, *pos_args, *nick_color;
     const char *reply;
     char *decoded_reply;
     struct t_irc_channel *ptr_channel;
@@ -1014,6 +1028,12 @@ irc_ctcp_recv (struct t_irc_server *server, time_t date, const char *command,
                 irc_channel_nick_speaking_time_remove_old (channel);
                 irc_channel_nick_speaking_time_add (server, channel, nick,
                                                     time (NULL));
+                if (ptr_nick)
+                    nick_color = strdup (ptr_nick->color);
+                else if (nick)
+                    nick_color = irc_nick_find_color (nick);
+                else
+                    nick_color = strdup (IRC_COLOR_CHAT_NICK);
                 weechat_printf_date_tags (
                     channel->buffer,
                     date,
@@ -1026,11 +1046,13 @@ irc_ctcp_recv (struct t_irc_server *server, time_t date, const char *command,
                     "%s%s%s%s%s%s%s",
                     weechat_prefix ("action"),
                     irc_nick_mode_for_display (server, ptr_nick, 0),
-                    (ptr_nick) ? ptr_nick->color : ((nick) ? irc_nick_find_color (nick) : IRC_COLOR_CHAT_NICK),
+                    nick_color,
                     nick,
                     (pos_args) ? IRC_COLOR_RESET : "",
                     (pos_args) ? " " : "",
                     (pos_args) ? pos_args : "");
+                if (nick_color)
+                    free (nick_color);
             }
             else
             {
diff --git a/src/plugins/irc/irc-info.c b/src/plugins/irc/irc-info.c
index b284e9148..5c5b0d05d 100644
--- a/src/plugins/irc/irc-info.c
+++ b/src/plugins/irc/irc-info.c
@@ -64,14 +64,13 @@ irc_info_create_string_with_pointer (char **string, void *pointer)
  * Returns IRC info "irc_is_channel".
  */
 
-const char *
+char *
 irc_info_info_irc_is_channel_cb (const void *pointer, void *data,
                                  const char *info_name,
                                  const char *arguments)
 {
     char *pos_comma, *server;
     const char *pos_channel;
-    static char str_true[2] = "1";
     struct t_irc_server *ptr_server;
 
     /* make C compiler happy */
@@ -92,37 +91,36 @@ irc_info_info_irc_is_channel_cb (const void *pointer, void *data,
             free (server);
         }
     }
-    if (irc_channel_is_channel (ptr_server, pos_channel))
-        return str_true;
-    return NULL;
+
+    return (irc_channel_is_channel (ptr_server, pos_channel)) ?
+        strdup ("1") : NULL;
 }
 
 /*
  * Returns IRC info "irc_is_nick".
  */
 
-const char *
+char *
 irc_info_info_irc_is_nick_cb (const void *pointer, void *data,
                               const char *info_name,
                               const char *arguments)
 {
-    static char str_true[2] = "1";
-
     /* make C compiler happy */
     (void) pointer;
     (void) data;
     (void) info_name;
 
-    if (arguments && arguments[0] && irc_nick_is_nick (arguments))
-        return str_true;
-    return NULL;
+    if (!arguments || !arguments[0])
+        return NULL;
+
+    return (irc_nick_is_nick (arguments)) ? strdup ("1") : NULL;
 }
 
 /*
  * Returns IRC info "irc_nick".
  */
 
-const char *
+char *
 irc_info_info_irc_nick_cb (const void *pointer, void *data,
                            const char *info_name,
                            const char *arguments)
@@ -138,35 +136,40 @@ irc_info_info_irc_nick_cb (const void *pointer, void *data,
         return NULL;
 
     ptr_server = irc_server_search (arguments);
-    if (ptr_server)
-        return ptr_server->nick;
 
-    return NULL;
+    return (ptr_server && ptr_server->nick) ?
+        strdup (ptr_server->nick) : NULL;
 }
 
 /*
  * Returns IRC info "irc_nick_from_host".
  */
 
-const char *
+char *
 irc_info_info_irc_nick_from_host_cb (const void *pointer, void *data,
                                      const char *info_name,
                                      const char *arguments)
 {
+    const char *ptr_host;
+
     /* make C compiler happy */
     (void) pointer;
     (void) data;
     (void) info_name;
 
-    return (arguments && arguments[0]) ?
-        irc_message_get_nick_from_host (arguments) : NULL;
+    if (!arguments || !arguments[0])
+        return NULL;
+
+    ptr_host = irc_message_get_nick_from_host (arguments);
+
+    return (ptr_host) ? strdup (ptr_host) : NULL;
 }
 
 /*
  * Returns IRC info "irc_nick_color".
  */
 
-const char *
+char *
 irc_info_info_irc_nick_color_cb (const void *pointer, void *data,
                                  const char *info_name,
                                  const char *arguments)
@@ -176,15 +179,17 @@ irc_info_info_irc_nick_color_cb (const void *pointer, void *data,
     (void) data;
     (void) info_name;
 
-    return (arguments && arguments[0]) ?
-        irc_nick_find_color (arguments) : NULL;
+    if (!arguments || !arguments[0])
+        return NULL;
+
+    return irc_nick_find_color (arguments);
 }
 
 /*
  * Returns IRC info "irc_nick_color_name".
  */
 
-const char *
+char *
 irc_info_info_irc_nick_color_name_cb (const void *pointer, void *data,
                                       const char *info_name,
                                       const char *arguments)
@@ -194,15 +199,17 @@ irc_info_info_irc_nick_color_name_cb (const void *pointer, void *data,
     (void) data;
     (void) info_name;
 
-    return (arguments && arguments[0]) ?
-        irc_nick_find_color_name (arguments) : NULL;
+    if (!arguments || !arguments[0])
+        return NULL;
+
+    return irc_nick_find_color_name (arguments);
 }
 
 /*
  * Returns IRC info "irc_buffer".
  */
 
-const char *
+char *
 irc_info_info_irc_buffer_cb (const void *pointer, void *data,
                              const char *info_name,
                              const char *arguments)
@@ -281,14 +288,18 @@ irc_info_info_irc_buffer_cb (const void *pointer, void *data,
     {
         irc_info_create_string_with_pointer (&ptr_channel->buffer_as_string,
                                              ptr_channel->buffer);
-        return ptr_channel->buffer_as_string;
+        return (ptr_channel->buffer_as_string) ?
+            strdup (ptr_channel->buffer_as_string) : NULL;
     }
+
     if (ptr_server)
     {
         irc_info_create_string_with_pointer (&ptr_server->buffer_as_string,
                                              ptr_server->buffer);
-        return ptr_server->buffer_as_string;
+        return (ptr_server->buffer_as_string) ?
+            strdup (ptr_server->buffer_as_string) : NULL;
     }
+
     return NULL;
 }
 
@@ -296,14 +307,13 @@ irc_info_info_irc_buffer_cb (const void *pointer, void *data,
  * Returns IRC info "irc_server_isupport".
  */
 
-const char *
+char *
 irc_info_info_irc_server_isupport_cb (const void *pointer, void *data,
                                       const char *info_name,
                                       const char *arguments)
 {
     char *pos_comma, *server;
     const char *isupport_value;
-    static char str_true[2] = "1";
     struct t_irc_server *ptr_server;
 
     /* make C compiler happy */
@@ -326,14 +336,15 @@ irc_info_info_irc_server_isupport_cb (const void *pointer, void *data,
             }
         }
     }
-    return (isupport_value) ? str_true : NULL;
+
+    return (isupport_value) ? strdup ("1") : NULL;
 }
 
 /*
  * Returns IRC info "irc_server_isupport_value".
  */
 
-const char *
+char *
 irc_info_info_irc_server_isupport_value_cb (const void *pointer, void *data,
                                             const char *info_name,
                                             const char *arguments)
@@ -362,7 +373,8 @@ irc_info_info_irc_server_isupport_value_cb (const void *pointer, void *data,
             }
         }
     }
-    return isupport_value;
+
+    return (isupport_value) ? strdup (isupport_value) : NULL;
 }
 
 /*
diff --git a/src/plugins/irc/irc-nick.c b/src/plugins/irc/irc-nick.c
index efecd8e89..95357dfad 100644
--- a/src/plugins/irc/irc-nick.c
+++ b/src/plugins/irc/irc-nick.c
@@ -98,7 +98,7 @@ irc_nick_is_nick (const char *string)
  * Returns a WeeChat color code (that can be used for display).
  */
 
-const char *
+char *
 irc_nick_find_color (const char *nickname)
 {
     return weechat_info_get ("nick_color", nickname);
@@ -110,7 +110,7 @@ irc_nick_find_color (const char *nickname)
  * Returns the name of a color (for example: "green").
  */
 
-const char *
+char *
 irc_nick_find_color_name (const char *nickname)
 {
     return weechat_info_get ("nick_color_name", nickname);
@@ -309,7 +309,7 @@ irc_nick_get_prefix_color_name (struct t_irc_server *server, char prefix)
  * Gets nick color for nicklist.
  */
 
-const char *
+char *
 irc_nick_get_color_for_nicklist (struct t_irc_server *server,
                                  struct t_irc_nick *nick)
 {
@@ -318,17 +318,17 @@ irc_nick_get_color_for_nicklist (struct t_irc_server *server,
     static char *nick_color_away = "weechat.color.nicklist_away";
 
     if (nick->away)
-        return nick_color_away;
+        return strdup (nick_color_away);
 
     if (weechat_config_boolean (irc_config_look_color_nicks_in_nicklist))
     {
         if (irc_server_strcasecmp (server, nick->name, server->nick) == 0)
-            return nick_color_self;
+            return strdup (nick_color_self);
         else
             return irc_nick_find_color_name (nick->name);
     }
 
-    return nick_color_bar_fg;
+    return strdup (nick_color_bar_fg);
 }
 
 /*
@@ -341,14 +341,18 @@ irc_nick_nicklist_add (struct t_irc_server *server,
                        struct t_irc_nick *nick)
 {
     struct t_gui_nick_group *ptr_group;
+    char *color;
 
     ptr_group = irc_nick_get_nicklist_group (server, channel->buffer, nick);
+    color = irc_nick_get_color_for_nicklist (server, nick);
     weechat_nicklist_add_nick (channel->buffer, ptr_group,
                                nick->name,
-                               irc_nick_get_color_for_nicklist (server, nick),
+                               color,
                                nick->prefix,
                                irc_nick_get_prefix_color_name (server, nick->prefix[0]),
                                1);
+    if (color)
+        free (color);
 }
 
 /*
@@ -425,6 +429,7 @@ irc_nick_nicklist_set_color_all ()
     struct t_irc_server *ptr_server;
     struct t_irc_channel *ptr_channel;
     struct t_irc_nick *ptr_nick;
+    char *color;
 
     for (ptr_server = irc_servers; ptr_server;
          ptr_server = ptr_server->next_server)
@@ -435,9 +440,10 @@ irc_nick_nicklist_set_color_all ()
             for (ptr_nick = ptr_channel->nicks; ptr_nick;
                  ptr_nick = ptr_nick->next_nick)
             {
-                irc_nick_nicklist_set (ptr_channel, ptr_nick, "color",
-                                       irc_nick_get_color_for_nicklist (ptr_server,
-                                                                        ptr_nick));
+                color = irc_nick_get_color_for_nicklist (ptr_server, ptr_nick);
+                irc_nick_nicklist_set (ptr_channel, ptr_nick, "color", color);
+                if (color)
+                    free (color);
             }
         }
     }
@@ -517,7 +523,7 @@ irc_nick_new (struct t_irc_server *server, struct t_irc_channel *channel,
     if (irc_server_strcasecmp (server, new_nick->name, server->nick) == 0)
         new_nick->color = strdup (IRC_COLOR_CHAT_NICK_SELF);
     else
-        new_nick->color = strdup (irc_nick_find_color (new_nick->name));
+        new_nick->color = irc_nick_find_color (new_nick->name);
 
     /* add nick to end of list */
     new_nick->prev_nick = channel->last_nick;
@@ -566,7 +572,7 @@ irc_nick_change (struct t_irc_server *server, struct t_irc_channel *channel,
     if (nick_is_me)
         nick->color = strdup (IRC_COLOR_CHAT_NICK_SELF);
     else
-        nick->color = strdup (irc_nick_find_color (nick->name));
+        nick->color = irc_nick_find_color (nick->name);
 
     /* add nick in nicklist */
     irc_nick_nicklist_add (server, channel, nick);
@@ -749,11 +755,15 @@ void
 irc_nick_set_away (struct t_irc_server *server, struct t_irc_channel *channel,
                    struct t_irc_nick *nick, int is_away)
 {
+    char *color;
+
     if (is_away != nick->away)
     {
         nick->away = is_away;
-        irc_nick_nicklist_set (channel, nick, "color",
-                               irc_nick_get_color_for_nicklist (server, nick));
+        color = irc_nick_get_color_for_nicklist (server, nick);
+        irc_nick_nicklist_set (channel, nick, "color", color);
+        if (color)
+            free (color);
     }
 }
 
@@ -820,12 +830,25 @@ irc_nick_as_prefix (struct t_irc_server *server, struct t_irc_nick *nick,
                     const char *nickname, const char *force_color)
 {
     static char result[256];
+    char *color;
+
+    if (force_color)
+        color = strdup (force_color);
+    else if (nick)
+        color = strdup (nick->color);
+    else if (nickname)
+        color = irc_nick_find_color (nickname);
+    else
+        color = strdup (IRC_COLOR_CHAT_NICK);
 
     snprintf (result, sizeof (result), "%s%s%s\t",
               irc_nick_mode_for_display (server, nick, 1),
-              (force_color) ? force_color : ((nick) ? nick->color : ((nickname) ? irc_nick_find_color (nickname) : IRC_COLOR_CHAT_NICK)),
+              color,
               (nick) ? nick->name : nickname);
 
+    if (color)
+        free (color);
+
     return result;
 }
 
@@ -837,6 +860,10 @@ const char *
 irc_nick_color_for_msg (struct t_irc_server *server, int server_message,
                         struct t_irc_nick *nick, const char *nickname)
 {
+    static char color[16][64];
+    static int index_color = 0;
+    char *color_found;
+
     if (server_message
         && !weechat_config_boolean (irc_config_look_color_nicks_in_server_messages))
     {
@@ -853,7 +880,14 @@ irc_nick_color_for_msg (struct t_irc_server *server, int server_message,
         {
             return IRC_COLOR_CHAT_NICK_SELF;
         }
-        return irc_nick_find_color (nickname);
+        color_found = irc_nick_find_color (nickname);
+        index_color = (index_color + 1) % 16;
+        snprintf (color[index_color], sizeof (color[index_color]),
+                  "%s",
+                  color_found);
+        if (color_found)
+            free (color_found);
+        return color[index_color];
     }
 
     return IRC_COLOR_CHAT_NICK;
@@ -869,7 +903,7 @@ irc_nick_color_for_pv (struct t_irc_channel *channel, const char *nickname)
     if (weechat_config_boolean (irc_config_look_color_pv_nick_like_channel))
     {
         if (!channel->pv_remote_nick_color)
-            channel->pv_remote_nick_color = strdup (irc_nick_find_color (nickname));
+            channel->pv_remote_nick_color = irc_nick_find_color (nickname);
         if (channel->pv_remote_nick_color)
             return channel->pv_remote_nick_color;
     }
diff --git a/src/plugins/irc/irc-nick.h b/src/plugins/irc/irc-nick.h
index 7f6cc8e20..fb00bd906 100644
--- a/src/plugins/irc/irc-nick.h
+++ b/src/plugins/irc/irc-nick.h
@@ -48,8 +48,8 @@ struct t_irc_nick
 extern int irc_nick_valid (struct t_irc_channel *channel,
                            struct t_irc_nick *nick);
 extern int irc_nick_is_nick (const char *string);
-extern const char *irc_nick_find_color (const char *nickname);
-extern const char *irc_nick_find_color_name (const char *nickname);
+extern char *irc_nick_find_color (const char *nickname);
+extern char *irc_nick_find_color_name (const char *nickname);
 extern int irc_nick_is_op (struct t_irc_server *server,
                            struct t_irc_nick *nick);
 extern int irc_nick_has_prefix_mode (struct t_irc_server *server,
diff --git a/src/plugins/irc/irc-protocol.c b/src/plugins/irc/irc-protocol.c
index f82edc339..777141e2c 100644
--- a/src/plugins/irc/irc-protocol.c
+++ b/src/plugins/irc/irc-protocol.c
@@ -2169,6 +2169,7 @@ IRC_PROTOCOL_CALLBACK(pong)
 IRC_PROTOCOL_CALLBACK(privmsg)
 {
     char *pos_args, *pos_target, str_tags[1024], *str_color, status_msg[2];
+    char *color;
     const char *remote_nick, *pv_tags;
     int is_channel, nick_is_me;
     struct t_irc_channel *ptr_channel;
@@ -2246,8 +2247,10 @@ IRC_PROTOCOL_CALLBACK(privmsg)
             else
             {
                 /* standard message (to "#channel") */
-                str_color = irc_color_for_tags (
-                    irc_nick_find_color_name ((ptr_nick) ? ptr_nick->name : nick));
+                color = irc_nick_find_color_name ((ptr_nick) ? ptr_nick->name : nick);
+                str_color = irc_color_for_tags (color);
+                if (color)
+                    free (color);
                 snprintf (str_tags, sizeof (str_tags),
                           "notify_message,prefix_nick_%s",
                           (str_color) ? str_color : "default");
@@ -2318,8 +2321,10 @@ IRC_PROTOCOL_CALLBACK(privmsg)
         {
             if (weechat_config_boolean (irc_config_look_color_pv_nick_like_channel))
             {
-                str_color = irc_color_for_tags (
-                    irc_nick_find_color_name (nick));
+                color = irc_nick_find_color_name (nick);
+                str_color = irc_color_for_tags (color);
+                if (color)
+                    free (color);
             }
             else
             {
@@ -4667,7 +4672,7 @@ IRC_PROTOCOL_CALLBACK(352)
 IRC_PROTOCOL_CALLBACK(353)
 {
     char *pos_channel, *pos_nick, *pos_nick_orig, *pos_host, *nickname;
-    char *prefixes, *str_nicks;
+    char *prefixes, *str_nicks, *color;
     int args, i, length;
     struct t_irc_channel *ptr_channel;
 
@@ -4764,7 +4769,12 @@ IRC_PROTOCOL_CALLBACK(353)
                     if (irc_server_strcasecmp (server, nickname, server->nick) == 0)
                         strcat (str_nicks, IRC_COLOR_CHAT_NICK_SELF);
                     else
-                        strcat (str_nicks, irc_nick_find_color (nickname));
+                    {
+                        color = irc_nick_find_color (nickname);
+                        strcat (str_nicks, color);
+                        if (color)
+                            free (color);
+                    }
                 }
                 else
                     strcat (str_nicks, IRC_COLOR_RESET);
@@ -4956,7 +4966,7 @@ IRC_PROTOCOL_CALLBACK(366)
     struct t_infolist *infolist;
     struct t_config_option *ptr_option;
     int num_nicks, num_op, num_halfop, num_voice, num_normal, length, i;
-    char *string, str_nicks_count[2048];
+    char *string, str_nicks_count[2048], *color;
     const char *prefix, *prefix_color, *nickname;
 
     IRC_PROTOCOL_MIN_ARGS(5);
@@ -5029,7 +5039,12 @@ IRC_PROTOCOL_CALLBACK(366)
                                     if (irc_server_strcasecmp (server, nickname, server->nick) == 0)
                                         strcat (string, IRC_COLOR_CHAT_NICK_SELF);
                                     else
-                                        strcat (string, irc_nick_find_color (nickname));
+                                    {
+                                        color = irc_nick_find_color (nickname);
+                                        strcat (string, color);
+                                        if (color)
+                                            free (color);
+                                    }
                                 }
                                 else
                                     strcat (string, IRC_COLOR_RESET);
diff --git a/src/plugins/irc/irc-sasl.c b/src/plugins/irc/irc-sasl.c
index 7cfc1ed29..f3074480d 100644
--- a/src/plugins/irc/irc-sasl.c
+++ b/src/plugins/irc/irc-sasl.c
@@ -96,8 +96,7 @@ irc_sasl_mechanism_plain (const char *sasl_username, const char *sasl_password)
 char *
 irc_sasl_get_key_content (struct t_irc_server *server, const char *sasl_key)
 {
-    const char *weechat_dir;
-    char *key_path1, *key_path2, *content;
+    char *weechat_dir, *key_path1, *key_path2, *content;
 
     if (!sasl_key)
         return NULL;
@@ -122,6 +121,8 @@ irc_sasl_get_key_content (struct t_irc_server *server, const char *sasl_key)
             (key_path2) ? key_path2 : ((key_path1) ? key_path1 : sasl_key));
     }
 
+    if (weechat_dir)
+        free (weechat_dir);
     if (key_path1)
         free (key_path1);
     if (key_path2)
diff --git a/src/plugins/irc/irc-server.c b/src/plugins/irc/irc-server.c
index 36dd6889e..dfa74d88f 100644
--- a/src/plugins/irc/irc-server.c
+++ b/src/plugins/irc/irc-server.c
@@ -1228,9 +1228,9 @@ irc_server_get_default_msg (const char *default_msg,
                             struct t_irc_server *server,
                             const char *channel_name)
 {
-    const char *version;
+    char *version;
     struct t_hashtable *extra_vars;
-    char *msg;
+    char *msg, *res;
 
     /*
      * "%v" for version is deprecated since WeeChat 1.6, where
@@ -1240,8 +1240,11 @@ irc_server_get_default_msg (const char *default_msg,
     if (strstr (default_msg, "%v") && !strstr (default_msg, "${"))
     {
         version = weechat_info_get ("version", "");
-        return weechat_string_replace (default_msg, "%v",
-                                       (version) ? version : "");
+        res = weechat_string_replace (default_msg, "%v",
+                                      (version) ? version : "");
+        if (version)
+            free (version);
+        return res;
     }
 
     extra_vars = weechat_hashtable_new (32,
@@ -4344,7 +4347,8 @@ irc_server_gnutls_callback (const void *pointer, void *data,
     unsigned int i, cert_list_len, status;
     time_t cert_time;
     char *cert_path0, *cert_path1, *cert_path2, *cert_str, *fingerprint_eval;
-    const char *weechat_dir, *ptr_fingerprint;
+    char *weechat_dir;
+    const char *ptr_fingerprint;
     int rc, ret, fingerprint_match, hostname_match, cert_temp_init;
 #if LIBGNUTLS_VERSION_NUMBER >= 0x010706 /* 1.7.6 */
     gnutls_datum_t cinfo;
@@ -4368,6 +4372,7 @@ irc_server_gnutls_callback (const void *pointer, void *data,
     cert_list = NULL;
     cert_list_len = 0;
     fingerprint_eval = NULL;
+    weechat_dir = NULL;
 
     if (action == WEECHAT_HOOK_CONNECT_GNUTLS_CB_VERIFY_CERT)
     {
@@ -4702,7 +4707,8 @@ end:
 
     if (cert_temp_init)
         gnutls_x509_crt_deinit (cert_temp);
-
+    if (weechat_dir)
+        free (weechat_dir);
     if (fingerprint_eval)
         free (fingerprint_eval);
 
diff --git a/src/plugins/javascript/weechat-js-api.cpp b/src/plugins/javascript/weechat-js-api.cpp
index 7dd8272d4..8649897be 100644
--- a/src/plugins/javascript/weechat-js-api.cpp
+++ b/src/plugins/javascript/weechat-js-api.cpp
@@ -95,8 +95,6 @@ extern "C"
     plugin_script_str2ptr (weechat_js_plugin,                           \
                            JS_CURRENT_SCRIPT_NAME,                      \
                            js_function_name.c_str(), __string)
-#define API_STATIC_STRING(__string)                                     \
-    plugin_script_get_static_string(&js_data, __string);
 #define API_RETURN_OK return v8::True();
 #define API_RETURN_ERROR return v8::False();
 #define API_RETURN_EMPTY                                                \
@@ -2847,14 +2845,14 @@ API_FUNC(hook_modifier_exec)
     API_RETURN_STRING_FREE(result);
 }
 
-const char *
+char *
 weechat_js_api_hook_info_cb (const void *pointer, void *data,
                              const char *info_name,
                              const char *arguments)
 {
     struct t_plugin_script *script;
     void *func_argv[3];
-    char empty_arg[1] = { '\0' }, *result;
+    char empty_arg[1] = { '\0' };
     const char *ptr_function, *ptr_data;
 
     script = (struct t_plugin_script *)pointer;
@@ -2866,12 +2864,10 @@ weechat_js_api_hook_info_cb (const void *pointer, void *data,
         func_argv[1] = (info_name) ? (char *)info_name : empty_arg;
         func_argv[2] = (arguments) ? (char *)arguments : empty_arg;
 
-        result = (char *)weechat_js_exec (script,
-                                          WEECHAT_SCRIPT_EXEC_STRING,
-                                          ptr_function,
-                                          "sss", func_argv);
-
-        return API_STATIC_STRING(result);
+        return (char *)weechat_js_exec (script,
+                                        WEECHAT_SCRIPT_EXEC_STRING,
+                                        ptr_function,
+                                        "sss", func_argv);
     }
 
     return NULL;
@@ -4014,7 +4010,7 @@ API_FUNC(info_get)
 
     result = weechat_info_get (*info_name, *arguments);
 
-    API_RETURN_STRING(result);
+    API_RETURN_STRING_FREE(result);
 }
 
 API_FUNC(info_get_hashtable)
diff --git a/src/plugins/javascript/weechat-js.cpp b/src/plugins/javascript/weechat-js.cpp
index 1c9d4a98b..996444ffe 100644
--- a/src/plugins/javascript/weechat-js.cpp
+++ b/src/plugins/javascript/weechat-js.cpp
@@ -56,7 +56,6 @@ int js_eval_mode = 0;
 int js_eval_send_input = 0;
 int js_eval_exec_commands = 0;
 struct t_gui_buffer *js_eval_buffer = NULL;
-char *js_eval_output = NULL;
 
 struct t_plugin_script *js_scripts = NULL;
 struct t_plugin_script *last_js_script = NULL;
@@ -756,12 +755,12 @@ weechat_js_hdata_cb (const void *pointer, void *data,
  * Returns javascript info "javascript_eval".
  */
 
-const char *
+char *
 weechat_js_info_eval_cb (const void *pointer, void *data,
                          const char *info_name,
                          const char *arguments)
 {
-    static const char *not_implemented = "not yet implemented";
+    const char *not_implemented = "not yet implemented";
 
     /* make C compiler happy */
     (void) pointer;
@@ -769,7 +768,7 @@ weechat_js_info_eval_cb (const void *pointer, void *data,
     (void) info_name;
     (void) arguments;
 
-    return not_implemented;
+    return strdup (not_implemented);
 }
 
 /*
@@ -977,8 +976,6 @@ weechat_plugin_end (struct t_weechat_plugin *plugin)
     if (js_action_autoload_list)
         free (js_action_autoload_list);
     /* weechat_string_dyn_free (js_buffer_output, 1); */
-    if (js_eval_output)
-        free (js_eval_output);
 
     return WEECHAT_RC_OK;
 }
diff --git a/src/plugins/logger/logger.c b/src/plugins/logger/logger.c
index 4711c2cb4..e001ec70e 100644
--- a/src/plugins/logger/logger.c
+++ b/src/plugins/logger/logger.c
@@ -297,8 +297,7 @@ logger_get_mask_for_buffer (struct t_gui_buffer *buffer)
 char *
 logger_get_mask_expanded (struct t_gui_buffer *buffer, const char *mask)
 {
-    char *mask2, *mask3, *mask4, *mask5, *mask6, *mask7;
-    const char *dir_separator;
+    char *mask2, *mask3, *mask4, *mask5, *mask6, *mask7, *dir_separator;
     int length;
     time_t seconds;
     struct tm *date_tmp;
@@ -374,6 +373,7 @@ logger_get_mask_expanded (struct t_gui_buffer *buffer, const char *mask)
     }
 
 end:
+    free (dir_separator);
     if (mask2)
         free (mask2);
     if (mask3)
@@ -397,9 +397,8 @@ end:
 char *
 logger_get_filename (struct t_gui_buffer *buffer)
 {
-    char *res, *mask_expanded, *file_path;
+    char *res, *mask_expanded, *file_path, *dir_separator, *weechat_dir;
     const char *mask;
-    const char *dir_separator, *weechat_dir;
     int length;
 
     res = NULL;
@@ -411,7 +410,10 @@ logger_get_filename (struct t_gui_buffer *buffer)
         return NULL;
     weechat_dir = weechat_info_get ("weechat_dir", "");
     if (!weechat_dir)
+    {
+        free (dir_separator);
         return NULL;
+    }
 
     /* get filename mask for buffer */
     mask = logger_get_mask_for_buffer (buffer);
@@ -423,6 +425,8 @@ logger_get_filename (struct t_gui_buffer *buffer)
               "\"%s\", logging is disabled for this buffer"),
             weechat_prefix ("error"), LOGGER_PLUGIN_NAME,
             weechat_buffer_get_string (buffer, "name"));
+        free (dir_separator);
+        free (weechat_dir);
         return NULL;
     }
 
@@ -447,6 +451,8 @@ logger_get_filename (struct t_gui_buffer *buffer)
     }
 
 end:
+    free (dir_separator);
+    free (weechat_dir);
     if (mask_expanded)
         free (mask_expanded);
     if (file_path)
@@ -463,7 +469,7 @@ void
 logger_set_log_filename (struct t_logger_buffer *logger_buffer)
 {
     char *log_filename, *pos_last_sep;
-    const char *dir_separator;
+    char *dir_separator;
     struct t_logger_buffer *ptr_logger_buffer;
 
     /* get log filename for buffer */
@@ -505,6 +511,7 @@ logger_set_log_filename (struct t_logger_buffer *logger_buffer)
             weechat_mkdir_parents (log_filename, 0700);
             pos_last_sep[0] = dir_separator[0];
         }
+        free (dir_separator);
     }
 
     /* set log filename */
@@ -519,14 +526,11 @@ void
 logger_write_line (struct t_logger_buffer *logger_buffer,
                    const char *format, ...)
 {
-    char *message, buf_time[256], buf_beginning[1024];
-    const char *charset;
+    char *message, buf_time[256], buf_beginning[1024], *charset;
     time_t seconds;
     struct tm *date_tmp;
     int log_level;
 
-    charset = weechat_info_get ("charset_terminal", "");
-
     if (!logger_buffer->log_file)
     {
         log_level = logger_get_level_for_buffer (logger_buffer->buffer);
@@ -583,10 +587,13 @@ logger_write_line (struct t_logger_buffer *logger_buffer,
             snprintf (buf_beginning, sizeof (buf_beginning),
                       _("%s\t****  Beginning of log  ****"),
                       buf_time);
+            charset = weechat_info_get ("charset_terminal", "");
             message = (charset) ?
                 weechat_iconv_from_internal (charset, buf_beginning) : NULL;
             fprintf (logger_buffer->log_file,
                      "%s\n", (message) ? message : buf_beginning);
+            if (charset)
+                free (charset);
             if (message)
                 free (message);
             logger_buffer->flush_needed = 1;
@@ -597,10 +604,13 @@ logger_write_line (struct t_logger_buffer *logger_buffer,
     weechat_va_format (format);
     if (vbuffer)
     {
+        charset = weechat_info_get ("charset_terminal", "");
         message = (charset) ?
             weechat_iconv_from_internal (charset, vbuffer) : NULL;
         fprintf (logger_buffer->log_file,
                  "%s\n", (message) ? message : vbuffer);
+        if (charset)
+            free (charset);
         if (message)
             free (message);
         logger_buffer->flush_needed = 1;
@@ -893,15 +903,12 @@ logger_backlog_check_conditions (struct t_gui_buffer *buffer)
 void
 logger_backlog (struct t_gui_buffer *buffer, const char *filename, int lines)
 {
-    const char *charset;
     struct t_logger_line *last_lines, *ptr_lines;
-    char *pos_message, *pos_tab, *error, *message;
+    char *charset, *pos_message, *pos_tab, *error, *message;
     time_t datetime, time_now;
     struct tm tm_line;
     int num_lines;
 
-    charset = weechat_info_get ("charset_terminal", "");
-
     weechat_buffer_set (buffer, "print_hooks_enabled", "0");
 
     num_lines = 0;
@@ -932,8 +939,11 @@ logger_backlog (struct t_gui_buffer *buffer, const char *filename, int lines)
         }
         pos_message = (pos_message && (datetime != 0)) ?
             pos_message + 1 : ptr_lines->data;
+        charset = weechat_info_get ("charset_terminal", "");
         message = (charset) ?
             weechat_iconv_to_internal (charset, pos_message) : strdup (pos_message);
+        if (charset)
+            free (charset);
         if (message)
         {
             pos_tab = strchr (message, '\t');
diff --git a/src/plugins/lua/weechat-lua-api.c b/src/plugins/lua/weechat-lua-api.c
index 908097a4c..10c1663d2 100644
--- a/src/plugins/lua/weechat-lua-api.c
+++ b/src/plugins/lua/weechat-lua-api.c
@@ -67,8 +67,6 @@
     plugin_script_str2ptr (weechat_lua_plugin,                          \
                            LUA_CURRENT_SCRIPT_NAME,                     \
                            lua_function_name, __string)
-#define API_STATIC_STRING(__string)                                     \
-    plugin_script_get_static_string(&lua_data, __string);
 #define API_RETURN_OK                                                   \
     {                                                                   \
         lua_pushinteger (L, 1);                                         \
@@ -3082,14 +3080,14 @@ API_FUNC(hook_modifier_exec)
     API_RETURN_STRING_FREE(result);
 }
 
-const char *
+char *
 weechat_lua_api_hook_info_cb (const void *pointer, void *data,
                               const char *info_name,
                               const char *arguments)
 {
     struct t_plugin_script *script;
     void *func_argv[3];
-    char empty_arg[1] = { '\0' }, *result;
+    char empty_arg[1] = { '\0' };
     const char *ptr_function, *ptr_data;
 
     script = (struct t_plugin_script *)pointer;
@@ -3101,12 +3099,10 @@ weechat_lua_api_hook_info_cb (const void *pointer, void *data,
         func_argv[1] = (info_name) ? (char *)info_name : empty_arg;
         func_argv[2] = (arguments) ? (char *)arguments : empty_arg;
 
-        result = (char *)weechat_lua_exec (script,
-                                           WEECHAT_SCRIPT_EXEC_STRING,
-                                           ptr_function,
-                                           "sss", func_argv);
-
-        return API_STATIC_STRING(result);
+        return (char *)weechat_lua_exec (script,
+                                         WEECHAT_SCRIPT_EXEC_STRING,
+                                         ptr_function,
+                                         "sss", func_argv);
     }
 
     return NULL;
@@ -4343,7 +4339,8 @@ API_FUNC(command_options)
 
 API_FUNC(info_get)
 {
-    const char *info_name, *arguments, *result;
+    const char *info_name, *arguments;
+    char *result;
 
     API_INIT_FUNC(1, "info_get", API_RETURN_EMPTY);
     if (lua_gettop (L) < 2)
@@ -4354,7 +4351,7 @@ API_FUNC(info_get)
 
     result = weechat_info_get (info_name, arguments);
 
-    API_RETURN_STRING(result);
+    API_RETURN_STRING_FREE(result);
 }
 
 API_FUNC(info_get_hashtable)
diff --git a/src/plugins/lua/weechat-lua.c b/src/plugins/lua/weechat-lua.c
index 47bf9f9e7..4c9880124 100644
--- a/src/plugins/lua/weechat-lua.c
+++ b/src/plugins/lua/weechat-lua.c
@@ -57,7 +57,6 @@ int lua_eval_mode = 0;
 int lua_eval_send_input = 0;
 int lua_eval_exec_commands = 0;
 struct t_gui_buffer *lua_eval_buffer = NULL;
-char *lua_eval_output = NULL;
 #if LUA_VERSION_NUM >= 502
 #define LUA_LOAD "load"
 #else
@@ -1071,23 +1070,23 @@ weechat_lua_hdata_cb (const void *pointer, void *data,
  * Returns lua info "lua_eval".
  */
 
-const char *
+char *
 weechat_lua_info_eval_cb (const void *pointer, void *data,
                           const char *info_name,
                           const char *arguments)
 {
+    char *output;
+
     /* make C compiler happy */
     (void) pointer;
     (void) data;
     (void) info_name;
 
     weechat_lua_eval (NULL, 0, 0, (arguments) ? arguments : "");
-    if (lua_eval_output)
-        free (lua_eval_output);
-    lua_eval_output = strdup (*lua_buffer_output);
+    output = strdup (*lua_buffer_output);
     weechat_string_dyn_copy (lua_buffer_output, NULL);
 
-    return lua_eval_output;
+    return output;
 }
 
 /*
@@ -1303,8 +1302,6 @@ weechat_plugin_end (struct t_weechat_plugin *plugin)
     if (lua_action_autoload_list)
         free (lua_action_autoload_list);
     weechat_string_dyn_free (lua_buffer_output, 1);
-    if (lua_eval_output)
-        free (lua_eval_output);
 
     return WEECHAT_RC_OK;
 }
diff --git a/src/plugins/perl/weechat-perl-api.c b/src/plugins/perl/weechat-perl-api.c
index 5c0ab0e0e..ab6b40608 100644
--- a/src/plugins/perl/weechat-perl-api.c
+++ b/src/plugins/perl/weechat-perl-api.c
@@ -60,8 +60,6 @@
     plugin_script_str2ptr (weechat_perl_plugin,                         \
                            PERL_CURRENT_SCRIPT_NAME,                    \
                            perl_function_name, __string)
-#define API_STATIC_STRING(__string)                                     \
-    plugin_script_get_static_string(&perl_data, __string);
 #define API_RETURN_OK XSRETURN_YES
 #define API_RETURN_ERROR XSRETURN_NO
 #define API_RETURN_EMPTY XSRETURN_EMPTY
@@ -2986,14 +2984,14 @@ API_FUNC(hook_modifier_exec)
     API_RETURN_STRING_FREE(result);
 }
 
-const char *
+char *
 weechat_perl_api_hook_info_cb (const void *pointer, void *data,
                                const char *info_name,
                                const char *arguments)
 {
     struct t_plugin_script *script;
     void *func_argv[3];
-    char empty_arg[1] = { '\0' }, *result;
+    char empty_arg[1] = { '\0' };
     const char *ptr_function, *ptr_data;
 
     script = (struct t_plugin_script *)pointer;
@@ -3005,12 +3003,10 @@ weechat_perl_api_hook_info_cb (const void *pointer, void *data,
         func_argv[1] = (info_name) ? (char *)info_name : empty_arg;
         func_argv[2] = (arguments) ? (char *)arguments : empty_arg;
 
-        result = (char *)weechat_perl_exec (script,
-                                            WEECHAT_SCRIPT_EXEC_STRING,
-                                            ptr_function,
-                                            "sss", func_argv);
-
-        return API_STATIC_STRING(result);
+        return (char *)weechat_perl_exec (script,
+                                          WEECHAT_SCRIPT_EXEC_STRING,
+                                          ptr_function,
+                                          "sss", func_argv);
     }
 
     return NULL;
@@ -4264,8 +4260,7 @@ API_FUNC(command_options)
 
 API_FUNC(info_get)
 {
-    char *info_name, *arguments;
-    const char *result;
+    char *info_name, *arguments, *result;
     dXSARGS;
 
     API_INIT_FUNC(1, "info_get", API_RETURN_EMPTY);
@@ -4277,7 +4272,7 @@ API_FUNC(info_get)
 
     result = weechat_info_get (info_name, arguments);
 
-    API_RETURN_STRING(result);
+    API_RETURN_STRING_FREE(result);
 }
 
 API_FUNC(info_get_hashtable)
diff --git a/src/plugins/perl/weechat-perl.c b/src/plugins/perl/weechat-perl.c
index 7f309d43c..8688938d9 100644
--- a/src/plugins/perl/weechat-perl.c
+++ b/src/plugins/perl/weechat-perl.c
@@ -54,7 +54,6 @@ int perl_eval_mode = 0;
 int perl_eval_send_input = 0;
 int perl_eval_exec_commands = 0;
 struct t_gui_buffer *perl_eval_buffer = NULL;
-char *perl_eval_output = NULL;
 #define PERL_EVAL_SCRIPT                                                \
     "sub script_perl_eval {\n"                                          \
     "    eval \"$_[0]\";\n"                                             \
@@ -1053,23 +1052,23 @@ weechat_perl_hdata_cb (const void *pointer, void *data,
  * Returns perl info "perl_eval".
  */
 
-const char *
+char *
 weechat_perl_info_eval_cb (const void *pointer, void *data,
                            const char *info_name,
                            const char *arguments)
 {
+    char *output;
+
     /* make C compiler happy */
     (void) pointer;
     (void) data;
     (void) info_name;
 
     weechat_perl_eval (NULL, 0, 0, (arguments) ? arguments : "");
-    if (perl_eval_output)
-        free (perl_eval_output);
-    perl_eval_output = strdup (*perl_buffer_output);
+    output = strdup (*perl_buffer_output);
     weechat_string_dyn_copy (perl_buffer_output, NULL);
 
-    return perl_eval_output;
+    return output;
 }
 
 /*
@@ -1358,8 +1357,6 @@ weechat_plugin_end (struct t_weechat_plugin *plugin)
     if (perl_action_autoload_list)
         free (perl_action_autoload_list);
     weechat_string_dyn_free (perl_buffer_output, 1);
-    if (perl_eval_output)
-        free (perl_eval_output);
 
     return WEECHAT_RC_OK;
 }
diff --git a/src/plugins/php/weechat-php-api.c b/src/plugins/php/weechat-php-api.c
index f648efd41..e08dbde3a 100644
--- a/src/plugins/php/weechat-php-api.c
+++ b/src/plugins/php/weechat-php-api.c
@@ -67,8 +67,6 @@
     plugin_script_str2ptr (weechat_php_plugin,                          \
                            PHP_CURRENT_SCRIPT_NAME,                     \
                            php_function_name, __string)
-#define API_STATIC_STRING(__string)                                     \
-    plugin_script_get_static_string(&php_data, __string);
 #define API_RETURN_OK RETURN_LONG((long)1)
 #define API_RETURN_ERROR RETURN_LONG((long)0)
 #define API_RETURN_EMPTY RETURN_NULL()
@@ -2889,7 +2887,7 @@ API_FUNC(hook_modifier_exec)
     API_RETURN_STRING_FREE(result);
 }
 
-static const char *
+static char *
 weechat_php_api_hook_info_cb (const void *pointer,
                               void *data,
                               const char *info_name,
@@ -2904,7 +2902,7 @@ weechat_php_api_hook_info_cb (const void *pointer,
     weechat_php_cb (pointer, data, func_argv, "sss",
                     WEECHAT_SCRIPT_EXEC_STRING, &rc);
 
-    return API_STATIC_STRING(rc);
+    return rc;
 }
 
 API_FUNC(hook_info)
@@ -4181,8 +4179,7 @@ API_FUNC(command_options)
 API_FUNC(info_get)
 {
     zend_string *z_info_name, *z_arguments;
-    char *info_name, *arguments;
-    const char *result;
+    char *info_name, *arguments, *result;
 
     API_INIT_FUNC(1, "info_get", API_RETURN_EMPTY);
     if (zend_parse_parameters (ZEND_NUM_ARGS(), "SS", &z_info_name,
@@ -4194,7 +4191,7 @@ API_FUNC(info_get)
     result = weechat_info_get ((const char *)info_name,
                                (const char *)arguments);
 
-    API_RETURN_STRING(result);
+    API_RETURN_STRING_FREE(result);
 }
 
 API_FUNC(info_get_hashtable)
diff --git a/src/plugins/php/weechat-php.c b/src/plugins/php/weechat-php.c
index 85dd6b3ea..5702d919f 100644
--- a/src/plugins/php/weechat-php.c
+++ b/src/plugins/php/weechat-php.c
@@ -65,7 +65,6 @@ int php_eval_mode = 0;
 int php_eval_send_input = 0;
 int php_eval_exec_commands = 0;
 struct t_gui_buffer *php_eval_buffer = NULL;
-char *php_eval_output = NULL;
 
 struct t_plugin_script *php_scripts = NULL;
 struct t_plugin_script *last_php_script = NULL;
@@ -1062,12 +1061,12 @@ weechat_php_hdata_cb (const void *pointer, void *data,
  * Returns PHP info "php_eval".
  */
 
-const char *
+char *
 weechat_php_info_eval_cb (const void *pointer, void *data,
                           const char *info_name,
                           const char *arguments)
 {
-    static const char *not_implemented = "not yet implemented";
+    const char *not_implemented = "not yet implemented";
 
     /* make C compiler happy */
     (void) pointer;
@@ -1075,7 +1074,7 @@ weechat_php_info_eval_cb (const void *pointer, void *data,
     (void) info_name;
     (void) arguments;
 
-    return not_implemented;
+    return strdup (not_implemented);
 }
 
 /*
@@ -1351,8 +1350,6 @@ weechat_plugin_end (struct t_weechat_plugin *plugin)
     if (php_action_autoload_list)
         free (php_action_autoload_list);
     /* weechat_string_dyn_free (php_buffer_output, 1); */
-    if (php_eval_output)
-        free (php_eval_output);
 
     return WEECHAT_RC_OK;
 }
diff --git a/src/plugins/plugin-api-info.c b/src/plugins/plugin-api-info.c
index 31abcaaca..f92d0afa9 100644
--- a/src/plugins/plugin-api-info.c
+++ b/src/plugins/plugin-api-info.c
@@ -60,30 +60,33 @@
  * Returns WeeChat info "version".
  */
 
-const char *
+char *
 plugin_api_info_version_cb (const void *pointer, void *data,
                             const char *info_name,
                             const char *arguments)
 {
+    const char *version;
+
     /* make C compiler happy */
     (void) pointer;
     (void) data;
     (void) info_name;
     (void) arguments;
 
-    return version_get_version ();
+    version = version_get_version ();
+    return (version) ? strdup (version) : NULL;
 }
 
 /*
  * Returns WeeChat info "version_number".
  */
 
-const char *
+char *
 plugin_api_info_version_number_cb (const void *pointer, void *data,
                                    const char *info_name,
                                    const char *arguments)
 {
-    static char version_number[32] = { '\0' };
+    char version_number[32];
 
     /* make C compiler happy */
     (void) pointer;
@@ -91,60 +94,63 @@ plugin_api_info_version_number_cb (const void *pointer, void *data,
     (void) info_name;
     (void) arguments;
 
-    if (!version_number[0])
-    {
-        snprintf (version_number, sizeof (version_number), "%d",
-                  util_version_number (version_get_version ()));
-    }
-    return version_number;
+    snprintf (version_number, sizeof (version_number), "%d",
+              util_version_number (version_get_version ()));
+    return strdup (version_number);
 }
 
 /*
  * Returns WeeChat info "version_git".
  */
 
-const char *
+char *
 plugin_api_info_version_git_cb (const void *pointer, void *data,
                                 const char *info_name,
                                 const char *arguments)
 {
+    const char *version;
+
     /* make C compiler happy */
     (void) pointer;
     (void) data;
     (void) info_name;
     (void) arguments;
 
-    return version_get_git ();
+    version = version_get_git ();
+    return (version) ? strdup (version) : NULL;
 }
 
 /*
  * Returns WeeChat info "date".
  */
 
-const char *
+char *
 plugin_api_info_date_cb (const void *pointer, void *data,
                          const char *info_name,
                          const char *arguments)
 {
+    const char *version;
+
     /* make C compiler happy */
     (void) pointer;
     (void) data;
     (void) info_name;
     (void) arguments;
 
-    return version_get_compilation_date_time ();
+    version = version_get_compilation_date_time ();
+    return (version) ? strdup (version) : NULL;
 }
 
 /*
  * Returns WeeChat info "pid".
  */
 
-const char *
+char *
 plugin_api_info_pid_cb (const void *pointer, void *data,
                         const char *info_name,
                         const char *arguments)
 {
-    static char value[32];
+    char value[32];
 
     /* make C compiler happy */
     (void) pointer;
@@ -153,14 +159,14 @@ plugin_api_info_pid_cb (const void *pointer, void *data,
     (void) arguments;
 
     snprintf (value, sizeof (value), "%d", (int)getpid ());
-    return value;
+    return strdup (value);
 }
 
 /*
  * Returns WeeChat info "dir_separator".
  */
 
-const char *
+char *
 plugin_api_info_dir_separator_cb (const void *pointer, void *data,
                                   const char *info_name,
                                   const char *arguments)
@@ -171,19 +177,19 @@ plugin_api_info_dir_separator_cb (const void *pointer, void *data,
     (void) info_name;
     (void) arguments;
 
-    return DIR_SEPARATOR;
+    return strdup (DIR_SEPARATOR);
 }
 
 /*
  * Returns WeeChat info "weechat_dir".
  */
 
-const char *
+char *
 plugin_api_info_weechat_dir_cb (const void *pointer, void *data,
                                 const char *info_name,
                                 const char *arguments)
 {
-    static char weechat_dir_absolute_path[PATH_MAX] = { '\0' };
+    char weechat_dir_absolute_path[PATH_MAX];
 
     /* make C compiler happy */
     (void) pointer;
@@ -191,20 +197,18 @@ plugin_api_info_weechat_dir_cb (const void *pointer, void *data,
     (void) info_name;
     (void) arguments;
 
-    if (!weechat_dir_absolute_path[0])
-    {
-        if (!realpath (weechat_home, weechat_dir_absolute_path))
-            return NULL;
-    }
-    return (weechat_dir_absolute_path[0]) ?
-        weechat_dir_absolute_path : weechat_home;
+    if (!realpath (weechat_home, weechat_dir_absolute_path))
+        return NULL;
+
+    return strdup ((weechat_dir_absolute_path[0]) ?
+                   weechat_dir_absolute_path : weechat_home);
 }
 
 /*
  * Returns WeeChat info "weechat_libdir".
  */
 
-const char *
+char *
 plugin_api_info_weechat_libdir_cb (const void *pointer, void *data,
                                    const char *info_name,
                                    const char *arguments)
@@ -215,14 +219,14 @@ plugin_api_info_weechat_libdir_cb (const void *pointer, void *data,
     (void) info_name;
     (void) arguments;
 
-    return WEECHAT_LIBDIR;
+    return strdup (WEECHAT_LIBDIR);
 }
 
 /*
  * Returns WeeChat info "weechat_sharedir".
  */
 
-const char *
+char *
 plugin_api_info_weechat_sharedir_cb (const void *pointer, void *data,
                                      const char *info_name,
                                      const char *arguments)
@@ -233,14 +237,14 @@ plugin_api_info_weechat_sharedir_cb (const void *pointer, void *data,
     (void) info_name;
     (void) arguments;
 
-    return WEECHAT_SHAREDIR;
+    return strdup (WEECHAT_SHAREDIR);
 }
 
 /*
  * Returns WeeChat info "weechat_localedir".
  */
 
-const char *
+char *
 plugin_api_info_weechat_localedir_cb (const void *pointer, void *data,
                                       const char *info_name,
                                       const char *arguments)
@@ -251,14 +255,14 @@ plugin_api_info_weechat_localedir_cb (const void *pointer, void *data,
     (void) info_name;
     (void) arguments;
 
-    return LOCALEDIR;
+    return strdup (LOCALEDIR);
 }
 
 /*
  * Returns WeeChat info "weechat_site".
  */
 
-const char *
+char *
 plugin_api_info_weechat_site_cb (const void *pointer, void *data,
                                  const char *info_name,
                                  const char *arguments)
@@ -269,14 +273,14 @@ plugin_api_info_weechat_site_cb (const void *pointer, void *data,
     (void) info_name;
     (void) arguments;
 
-    return WEECHAT_WEBSITE;
+    return strdup (WEECHAT_WEBSITE);
 }
 
 /*
  * Returns WeeChat info "weechat_site_download".
  */
 
-const char *
+char *
 plugin_api_info_weechat_site_download_cb (const void *pointer, void *data,
                                           const char *info_name,
                                           const char *arguments)
@@ -287,19 +291,19 @@ plugin_api_info_weechat_site_download_cb (const void *pointer, void *data,
     (void) info_name;
     (void) arguments;
 
-    return WEECHAT_WEBSITE_DOWNLOAD;
+    return strdup (WEECHAT_WEBSITE_DOWNLOAD);
 }
 
 /*
  * Returns WeeChat info "weechat_upgrading".
  */
 
-const char *
+char *
 plugin_api_info_weechat_upgrading_cb (const void *pointer, void *data,
                                       const char *info_name,
                                       const char *arguments)
 {
-    static char value[32];
+    char value[32];
 
     /* make C compiler happy */
     (void) pointer;
@@ -308,14 +312,14 @@ plugin_api_info_weechat_upgrading_cb (const void *pointer, void *data,
     (void) arguments;
 
     snprintf (value, sizeof (value), "%d", weechat_upgrading);
-    return value;
+    return strdup (value);
 }
 
 /*
  * Returns WeeChat info "charset_terminal".
  */
 
-const char *
+char *
 plugin_api_info_charset_terminal_cb (const void *pointer, void *data,
                                      const char *info_name,
                                      const char *arguments)
@@ -326,14 +330,14 @@ plugin_api_info_charset_terminal_cb (const void *pointer, void *data,
     (void) info_name;
     (void) arguments;
 
-    return weechat_local_charset;
+    return (weechat_local_charset) ? strdup (weechat_local_charset) : NULL;
 }
 
 /*
  * Returns WeeChat info "charset_internal".
  */
 
-const char *
+char *
 plugin_api_info_charset_internal_cb (const void *pointer, void *data,
                                      const char *info_name,
                                      const char *arguments)
@@ -344,38 +348,41 @@ plugin_api_info_charset_internal_cb (const void *pointer, void *data,
     (void) info_name;
     (void) arguments;
 
-    return WEECHAT_INTERNAL_CHARSET;
+    return strdup (WEECHAT_INTERNAL_CHARSET);
 }
 
 /*
  * Returns WeeChat info "locale".
  */
 
-const char *
+char *
 plugin_api_info_locale_cb (const void *pointer, void *data,
                            const char *info_name,
                            const char *arguments)
 {
+    char *locale;
+
     /* make C compiler happy */
     (void) pointer;
     (void) data;
     (void) info_name;
     (void) arguments;
 
-    return setlocale (LC_MESSAGES, NULL);
+    locale = setlocale (LC_MESSAGES, NULL);
+    return (locale) ? strdup (locale) : NULL;
 }
 
 /*
  * Returns WeeChat info "inactivity".
  */
 
-const char *
+char *
 plugin_api_info_inactivity_cb (const void *pointer, void *data,
                                const char *info_name,
                                const char *arguments)
 {
     time_t inactivity;
-    static char value[32];
+    char value[32];
 
     /* make C compiler happy */
     (void) pointer;
@@ -387,20 +394,22 @@ plugin_api_info_inactivity_cb (const void *pointer, void *data,
         inactivity = 0;
     else
         inactivity = time (NULL) - gui_key_last_activity_time;
+
     snprintf (value, sizeof (value), "%lld", (long long)inactivity);
-    return value;
+
+    return strdup (value);
 }
 
 /*
  * Returns WeeChat info "filters_enabled".
  */
 
-const char *
+char *
 plugin_api_info_filters_enabled_cb (const void *pointer, void *data,
                                     const char *info_name,
                                     const char *arguments)
 {
-    static char value[32];
+    char value[32];
 
     /* make C compiler happy */
     (void) pointer;
@@ -409,19 +418,19 @@ plugin_api_info_filters_enabled_cb (const void *pointer, void *data,
     (void) arguments;
 
     snprintf (value, sizeof (value), "%d", gui_filters_enabled);
-    return value;
+    return strdup (value);
 }
 
 /*
  * Returns WeeChat info "cursor_mode".
  */
 
-const char *
+char *
 plugin_api_info_cursor_mode_cb (const void *pointer, void *data,
                                 const char *info_name,
                                 const char *arguments)
 {
-    static char value[32];
+    char value[32];
 
     /* make C compiler happy */
     (void) pointer;
@@ -430,19 +439,19 @@ plugin_api_info_cursor_mode_cb (const void *pointer, void *data,
     (void) arguments;
 
     snprintf (value, sizeof (value), "%d", gui_cursor_mode);
-    return value;
+    return strdup (value);
 }
 
 /*
  * Returns WeeChat info "term_width".
  */
 
-const char *
+char *
 plugin_api_info_term_width_cb (const void *pointer, void *data,
                                const char *info_name,
                                const char *arguments)
 {
-    static char value[32];
+    char value[32];
 
     /* make C compiler happy */
     (void) pointer;
@@ -451,19 +460,19 @@ plugin_api_info_term_width_cb (const void *pointer, void *data,
     (void) arguments;
 
     snprintf (value, sizeof (value), "%d", gui_window_get_width ());
-    return value;
+    return strdup (value);
 }
 
 /*
  * Returns WeeChat info "term_height".
  */
 
-const char *
+char *
 plugin_api_info_term_height_cb (const void *pointer, void *data,
                                 const char *info_name,
                                 const char *arguments)
 {
-    static char value[32];
+    char value[32];
 
     /* make C compiler happy */
     (void) pointer;
@@ -472,14 +481,14 @@ plugin_api_info_term_height_cb (const void *pointer, void *data,
     (void) arguments;
 
     snprintf (value, sizeof (value), "%d", gui_window_get_height ());
-    return value;
+    return strdup (value);
 }
 
 /*
  * Returns WeeChat info "color_ansi_regex".
  */
 
-const char *
+char *
 plugin_api_info_color_ansi_regex_cb (const void *pointer, void *data,
                                      const char *info_name,
                                      const char *arguments)
@@ -490,19 +499,19 @@ plugin_api_info_color_ansi_regex_cb (const void *pointer, void *data,
     (void) info_name;
     (void) arguments;
 
-    return GUI_COLOR_REGEX_ANSI_DECODE;
+    return strdup (GUI_COLOR_REGEX_ANSI_DECODE);
 }
 
 /*
  * Returns WeeChat info "color_term2rgb".
  */
 
-const char *
+char *
 plugin_api_info_color_term2rgb_cb (const void *pointer, void *data,
                                    const char *info_name,
                                    const char *arguments)
 {
-    static char value[32];
+    char value[32];
 
     /* make C compiler happy */
     (void) pointer;
@@ -515,21 +524,20 @@ plugin_api_info_color_term2rgb_cb (const void *pointer, void *data,
     snprintf (value, sizeof (value),
               "%d",
               gui_color_convert_term_to_rgb (atoi (arguments)));
-    return value;
+    return strdup (value);
 }
 
 /*
  * Returns WeeChat info "color_rgb2term".
  */
 
-const char *
+char *
 plugin_api_info_color_rgb2term_cb (const void *pointer, void *data,
                                    const char *info_name,
                                    const char *arguments)
 {
-    static char value[32];
+    char value[32], *pos, *color;
     int rgb, limit;
-    char *pos, *color;
 
     /* make C compiler happy */
     (void) pointer;
@@ -554,57 +562,64 @@ plugin_api_info_color_rgb2term_cb (const void *pointer, void *data,
     {
         rgb = atoi (arguments);
     }
+
     snprintf (value, sizeof (value),
               "%d",
               gui_color_convert_rgb_to_term (rgb, limit));
 
-    return value;
+    return strdup (value);
 }
 
 /*
  * Returns nick color code for a nickname.
  */
 
-const char *
+char *
 plugin_api_info_nick_color_cb (const void *pointer, void *data,
                                const char *info_name,
                                const char *arguments)
 {
+    const char *ptr_color;
+
     /* make C compiler happy */
     (void) pointer;
     (void) data;
     (void) info_name;
 
-    return gui_nick_find_color (arguments);
+    ptr_color = gui_nick_find_color (arguments);
+    return (ptr_color) ? strdup (ptr_color) : NULL;
 }
 
 /*
  * Returns nick color name for a nickname.
  */
 
-const char *
+char *
 plugin_api_info_nick_color_name_cb (const void *pointer, void *data,
                                     const char *info_name,
                                     const char *arguments)
 {
+    const char *ptr_color;
+
     /* make C compiler happy */
     (void) pointer;
     (void) data;
     (void) info_name;
 
-    return gui_nick_find_color_name (arguments);
+    ptr_color = gui_nick_find_color_name (arguments);
+    return (ptr_color) ? strdup (ptr_color) : NULL;
 }
 
 /*
  * Returns WeeChat info "uptime".
  */
 
-const char *
+char *
 plugin_api_info_uptime_cb (const void *pointer, void *data,
                            const char *info_name,
                            const char *arguments)
 {
-    static char value[32];
+    char value[32];
     time_t total_seconds;
     int days, hours, minutes, seconds;
 
@@ -619,7 +634,7 @@ plugin_api_info_uptime_cb (const void *pointer, void *data,
         util_get_uptime (NULL, &days, &hours, &minutes, &seconds);
         snprintf (value, sizeof (value), "%d:%02d:%02d:%02d",
                   days, hours, minutes, seconds);
-        return value;
+        return strdup (value);
     }
 
     if (strcmp (arguments, "days") == 0)
@@ -627,7 +642,7 @@ plugin_api_info_uptime_cb (const void *pointer, void *data,
         /* return the number of days */
         util_get_uptime (NULL, &days, NULL, NULL, NULL);
         snprintf (value, sizeof (value), "%d", days);
-        return value;
+        return strdup (value);
     }
 
     if (strcmp (arguments, "seconds") == 0)
@@ -635,7 +650,7 @@ plugin_api_info_uptime_cb (const void *pointer, void *data,
         /* return the number of seconds */
         util_get_uptime (&total_seconds, NULL, NULL, NULL, NULL);
         snprintf (value, sizeof (value), "%lld", (long long)total_seconds);
-        return value;
+        return strdup (value);
     }
 
     return NULL;
@@ -648,14 +663,13 @@ plugin_api_info_uptime_cb (const void *pointer, void *data,
  * Arguments: "secret,timestamp,digits" (timestamp and digits are optional).
  */
 
-const char *
+char *
 plugin_api_info_totp_generate_cb (const void *pointer, void *data,
                                   const char *info_name,
                                   const char *arguments)
 {
-    static char value[32];
     char **argv, *ptr_secret, *error, *totp;
-    int argc, digits, length;
+    int argc, digits;
     long number;
     time_t totp_time;
 
@@ -703,14 +717,9 @@ plugin_api_info_totp_generate_cb (const void *pointer, void *data,
     if (!totp)
         goto error;
 
-    length = snprintf (value, sizeof (value), "%s", totp);
-    if (length != digits)
-        goto error;
-
     string_free_split (argv);
-    free (totp);
 
-    return value;
+    return totp;
 
 error:
     if (argv)
@@ -727,13 +736,12 @@ error:
  * Arguments: "secret,otp,timestamp,window" (timestamp and window are optional).
  */
 
-const char *
+char *
 plugin_api_info_totp_validate_cb (const void *pointer, void *data,
                                   const char *info_name,
                                   const char *arguments)
 {
-    static char value[16];
-    char **argv, *ptr_secret, *ptr_otp, *error;
+    char value[16], **argv, *ptr_secret, *ptr_otp, *error;
     int argc, window, rc;
     long number;
     time_t totp_time;
@@ -784,7 +792,7 @@ plugin_api_info_totp_validate_cb (const void *pointer, void *data,
 
     string_free_split (argv);
 
-    return value;
+    return strdup (value);
 
 error:
     if (argv)
diff --git a/src/plugins/plugin-script-api.c b/src/plugins/plugin-script-api.c
index 3bf1fd7ca..d07ac85ff 100644
--- a/src/plugins/plugin-script-api.c
+++ b/src/plugins/plugin-script-api.c
@@ -1001,10 +1001,10 @@ plugin_script_api_hook_info (struct t_weechat_plugin *weechat_plugin,
                              const char *info_name,
                              const char *description,
                              const char *args_description,
-                             const char *(*callback)(const void *pointer,
-                                                     void *data,
-                                                     const char *info_name,
-                                                     const char *arguments),
+                             char *(*callback)(const void *pointer,
+                                               void *data,
+                                               const char *info_name,
+                                               const char *arguments),
                              const char *function,
                              const char *data)
 {
diff --git a/src/plugins/plugin-script-api.h b/src/plugins/plugin-script-api.h
index 55f6d55f3..955b68693 100644
--- a/src/plugins/plugin-script-api.h
+++ b/src/plugins/plugin-script-api.h
@@ -289,10 +289,10 @@ extern struct t_hook *plugin_script_api_hook_info (struct t_weechat_plugin *weec
                                                    const char *info_name,
                                                    const char *description,
                                                    const char *args_description,
-                                                   const char *(*callback)(const void *pointer,
-                                                                           void *data,
-                                                                           const char *info_name,
-                                                                           const char *arguments),
+                                                   char *(*callback)(const void *pointer,
+                                                                     void *data,
+                                                                     const char *info_name,
+                                                                     const char *arguments),
                                                    const char *function,
                                                    const char *data);
 extern struct t_hook *plugin_script_api_hook_info_hashtable (struct t_weechat_plugin *weechat_plugin,
diff --git a/src/plugins/plugin-script.c b/src/plugins/plugin-script.c
index 55076d4e7..8dff7acca 100644
--- a/src/plugins/plugin-script.c
+++ b/src/plugins/plugin-script.c
@@ -89,12 +89,13 @@ plugin_script_signal_debug_libs_cb (const void *pointer, void *data,
  * Callback for info "xxx_interpreter".
  */
 
-const char *
+char *
 plugin_script_info_interpreter_cb (const void *pointer, void *data,
                                    const char *info_name,
                                    const char *arguments)
 {
     struct t_weechat_plugin *weechat_plugin;
+    const char *ptr_interpreter;
 
     /* make C compiler happy */
     (void) data;
@@ -103,20 +104,22 @@ plugin_script_info_interpreter_cb (const void *pointer, void *data,
 
     weechat_plugin = (struct t_weechat_plugin *)pointer;
 
-    return weechat_hashtable_get (weechat_plugin->variables,
-                                  "interpreter_name");
+    ptr_interpreter = weechat_hashtable_get (weechat_plugin->variables,
+                                             "interpreter_name");
+    return (ptr_interpreter) ? strdup (ptr_interpreter) : NULL;
 }
 
 /*
  * Callback for info "xxx_version".
  */
 
-const char *
+char *
 plugin_script_info_version_cb (const void *pointer, void *data,
                                const char *info_name,
                                const char *arguments)
 {
     struct t_weechat_plugin *weechat_plugin;
+    const char *ptr_version;
 
     /* make C compiler happy */
     (void) data;
@@ -125,8 +128,9 @@ plugin_script_info_version_cb (const void *pointer, void *data,
 
     weechat_plugin = (struct t_weechat_plugin *)pointer;
 
-    return weechat_hashtable_get (weechat_plugin->variables,
-                                  "interpreter_version");
+    ptr_version = weechat_hashtable_get (weechat_plugin->variables,
+                                         "interpreter_version");
+    return (ptr_version) ? strdup (ptr_version) : NULL;
 }
 
 /*
@@ -171,13 +175,6 @@ plugin_script_init (struct t_weechat_plugin *weechat_plugin,
     char *action_signals[] = { "install", "remove", "autoload", NULL };
     int i, auto_load_scripts;
 
-    /* initialize static strings */
-    plugin_data->index_static_string = 0;
-    for (i = 0; i < WEECHAT_SCRIPT_STATIC_STRINGS; i++)
-    {
-        plugin_data->static_string[i] = NULL;
-    }
-
     /* initialize script configuration file (file: "<language>.conf") */
     plugin_script_config_init (weechat_plugin, plugin_data);
 
@@ -395,29 +392,6 @@ invalid:
 }
 
 /*
- * Gets a "static string": a string allocated that will be freed later
- * (or when the plugin is unloaded).
- *
- * The "string" argument must have been allocated by free (or strdup, ...)
- * and will be automatically freed later.
- */
-
-char *
-plugin_script_get_static_string (struct t_plugin_script_data *plugin_data,
-                                 char *string)
-{
-    plugin_data->index_static_string = (plugin_data->index_static_string + 1) %
-        WEECHAT_SCRIPT_STATIC_STRINGS;
-
-    if (plugin_data->static_string[plugin_data->index_static_string])
-        free (plugin_data->static_string[plugin_data->index_static_string]);
-
-    plugin_data->static_string[plugin_data->index_static_string] = string;
-
-    return plugin_data->static_string[plugin_data->index_static_string];
-}
-
-/*
  * Builds concatenated function name and data (both are strings).
  * The result will be sent to callbacks.
  */
@@ -487,8 +461,7 @@ plugin_script_auto_load (struct t_weechat_plugin *weechat_plugin,
                          void (*callback)(void *data,
                                           const char *filename))
 {
-    const char *dir_home;
-    char *dir_name;
+    char *dir_home, *dir_name;
     int dir_length;
 
     /* build directory, adding WeeChat home */
@@ -498,12 +471,16 @@ plugin_script_auto_load (struct t_weechat_plugin *weechat_plugin,
     dir_length = strlen (dir_home) + strlen (weechat_plugin->name) + 16;
     dir_name = malloc (dir_length);
     if (!dir_name)
+    {
+        free (dir_home);
         return;
+    }
 
     snprintf (dir_name, dir_length,
               "%s/%s/autoload", dir_home, weechat_plugin->name);
     weechat_exec_on_files (dir_name, 0, 0, callback, NULL);
 
+    free (dir_home);
     free (dir_name);
 }
 
@@ -565,8 +542,7 @@ char *
 plugin_script_search_path (struct t_weechat_plugin *weechat_plugin,
                            const char *filename)
 {
-    char *final_name;
-    const char *dir_home, *dir_system;
+    char *final_name, *dir_home, *dir_system;
     int length;
     struct stat st;
 
@@ -586,7 +562,10 @@ plugin_script_search_path (struct t_weechat_plugin *weechat_plugin,
                       "%s/%s/autoload/%s",
                       dir_home, weechat_plugin->name, filename);
             if ((stat (final_name, &st) == 0) && (st.st_size > 0))
+            {
+                free (dir_home);
                 return final_name;
+            }
             free (final_name);
         }
 
@@ -599,7 +578,10 @@ plugin_script_search_path (struct t_weechat_plugin *weechat_plugin,
             snprintf (final_name, length,
                       "%s/%s/%s", dir_home, weechat_plugin->name, filename);
             if ((stat (final_name, &st) == 0) && (st.st_size > 0))
+            {
+                free (dir_home);
                 return final_name;
+            }
             free (final_name);
         }
 
@@ -611,9 +593,13 @@ plugin_script_search_path (struct t_weechat_plugin *weechat_plugin,
             snprintf (final_name, length,
                       "%s/%s", dir_home, filename);
             if ((stat (final_name, &st) == 0) && (st.st_size > 0))
+            {
+                free (dir_home);
                 return final_name;
+            }
             free (final_name);
         }
+        free (dir_home);
     }
 
     /* try WeeChat system dir */
@@ -628,9 +614,13 @@ plugin_script_search_path (struct t_weechat_plugin *weechat_plugin,
             snprintf (final_name,length,
                       "%s/%s/%s", dir_system, weechat_plugin->name, filename);
             if ((stat (final_name, &st) == 0) && (st.st_size > 0))
+            {
+                free (dir_system);
                 return final_name;
+            }
             free (final_name);
         }
+        free (dir_system);
     }
 
     return strdup (filename);
@@ -1228,8 +1218,7 @@ plugin_script_action_install (struct t_weechat_plugin *weechat_plugin,
                               char **list)
 {
     char **argv, *name, *ptr_base_name, *base_name, *new_path, *autoload_path;
-    char *symlink_path, str_signal[128], *ptr_list;
-    const char *dir_home, *dir_separator;
+    char *symlink_path, str_signal[128], *ptr_list, *dir_home, *dir_separator;
     int argc, i, length, rc, autoload, existing_script, script_loaded;
     struct t_plugin_script *ptr_script;
 
@@ -1330,6 +1319,8 @@ plugin_script_action_install (struct t_weechat_plugin *weechat_plugin,
                                         free (symlink_path);
                                     }
                                     free (autoload_path);
+                                    if (dir_separator)
+                                        free (dir_separator);
                                 }
                             }
 
@@ -1356,6 +1347,8 @@ plugin_script_action_install (struct t_weechat_plugin *weechat_plugin,
                         free (new_path);
                     }
                     free (base_name);
+                    if (dir_home)
+                        free (dir_home);
                 }
                 free (name);
             }
@@ -1449,8 +1442,7 @@ plugin_script_action_autoload (struct t_weechat_plugin *weechat_plugin,
                                char **list)
 {
     char **argv, *name, *ptr_base_name, *base_name, *autoload_path;
-    char *symlink_path, *ptr_list;
-    const char *dir_home, *dir_separator;
+    char *symlink_path, *ptr_list, *dir_home, *dir_separator;
     int argc, i, length, rc, autoload;
 
     if (!*list)
@@ -1523,6 +1515,8 @@ plugin_script_action_autoload (struct t_weechat_plugin *weechat_plugin,
                                 (void) rc;
                                 free (symlink_path);
                             }
+                            if (dir_separator)
+                                free (dir_separator);
                         }
                         else
                         {
@@ -1531,6 +1525,8 @@ plugin_script_action_autoload (struct t_weechat_plugin *weechat_plugin,
                         free (autoload_path);
                     }
                     free (base_name);
+                    if (dir_home)
+                        free (dir_home);
                 }
                 free (name);
             }
@@ -1784,7 +1780,7 @@ void
 plugin_script_end (struct t_weechat_plugin *weechat_plugin,
                    struct t_plugin_script_data *plugin_data)
 {
-    int scripts_loaded, i;
+    int scripts_loaded;
 
     /* unload all scripts */
     scripts_loaded = (*(plugin_data->scripts)) ? 1 : 0;
@@ -1798,16 +1794,6 @@ plugin_script_end (struct t_weechat_plugin *weechat_plugin,
     /* write config file (file: "<language>.conf") */
     weechat_config_write (*(plugin_data->config_file));
     weechat_config_free (*(plugin_data->config_file));
-
-    /* free static strings */
-    for (i = 0; i < WEECHAT_SCRIPT_STATIC_STRINGS; i++)
-    {
-        if (plugin_data->static_string[i])
-        {
-            free (plugin_data->static_string[i]);
-            plugin_data->static_string[i] = NULL;
-        }
-    }
 }
 
 /*
diff --git a/src/plugins/plugin-script.h b/src/plugins/plugin-script.h
index 796c4d1a9..d94fd658e 100644
--- a/src/plugins/plugin-script.h
+++ b/src/plugins/plugin-script.h
@@ -33,8 +33,6 @@ enum t_weechat_script_exec_type
 
 #define WEECHAT_SCRIPT_HASHTABLE_DEFAULT_SIZE 16
 
-#define WEECHAT_SCRIPT_STATIC_STRINGS 32
-
 #define WEECHAT_SCRIPT_EVAL_NAME "__eval__"
 
 #define WEECHAT_SCRIPT_MSG_NOT_INIT(__current_script,                   \
@@ -80,8 +78,6 @@ struct t_plugin_script_data
     struct t_config_option **config_look_eval_keep_context;
     struct t_plugin_script **scripts;
     struct t_plugin_script **last_script;
-    char *static_string[WEECHAT_SCRIPT_STATIC_STRINGS];
-    int index_static_string;
 
     /* callbacks */
     int (*callback_command) (const void *pointer, void *data,
@@ -94,10 +90,10 @@ struct t_plugin_script_data
     struct t_hdata *(*callback_hdata) (const void *pointer,
                                        void *data,
                                        const char *hdata_name);
-    const char *(*callback_info_eval) (const void *pointer,
-                                       void *data,
-                                       const char *info_name,
-                                       const char *arguments);
+    char *(*callback_info_eval) (const void *pointer,
+                                 void *data,
+                                 const char *info_name,
+                                 const char *arguments);
     struct t_infolist *(*callback_infolist) (const void *pointer,
                                              void *data,
                                              const char *infolist_name,
@@ -129,8 +125,6 @@ extern void *plugin_script_str2ptr (struct t_weechat_plugin *weechat_plugin,
                                     const char *script_name,
                                     const char *function_name,
                                     const char *pointer_str);
-extern char *plugin_script_get_static_string (struct t_plugin_script_data *plugin_data,
-                                              char *string);
 extern char *plugin_script_build_function_and_data (const char *function,
                                                     const char *data);
 extern void plugin_script_get_function_and_data (void *callback_data,
diff --git a/src/plugins/python/weechat-python-api.c b/src/plugins/python/weechat-python-api.c
index 572ce70aa..74ca1b33f 100644
--- a/src/plugins/python/weechat-python-api.c
+++ b/src/plugins/python/weechat-python-api.c
@@ -59,8 +59,6 @@
     plugin_script_str2ptr (weechat_python_plugin,                       \
                            PYTHON_CURRENT_SCRIPT_NAME,                  \
                            python_function_name, __string)
-#define API_STATIC_STRING(__string)                                     \
-    plugin_script_get_static_string(&python_data, __string);
 #define API_RETURN_OK return PyLong_FromLong((long)1)
 #define API_RETURN_ERROR return PyLong_FromLong ((long)0)
 #define API_RETURN_EMPTY                                                \
@@ -3024,14 +3022,14 @@ API_FUNC(hook_modifier_exec)
     API_RETURN_STRING_FREE(result);
 }
 
-const char *
+char *
 weechat_python_api_hook_info_cb (const void *pointer, void *data,
                                  const char *info_name,
                                  const char *arguments)
 {
     struct t_plugin_script *script;
     void *func_argv[3];
-    char empty_arg[1] = { '\0' }, *result;
+    char empty_arg[1] = { '\0' };
     const char *ptr_function, *ptr_data;
 
     script = (struct t_plugin_script *)pointer;
@@ -3043,12 +3041,10 @@ weechat_python_api_hook_info_cb (const void *pointer, void *data,
         func_argv[1] = (info_name) ? (char *)info_name : empty_arg;
         func_argv[2] = (arguments) ? (char *)arguments : empty_arg;
 
-        result = (char *)weechat_python_exec (script,
-                                              WEECHAT_SCRIPT_EXEC_STRING,
-                                              ptr_function,
-                                              "sss", func_argv);
-
-        return API_STATIC_STRING(result);
+        return (char *)weechat_python_exec (script,
+                                            WEECHAT_SCRIPT_EXEC_STRING,
+                                            ptr_function,
+                                            "sss", func_argv);
     }
 
     return NULL;
@@ -4278,8 +4274,8 @@ API_FUNC(command_options)
 
 API_FUNC(info_get)
 {
-    char *info_name, *arguments;
-    const char *result;
+    char *info_name, *arguments, *result;
+    PyObject *return_value;
 
     API_INIT_FUNC(1, "info_get", API_RETURN_EMPTY);
     info_name = NULL;
@@ -4289,7 +4285,7 @@ API_FUNC(info_get)
 
     result = weechat_info_get (info_name, arguments);
 
-    API_RETURN_STRING(result);
+    API_RETURN_STRING_FREE(result);
 }
 
 API_FUNC(info_get_hashtable)
diff --git a/src/plugins/python/weechat-python.c b/src/plugins/python/weechat-python.c
index 8aeacec0c..f36899dce 100644
--- a/src/plugins/python/weechat-python.c
+++ b/src/plugins/python/weechat-python.c
@@ -57,7 +57,6 @@ int python_eval_mode = 0;
 int python_eval_send_input = 0;
 int python_eval_exec_commands = 0;
 struct t_gui_buffer *python_eval_buffer = NULL;
-char *python_eval_output = NULL;
 #define PYTHON_EVAL_SCRIPT                                              \
     "import weechat\n"                                                  \
     "\n"                                                                \
@@ -144,8 +143,7 @@ char *python_action_autoload_list = NULL;
 char *
 weechat_python_get_python2_bin ()
 {
-    const char *dir_separator;
-    char *py2_bin, *path, **paths, bin[4096];
+    char *dir_separator, *py2_bin, *path, **paths, bin[4096];
     char *versions[] = { "2.7", "2.6", "2.5", "2.4", "2.3", "2.2", "2", NULL };
     int num_paths, i, j, rc;
     struct stat stat_buf;
@@ -185,6 +183,9 @@ weechat_python_get_python2_bin ()
         }
     }
 
+    if (dir_separator)
+        free (dir_separator);
+
     if (!py2_bin)
         py2_bin = strdup ("python");
 
@@ -753,7 +754,7 @@ weechat_python_load (const char *filename, const char *code)
 #endif /* PY_MAJOR_VERSION >= 3 */
     FILE *fp;
     PyObject *python_path, *path, *module_main, *globals, *rc;
-    const char *weechat_home;
+    char *weechat_home;
     char *str_home;
     int len;
 
@@ -842,6 +843,7 @@ weechat_python_load (const char *filename, const char *code)
             }
             free (str_home);
         }
+        free (weechat_home);
     }
 
     weechat_python_set_output ();
@@ -1332,7 +1334,7 @@ weechat_python_hdata_cb (const void *pointer, void *data,
  * Returns python info "python2_bin".
  */
 
-const char *
+char *
 weechat_python_info_python2_bin_cb (const void *pointer, void *data,
                                     const char *info_name,
                                     const char *arguments)
@@ -1355,30 +1357,30 @@ weechat_python_info_python2_bin_cb (const void *pointer, void *data,
             python2_bin = weechat_python_get_python2_bin ();
         }
     }
-    return python2_bin;
+    return (python2_bin) ? strdup (python2_bin) : NULL;
 }
 
 /*
  * Returns python info "python_eval".
  */
 
-const char *
+char *
 weechat_python_info_eval_cb (const void *pointer, void *data,
                              const char *info_name,
                              const char *arguments)
 {
+    char *output;
+
     /* make C compiler happy */
     (void) pointer;
     (void) data;
     (void) info_name;
 
     weechat_python_eval (NULL, 0, 0, (arguments) ? arguments : "");
-    if (python_eval_output)
-        free (python_eval_output);
-    python_eval_output = strdup (*python_buffer_output);
+    output = strdup (*python_buffer_output);
     weechat_string_dyn_copy (python_buffer_output, NULL);
 
-    return python_eval_output;
+    return output;
 }
 
 /*
@@ -1658,8 +1660,6 @@ weechat_plugin_end (struct t_weechat_plugin *plugin)
     if (python_action_autoload_list)
         free (python_action_autoload_list);
     weechat_string_dyn_free (python_buffer_output, 1);
-    if (python_eval_output)
-        free (python_eval_output);
 
     return WEECHAT_RC_OK;
 }
diff --git a/src/plugins/relay/irc/relay-irc.c b/src/plugins/relay/irc/relay-irc.c
index 506afb020..e54e52403 100644
--- a/src/plugins/relay/irc/relay-irc.c
+++ b/src/plugins/relay/irc/relay-irc.c
@@ -1322,11 +1322,12 @@ relay_irc_recv_command_capab (struct t_relay_client *client,
 void
 relay_irc_recv (struct t_relay_client *client, const char *data)
 {
-    char str_time[128], str_signal[128], str_server_channel[256];
-    char str_command[128], *target, **irc_argv, **irc_argv_eol, *pos, *password;
+    char str_time[128], str_signal[128], str_server_channel[256], *nick;
+    char *version, str_command[128], *target, **irc_argv, **irc_argv_eol;
+    char *pos, *password, *irc_is_channel, *info;
     const char *irc_command, *irc_channel, *irc_args, *irc_args2;
     int irc_argc, redirect_msg;
-    const char *nick, *irc_is_channel, *isupport, *info, *pos_password;
+    const char *isupport, *pos_password;
     struct t_hashtable *hash_parsed, *hash_redirect;
     struct t_infolist *infolist_server;
 
@@ -1512,7 +1513,10 @@ relay_irc_recv (struct t_relay_client *client, const char *data)
                 free (RELAY_IRC_DATA(client, nick));
                 RELAY_IRC_DATA(client, nick) = strdup (nick);
             }
+            if (nick)
+                free (nick);
 
+            version = weechat_info_get ("version", NULL);
             relay_irc_sendf (client,
                              ":%s 001 %s :Welcome to the Internet "
                              "Relay Chat Network %s!%s@proxy",
@@ -1525,7 +1529,7 @@ relay_irc_recv (struct t_relay_client *client, const char *data)
                              "weechat-relay-irc, running version %s",
                              RELAY_IRC_DATA(client, address),
                              RELAY_IRC_DATA(client, nick),
-                             weechat_info_get ("version", NULL));
+                             version);
             snprintf (str_time, sizeof (str_time), "%s",
                       ctime (&client->listen_start_time));
             if (str_time[0])
@@ -1540,7 +1544,9 @@ relay_irc_recv (struct t_relay_client *client, const char *data)
                              RELAY_IRC_DATA(client, address),
                              RELAY_IRC_DATA(client, nick),
                              RELAY_IRC_DATA(client, address),
-                             weechat_info_get ("version", NULL));
+                             version);
+            if (version)
+                free (version);
             infolist_server = weechat_infolist_get ("irc_server", NULL,
                                                     client->protocol_args);
             if (infolist_server)
@@ -1651,6 +1657,8 @@ relay_irc_recv (struct t_relay_client *client, const char *data)
                                       "/query %s %s",
                                       irc_channel, irc_args2);
             }
+            if (irc_is_channel)
+                free (irc_is_channel);
         }
         else if (!relay_irc_command_ignored (irc_command))
         {
@@ -1721,6 +1729,8 @@ relay_irc_recv (struct t_relay_client *client, const char *data)
                                                        "mode_user");
                             }
                         }
+                        if (info)
+                            free (info);
                     }
                 }
                 else if (weechat_strcasecmp (irc_command, "ison") == 0)
diff --git a/src/plugins/relay/relay-info.c b/src/plugins/relay/relay-info.c
index 24b68b236..3b33d88c1 100644
--- a/src/plugins/relay/relay-info.c
+++ b/src/plugins/relay/relay-info.c
@@ -32,14 +32,13 @@
  * Returns relay info "relay_client_count".
  */
 
-const char *
+char *
 relay_info_info_relay_client_count_cb (const void *pointer, void *data,
                                        const char *info_name,
                                        const char *arguments)
 {
-    static char str_count[32];
+    char str_count[32], **items;
     const char *ptr_count;
-    char **items;
     int count, protocol, status, num_items;
     struct t_relay_client *ptr_client;
 
@@ -110,7 +109,7 @@ end:
     if (items)
         weechat_string_free_split (items);
 
-    return ptr_count;
+    return (ptr_count) ? strdup (ptr_count) : NULL;
 }
 
 /*
diff --git a/src/plugins/relay/relay-network.c b/src/plugins/relay/relay-network.c
index 5d7b94ba2..85944044f 100644
--- a/src/plugins/relay/relay-network.c
+++ b/src/plugins/relay/relay-network.c
@@ -52,7 +52,7 @@ void
 relay_network_set_ssl_cert_key (int verbose)
 {
 #ifdef HAVE_GNUTLS
-    char *certkey_path, *certkey_path2;
+    char *certkey_path, *certkey_path2, *weechat_dir;
     int ret;
 
     gnutls_certificate_free_credentials (relay_gnutls_x509_cred);
@@ -63,9 +63,11 @@ relay_network_set_ssl_cert_key (int verbose)
     certkey_path = weechat_string_expand_home (weechat_config_string (relay_config_network_ssl_cert_key));
     if (certkey_path)
     {
+        weechat_dir = weechat_info_get ("weechat_dir", NULL);
         certkey_path2 = weechat_string_replace (certkey_path, "%h",
-                                                weechat_info_get ("weechat_dir",
-                                                                  NULL));
+                                                weechat_dir);
+        if (weechat_dir)
+            free (weechat_dir);
         if (certkey_path2)
         {
             ret = gnutls_certificate_set_x509_key_file (relay_gnutls_x509_cred,
diff --git a/src/plugins/relay/weechat/relay-weechat-protocol.c b/src/plugins/relay/weechat/relay-weechat-protocol.c
index 26509bc38..d007d6396 100644
--- a/src/plugins/relay/weechat/relay-weechat-protocol.c
+++ b/src/plugins/relay/weechat/relay-weechat-protocol.c
@@ -169,8 +169,7 @@ relay_weechat_protocol_is_sync (struct t_relay_client *ptr_client,
 
 RELAY_WEECHAT_PROTOCOL_CALLBACK(init)
 {
-    char **options, *pos, *password, *totp_secret, *info_totp_args;
-    const char *info_totp;
+    char **options, *pos, *password, *totp_secret, *info_totp_args, *info_totp;
     int i, compression, length;
 
     RELAY_WEECHAT_PROTOCOL_MIN_ARGS(1);
@@ -217,6 +216,8 @@ RELAY_WEECHAT_PROTOCOL_CALLBACK(init)
                             info_totp = weechat_info_get ("totp_validate", info_totp_args);
                             if (info_totp && (strcmp (info_totp, "1") == 0))
                                 RELAY_WEECHAT_DATA(client, totp_ok) = 1;
+                            if (info_totp)
+                                free (info_totp);
                             free (info_totp_args);
                         }
                         free (totp_secret);
@@ -290,7 +291,7 @@ RELAY_WEECHAT_PROTOCOL_CALLBACK(hdata)
 RELAY_WEECHAT_PROTOCOL_CALLBACK(info)
 {
     struct t_relay_weechat_msg *msg;
-    const char *info;
+    char *info;
 
     RELAY_WEECHAT_PROTOCOL_MIN_ARGS(1);
 
@@ -304,6 +305,8 @@ RELAY_WEECHAT_PROTOCOL_CALLBACK(info)
         relay_weechat_msg_add_string (msg, info);
         relay_weechat_msg_send (client, msg);
         relay_weechat_msg_free (msg);
+        if (info)
+            free (info);
     }
 
     return WEECHAT_RC_OK;
diff --git a/src/plugins/ruby/weechat-ruby-api.c b/src/plugins/ruby/weechat-ruby-api.c
index c5f0475d6..9d8207dee 100644
--- a/src/plugins/ruby/weechat-ruby-api.c
+++ b/src/plugins/ruby/weechat-ruby-api.c
@@ -57,8 +57,6 @@
     plugin_script_str2ptr (weechat_ruby_plugin,                         \
                            RUBY_CURRENT_SCRIPT_NAME,                    \
                            ruby_function_name, __string)
-#define API_STATIC_STRING(__string)                                     \
-    plugin_script_get_static_string(&ruby_data, __string);
 #define API_RETURN_OK return INT2FIX (1)
 #define API_RETURN_ERROR return INT2FIX (0)
 #define API_RETURN_EMPTY return Qnil
@@ -3598,14 +3596,14 @@ weechat_ruby_api_hook_modifier_exec (VALUE class, VALUE modifier,
     API_RETURN_STRING_FREE(result);
 }
 
-const char *
+char *
 weechat_ruby_api_hook_info_cb (const void *pointer, void *data,
                                const char *info_name,
                                const char *arguments)
 {
     struct t_plugin_script *script;
     void *func_argv[3];
-    char empty_arg[1] = { '\0' }, *result;
+    char empty_arg[1] = { '\0' };
     const char *ptr_function, *ptr_data;
 
     script = (struct t_plugin_script *)pointer;
@@ -3617,12 +3615,10 @@ weechat_ruby_api_hook_info_cb (const void *pointer, void *data,
         func_argv[1] = (info_name) ? (char *)info_name : empty_arg;
         func_argv[2] = (arguments) ? (char *)arguments : empty_arg;
 
-        result = (char *)weechat_ruby_exec (script,
-                                            WEECHAT_SCRIPT_EXEC_STRING,
-                                            ptr_function,
-                                            "sss", func_argv);
-
-        return API_STATIC_STRING(result);
+        return (char *)weechat_ruby_exec (script,
+                                          WEECHAT_SCRIPT_EXEC_STRING,
+                                          ptr_function,
+                                          "sss", func_argv);
     }
 
     return NULL;
@@ -5156,8 +5152,8 @@ weechat_ruby_api_command_options (VALUE class, VALUE buffer, VALUE command,
 static VALUE
 weechat_ruby_api_info_get (VALUE class, VALUE info_name, VALUE arguments)
 {
-    char *c_info_name, *c_arguments;
-    const char *result;
+    char *c_info_name, *c_arguments, *result;
+    VALUE return_value;
 
     API_INIT_FUNC(1, "info_get", API_RETURN_EMPTY);
     if (NIL_P (info_name) || NIL_P (arguments))
@@ -5171,7 +5167,7 @@ weechat_ruby_api_info_get (VALUE class, VALUE info_name, VALUE arguments)
 
     result = weechat_info_get (c_info_name, c_arguments);
 
-    API_RETURN_STRING(result);
+    API_RETURN_STRING_FREE(result);
 }
 
 static VALUE
diff --git a/src/plugins/ruby/weechat-ruby.c b/src/plugins/ruby/weechat-ruby.c
index 01feca504..d47a380b1 100644
--- a/src/plugins/ruby/weechat-ruby.c
+++ b/src/plugins/ruby/weechat-ruby.c
@@ -79,7 +79,6 @@ int ruby_eval_mode = 0;
 int ruby_eval_send_input = 0;
 int ruby_eval_exec_commands = 0;
 struct t_gui_buffer *ruby_eval_buffer = NULL;
-char *ruby_eval_output = NULL;
 #define RUBY_EVAL_SCRIPT                                                \
     "def weechat_init\n"                                                \
     "  Weechat.register('" WEECHAT_SCRIPT_EVAL_NAME "', '', '1.0', "    \
@@ -1111,23 +1110,23 @@ weechat_ruby_hdata_cb (const void *pointer, void *data,
  * Returns ruby info "ruby_eval".
  */
 
-const char *
+char *
 weechat_ruby_info_eval_cb (const void *pointer, void *data,
                            const char *info_name,
                            const char *arguments)
 {
+    char *output;
+
     /* make C compiler happy */
     (void) pointer;
     (void) data;
     (void) info_name;
 
     weechat_ruby_eval (NULL, 0, 0, (arguments) ? arguments : "");
-    if (ruby_eval_output)
-        free (ruby_eval_output);
-    ruby_eval_output = strdup (*ruby_buffer_output);
+    output = strdup (*ruby_buffer_output);
     weechat_string_dyn_copy (ruby_buffer_output, NULL);
 
-    return ruby_eval_output;
+    return output;
 }
 
 /*
@@ -1449,8 +1448,6 @@ weechat_plugin_end (struct t_weechat_plugin *plugin)
     if (ruby_action_autoload_list)
         free (ruby_action_autoload_list);
     weechat_string_dyn_free (ruby_buffer_output, 1);
-    if (ruby_eval_output)
-        free (ruby_eval_output);
 
     return WEECHAT_RC_OK;
 }
diff --git a/src/plugins/script/script-completion.c b/src/plugins/script/script-completion.c
index 50334713f..7878d7f80 100644
--- a/src/plugins/script/script-completion.c
+++ b/src/plugins/script/script-completion.c
@@ -189,8 +189,7 @@ script_completion_scripts_files_cb (const void *pointer, void *data,
                                     struct t_gui_buffer *buffer,
                                     struct t_gui_completion *completion)
 {
-    const char *weechat_home;
-    char *directory;
+    char *weechat_home, *directory;
     int length, i;
     void *pointers[2];
 
@@ -228,6 +227,9 @@ script_completion_scripts_files_cb (const void *pointer, void *data,
         free (directory);
     }
 
+    if (weechat_home)
+        free (weechat_home);
+
     return WEECHAT_RC_OK;
 }
 
diff --git a/src/plugins/script/script-config.c b/src/plugins/script/script-config.c
index 850255e8e..2006500f5 100644
--- a/src/plugins/script/script-config.c
+++ b/src/plugins/script/script-config.c
@@ -96,7 +96,8 @@ struct t_config_option *script_config_scripts_url;
 const char *
 script_config_get_diff_command ()
 {
-    const char *diff_command, *dir_separator;
+    const char *diff_command;
+    char *dir_separator;
     static char result[64];
     struct stat st;
     char *path, **paths, bin[4096];
@@ -135,6 +136,8 @@ script_config_get_diff_command ()
                 weechat_string_free_split (paths);
             }
         }
+        if (dir_separator)
+            free (dir_separator);
         if (!result[0])
             snprintf (result, sizeof (result), "diff");
         return result;
diff --git a/src/plugins/script/script-repo.c b/src/plugins/script/script-repo.c
index 833cd4f68..42dbd85f4 100644
--- a/src/plugins/script/script-repo.c
+++ b/src/plugins/script/script-repo.c
@@ -166,8 +166,7 @@ script_repo_search_by_name_ext (const char *name_with_extension)
 char *
 script_repo_get_filename_loaded (struct t_script_repo *script)
 {
-    const char *weechat_home;
-    char *filename, resolved_path[PATH_MAX];
+    char *weechat_home, *filename, resolved_path[PATH_MAX];
     int length;
     struct stat st;
 
@@ -175,7 +174,11 @@ script_repo_get_filename_loaded (struct t_script_repo *script)
     length = strlen (weechat_home) + strlen (script->name_with_extension) + 64;
     filename = malloc (length);
     if (!filename)
+    {
+        if (weechat_home)
+            free (weechat_home);
         return NULL;
+    }
 
     snprintf (filename, length, "%s/%s/autoload/%s",
               weechat_home,
@@ -193,6 +196,9 @@ script_repo_get_filename_loaded (struct t_script_repo *script)
         }
     }
 
+    if (weechat_home)
+        free (weechat_home);
+
     if (!filename[0])
     {
         free (filename);
@@ -801,8 +807,8 @@ script_repo_sha512sum_file (const char *filename)
 void
 script_repo_update_status (struct t_script_repo *script)
 {
-    const char *weechat_home, *version;
-    char *filename, *sha512sum;
+    const char *version;
+    char *weechat_home, *filename, *sha512sum;
     struct stat st;
     int length;
     struct t_script_repo *ptr_script;
@@ -841,6 +847,9 @@ script_repo_update_status (struct t_script_repo *script)
         free (filename);
     }
 
+    if (weechat_home)
+        free (weechat_home);
+
     /* check if script is held */
     if (script_repo_script_is_held (script))
         script->status |= SCRIPT_STATUS_HELD;
@@ -1140,8 +1149,8 @@ script_repo_file_read (int quiet)
 {
     char *filename, *ptr_line, line[4096], *pos, *pos2, *pos3;
     char *name, *value1, *value2, *value3, *value, *error;
-    char *locale, *locale_language;
-    const char *version, *ptr_locale, *ptr_desc;
+    char *info_locale, *locale, *locale_language, *version;
+    const char *ptr_desc;
     gzFile file;
     struct t_script_repo *script;
     int version_number, version_ok, script_ok, length;
@@ -1166,6 +1175,8 @@ script_repo_file_read (int quiet)
 
     version = weechat_info_get ("version", NULL);
     version_number = weechat_util_version_number (version);
+    if (version)
+        free (version);
 
     filename = script_config_get_xml_filename ();
     if (!filename)
@@ -1195,14 +1206,15 @@ script_repo_file_read (int quiet)
      */
     locale = NULL;
     locale_language = NULL;
-    ptr_locale = weechat_info_get ("locale", NULL);
-    if (ptr_locale)
+    info_locale = weechat_info_get ("locale", NULL);
+    if (info_locale)
     {
-        pos = strchr (ptr_locale, '.');
+        pos = strchr (info_locale, '.');
         if (pos)
-            locale = weechat_strndup (ptr_locale, pos - ptr_locale);
+            locale = weechat_strndup (info_locale, pos - info_locale);
         else
-            locale = strdup (ptr_locale);
+            locale = strdup (info_locale);
+        free (info_locale);
     }
     if (locale)
     {
@@ -1406,10 +1418,13 @@ script_repo_file_read (int quiet)
 
     if (scripts_repo && !quiet)
     {
+        version = weechat_info_get ("version", NULL);
         weechat_printf (NULL,
                         _("%s: %d scripts for WeeChat %s"),
                         SCRIPT_PLUGIN_NAME, script_repo_count,
-                        weechat_info_get ("version", NULL));
+                        version);
+        if (version)
+            free (version);
     }
 
     if (!scripts_repo)
diff --git a/src/plugins/spell/spell-info.c b/src/plugins/spell/spell-info.c
index 27024c09a..a92da0122 100644
--- a/src/plugins/spell/spell-info.c
+++ b/src/plugins/spell/spell-info.c
@@ -31,7 +31,7 @@
  * Returns spell info "spell_dict".
  */
 
-const char *
+char *
 spell_info_info_spell_dict_cb (const void *pointer, void *data,
                                const char *info_name,
                                const char *arguments)
@@ -39,13 +39,15 @@ spell_info_info_spell_dict_cb (const void *pointer, void *data,
     int rc;
     unsigned long value;
     struct t_gui_buffer *buffer;
-    const char *buffer_full_name;
+    const char *buffer_full_name, *ptr_dict;
 
     /* make C compiler happy */
     (void) pointer;
     (void) data;
     (void) info_name;
 
+    ptr_dict = NULL;
+
     if (!arguments)
         return NULL;
 
@@ -67,9 +69,9 @@ spell_info_info_spell_dict_cb (const void *pointer, void *data,
         buffer_full_name = arguments;
 
     if (buffer_full_name)
-        return spell_get_dict_with_buffer_name (buffer_full_name);
+        ptr_dict = spell_get_dict_with_buffer_name (buffer_full_name);
 
-    return NULL;
+    return (ptr_dict) ? strdup (ptr_dict) : NULL;
 }
 
 /*
diff --git a/src/plugins/tcl/weechat-tcl-api.c b/src/plugins/tcl/weechat-tcl-api.c
index 08b7e4f93..6609a0aea 100644
--- a/src/plugins/tcl/weechat-tcl-api.c
+++ b/src/plugins/tcl/weechat-tcl-api.c
@@ -68,8 +68,6 @@
     plugin_script_str2ptr (weechat_tcl_plugin,                          \
                            TCL_CURRENT_SCRIPT_NAME,                     \
                            tcl_function_name, __string)
-#define API_STATIC_STRING(__string)                                     \
-    plugin_script_get_static_string(&tcl_data, __string);
 #define API_RETURN_OK                                                   \
     {                                                                   \
         objp = Tcl_GetObjResult (interp);                               \
@@ -3284,14 +3282,14 @@ API_FUNC(hook_modifier_exec)
     API_RETURN_STRING_FREE(result);
 }
 
-const char *
+char *
 weechat_tcl_api_hook_info_cb (const void *pointer, void *data,
                               const char *info_name,
                                const char *arguments)
 {
     struct t_plugin_script *script;
     void *func_argv[3];
-    char empty_arg[1] = { '\0' }, *result;
+    char empty_arg[1] = { '\0' };
     const char *ptr_function, *ptr_data;
 
     script = (struct t_plugin_script *)pointer;
@@ -3303,12 +3301,10 @@ weechat_tcl_api_hook_info_cb (const void *pointer, void *data,
         func_argv[1] = (info_name) ? (char *)info_name : empty_arg;
         func_argv[2] = (arguments) ? (char *)arguments : empty_arg;
 
-        result = (char *)weechat_tcl_exec (script,
-                                           WEECHAT_SCRIPT_EXEC_STRING,
-                                           ptr_function,
-                                           "sss", func_argv);
-
-        return API_STATIC_STRING(result);
+        return (char *)weechat_tcl_exec (script,
+                                         WEECHAT_SCRIPT_EXEC_STRING,
+                                         ptr_function,
+                                         "sss", func_argv);
     }
 
     return NULL;
@@ -4631,7 +4627,7 @@ API_FUNC(command_options)
 API_FUNC(info_get)
 {
     Tcl_Obj *objp;
-    const char *result;
+    char *result;
     int i;
 
     API_INIT_FUNC(1, "info_get", API_RETURN_EMPTY);
@@ -4641,7 +4637,7 @@ API_FUNC(info_get)
     result = weechat_info_get (Tcl_GetStringFromObj (objv[1], &i),
                                Tcl_GetStringFromObj (objv[2], &i));
 
-    API_RETURN_STRING(result);
+    API_RETURN_STRING_FREE(result);
 }
 
 API_FUNC(info_get_hashtable)
diff --git a/src/plugins/tcl/weechat-tcl.c b/src/plugins/tcl/weechat-tcl.c
index 9bd7c3998..cd068a74e 100644
--- a/src/plugins/tcl/weechat-tcl.c
+++ b/src/plugins/tcl/weechat-tcl.c
@@ -57,7 +57,6 @@ int tcl_eval_mode = 0;
 int tcl_eval_send_input = 0;
 int tcl_eval_exec_commands = 0;
 struct t_gui_buffer *tcl_eval_buffer = NULL;
-char *tcl_eval_output = NULL;
 
 struct t_plugin_script *tcl_scripts = NULL;
 struct t_plugin_script *last_tcl_script = NULL;
@@ -760,12 +759,12 @@ weechat_tcl_hdata_cb (const void *pointer, void *data,
  * Returns tcl info "tcl_eval".
  */
 
-const char *
+char *
 weechat_tcl_info_eval_cb (const void *pointer, void *data,
                           const char *info_name,
                           const char *arguments)
 {
-    static const char *not_implemented = "not yet implemented";
+    const char *not_implemented = "not yet implemented";
 
     /* make C compiler happy */
     (void) pointer;
@@ -773,7 +772,7 @@ weechat_tcl_info_eval_cb (const void *pointer, void *data,
     (void) info_name;
     (void) arguments;
 
-    return not_implemented;
+    return strdup (not_implemented);
 }
 
 /*
@@ -984,8 +983,6 @@ weechat_plugin_end (struct t_weechat_plugin *plugin)
     if (tcl_action_autoload_list)
         free (tcl_action_autoload_list);
     /* weechat_string_dyn_free (tcl_buffer_output, 1); */
-    if (tcl_eval_output)
-        free (tcl_eval_output);
 
     return WEECHAT_RC_OK;
 }
diff --git a/src/plugins/weechat-plugin.h b/src/plugins/weechat-plugin.h
index e7bb8a921..4d9a61e39 100644
--- a/src/plugins/weechat-plugin.h
+++ b/src/plugins/weechat-plugin.h
@@ -806,10 +806,10 @@ struct t_weechat_plugin
                                  const char *info_name,
                                  const char *description,
                                  const char *args_description,
-                                 const char *(*callback)(const void *pointer,
-                                                         void *data,
-                                                         const char *info_name,
-                                                         const char *arguments),
+                                 char *(*callback)(const void *pointer,
+                                                   void *data,
+                                                   const char *info_name,
+                                                   const char *arguments),
                                  const void *callback_pointer,
                                  void *callback_data);
     struct t_hook *(*hook_info_hashtable) (struct t_weechat_plugin *plugin,
@@ -1003,9 +1003,8 @@ struct t_weechat_plugin
                                socklen_t address_length);
 
     /* infos */
-    const char *(*info_get) (struct t_weechat_plugin *plugin,
-                             const char *info_name,
-                             const char *arguments);
+    char *(*info_get) (struct t_weechat_plugin *plugin, const char *info_name,
+                       const char *arguments);
     struct t_hashtable *(*info_get_hashtable) (struct t_weechat_plugin *plugin,
                                                const char *info_name,
                                                struct t_hashtable *hashtable);
diff --git a/src/plugins/xfer/xfer-file.c b/src/plugins/xfer/xfer-file.c
index 8ab713842..ebed633f9 100644
--- a/src/plugins/xfer/xfer-file.c
+++ b/src/plugins/xfer/xfer-file.c
@@ -80,8 +80,7 @@ xfer_file_resume (struct t_xfer *xfer, const char *filename)
 void
 xfer_file_find_filename (struct t_xfer *xfer)
 {
-    const char *dir_separator;
-    char *path, *filename2;
+    char *dir_separator, *path, *filename2;
     int length;
 
     if (!XFER_IS_FILE(xfer->type))
@@ -106,7 +105,11 @@ xfer_file_find_filename (struct t_xfer *xfer)
     dir_separator = weechat_info_get ("dir_separator", "");
     if (dir_separator
         && (xfer->local_filename[strlen (xfer->local_filename) - 1] != dir_separator[0]))
+    {
         strcat (xfer->local_filename, dir_separator);
+    }
+    if (dir_separator)
+        free (dir_separator);
     if (weechat_config_boolean (xfer_config_file_use_nick_in_filename))
     {
         strcat (xfer->local_filename, xfer->remote_nick);
diff --git a/src/plugins/xfer/xfer.c b/src/plugins/xfer/xfer.c
index c186998fa..00b0a7a26 100644
--- a/src/plugins/xfer/xfer.c
+++ b/src/plugins/xfer/xfer.c
@@ -644,8 +644,8 @@ xfer_new (const char *plugin_name, const char *plugin_id,
           const char *local_filename)
 {
     struct t_xfer *new_xfer;
-    const char *ptr_color, *ptr_crc32;
-    char str_address[NI_MAXHOST];
+    const char *ptr_crc32;
+    char str_address[NI_MAXHOST], *color;
     int rc;
 
     new_xfer = xfer_alloc ();
@@ -669,8 +669,10 @@ xfer_new (const char *plugin_name, const char *plugin_id,
     new_xfer->type = type;
     new_xfer->protocol = protocol;
     new_xfer->remote_nick = strdup (remote_nick);
-    ptr_color = weechat_info_get ("irc_nick_color_name", remote_nick);
-    new_xfer->remote_nick_color = (ptr_color) ? strdup (ptr_color) : NULL;
+    color = weechat_info_get ("irc_nick_color_name", remote_nick);
+    new_xfer->remote_nick_color = (color) ? strdup (color) : NULL;
+    if (color)
+        free (color);
     new_xfer->local_nick = (local_nick) ? strdup (local_nick) : NULL;
     new_xfer->charset_modifier = (charset_modifier) ? strdup (charset_modifier) : NULL;
     if (XFER_IS_FILE(type))