Everywhere: Fix -Winconsistent-missing-override warnings from Clang

This option is already enabled when building Lagom, so let's enable it
for the main build too. We will no longer be surprised by Lagom Clang
CI builds failing while everything compiles locally.

Furthermore, the stronger `-Wsuggest-override` warning is enabled in
this commit, which enforces the use of the `override` keyword in all
classes, not just those which already have some methods marked as
`override`. This works with both GCC and Clang.

9 files changed, 24 insertions, 24 deletions

diff --git a/Userland/Libraries/LibChess/UCICommand.h b/Userland/Libraries/LibChess/UCICommand.h
index e591906e5c..a72b78025c 100644
--- a/Userland/Libraries/LibChess/UCICommand.h
+++ b/Userland/Libraries/LibChess/UCICommand.h
@@ -58,7 +58,7 @@ public:
 
     static UCICommand from_string(StringView command);
 
-    virtual String to_string() const;
+    virtual String to_string() const override;
 };
 
 class DebugCommand : public Command {
@@ -76,7 +76,7 @@ public:
 
     static DebugCommand from_string(StringView command);
 
-    virtual String to_string() const;
+    virtual String to_string() const override;
 
     Flag flag() const { return m_flag; }
 
@@ -93,7 +93,7 @@ public:
 
     static IsReadyCommand from_string(StringView command);
 
-    virtual String to_string() const;
+    virtual String to_string() const override;
 };
 
 class SetOptionCommand : public Command {
@@ -107,7 +107,7 @@ public:
 
     static SetOptionCommand from_string(StringView command);
 
-    virtual String to_string() const;
+    virtual String to_string() const override;
 
     const String& name() const { return m_name; }
     const Optional<String>& value() const { return m_value; }
@@ -128,7 +128,7 @@ public:
 
     static PositionCommand from_string(StringView command);
 
-    virtual String to_string() const;
+    virtual String to_string() const override;
 
     const Optional<String>& fen() const { return m_fen; }
     const Vector<Chess::Move>& moves() const { return m_moves; }
@@ -147,7 +147,7 @@ public:
 
     static GoCommand from_string(StringView command);
 
-    virtual String to_string() const;
+    virtual String to_string() const override;
 
     Optional<Vector<Chess::Move>> searchmoves;
     bool ponder { false };
@@ -172,7 +172,7 @@ public:
 
     static StopCommand from_string(StringView command);
 
-    virtual String to_string() const;
+    virtual String to_string() const override;
 };
 
 class IdCommand : public Command {
@@ -191,7 +191,7 @@ public:
 
     static IdCommand from_string(StringView command);
 
-    virtual String to_string() const;
+    virtual String to_string() const override;
 
     Type field_type() const { return m_field_type; }
     const String& value() const { return m_value; }
@@ -210,7 +210,7 @@ public:
 
     static UCIOkCommand from_string(StringView command);
 
-    virtual String to_string() const;
+    virtual String to_string() const override;
 };
 
 class ReadyOkCommand : public Command {
@@ -222,7 +222,7 @@ public:
 
     static ReadyOkCommand from_string(StringView command);
 
-    virtual String to_string() const;
+    virtual String to_string() const override;
 };
 
 class BestMoveCommand : public Command {
@@ -235,7 +235,7 @@ public:
 
     static BestMoveCommand from_string(StringView command);
 
-    virtual String to_string() const;
+    virtual String to_string() const override;
 
     Chess::Move move() const { return m_move; }
 
@@ -252,7 +252,7 @@ public:
 
     static InfoCommand from_string(StringView command);
 
-    virtual String to_string() const;
+    virtual String to_string() const override;
 
     Optional<int> depth;
     Optional<int> seldepth;
diff --git a/Userland/Libraries/LibCrypto/Checksum/Adler32.h b/Userland/Libraries/LibCrypto/Checksum/Adler32.h
index 97117766ab..3c4595465b 100644
--- a/Userland/Libraries/LibCrypto/Checksum/Adler32.h
+++ b/Userland/Libraries/LibCrypto/Checksum/Adler32.h
@@ -27,8 +27,8 @@ public:
         update(data);
     }
 
-    void update(ReadonlyBytes data);
-    u32 digest();
+    virtual void update(ReadonlyBytes data) override;
+    virtual u32 digest() override;
 
 private:
     u32 m_state_a { 1 };
diff --git a/Userland/Libraries/LibCrypto/Checksum/CRC32.h b/Userland/Libraries/LibCrypto/Checksum/CRC32.h
index 885cf5bde5..e2913527fd 100644
--- a/Userland/Libraries/LibCrypto/Checksum/CRC32.h
+++ b/Userland/Libraries/LibCrypto/Checksum/CRC32.h
@@ -55,8 +55,8 @@ public:
         update(data);
     }
 
-    void update(ReadonlyBytes data);
-    u32 digest();
+    virtual void update(ReadonlyBytes data) override;
+    virtual u32 digest() override;
 
 private:
     u32 m_state { ~0u };
diff --git a/Userland/Libraries/LibJS/Heap/Heap.cpp b/Userland/Libraries/LibJS/Heap/Heap.cpp
index 023f0aaf7e..e616ecbb98 100644
--- a/Userland/Libraries/LibJS/Heap/Heap.cpp
+++ b/Userland/Libraries/LibJS/Heap/Heap.cpp
@@ -178,7 +178,7 @@ class MarkingVisitor final : public Cell::Visitor {
 public:
     MarkingVisitor() { }
 
-    virtual void visit_impl(Cell& cell)
+    virtual void visit_impl(Cell& cell) override
     {
         if (cell.is_marked())
             return;
diff --git a/Userland/Libraries/LibSQL/AST/AST.h b/Userland/Libraries/LibSQL/AST/AST.h
index b0ee4c7262..7dbcb7c389 100644
--- a/Userland/Libraries/LibSQL/AST/AST.h
+++ b/Userland/Libraries/LibSQL/AST/AST.h
@@ -943,7 +943,7 @@ public:
     bool has_selection() const { return !m_select_statement.is_null(); }
     const RefPtr<Select>& select_statement() const { return m_select_statement; }
 
-    RefPtr<SQLResult> execute(ExecutionContext&) const;
+    virtual RefPtr<SQLResult> execute(ExecutionContext&) const override;
 
 private:
     RefPtr<CommonTableExpressionList> m_common_table_expression_list;
diff --git a/Userland/Libraries/LibWeb/CSS/CSSImportRule.h b/Userland/Libraries/LibWeb/CSS/CSSImportRule.h
index 3958c54708..1c6e37a55c 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSImportRule.h
+++ b/Userland/Libraries/LibWeb/CSS/CSSImportRule.h
@@ -35,8 +35,8 @@ public:
     const RefPtr<CSSStyleSheet> loaded_style_sheet() const { return m_style_sheet; }
     void set_style_sheet(const RefPtr<CSSStyleSheet>& style_sheet) { m_style_sheet = style_sheet; }
 
-    virtual StringView class_name() const { return "CSSImportRule"; };
-    virtual Type type() const { return Type::Import; };
+    virtual StringView class_name() const override { return "CSSImportRule"; };
+    virtual Type type() const override { return Type::Import; };
 
 private:
     explicit CSSImportRule(AK::URL, DOM::Document&);
diff --git a/Userland/Libraries/LibWeb/CSS/StyleValue.h b/Userland/Libraries/LibWeb/CSS/StyleValue.h
index 14f52b4a2f..7ddc949809 100644
--- a/Userland/Libraries/LibWeb/CSS/StyleValue.h
+++ b/Userland/Libraries/LibWeb/CSS/StyleValue.h
@@ -1345,7 +1345,7 @@ public:
         return m_values[i];
     }
 
-    virtual String to_string() const
+    virtual String to_string() const override
     {
         StringBuilder builder;
         builder.appendff("List[{}](", m_values.size());
diff --git a/Userland/Libraries/LibWeb/DOM/Document.h b/Userland/Libraries/LibWeb/DOM/Document.h
index 9f374ec385..c1d93e3bdf 100644
--- a/Userland/Libraries/LibWeb/DOM/Document.h
+++ b/Userland/Libraries/LibWeb/DOM/Document.h
@@ -171,7 +171,7 @@ public:
     const String& source() const { return m_source; }
     void set_source(const String& source) { m_source = source; }
 
-    JS::Realm& realm();
+    virtual JS::Realm& realm() override;
     JS::Interpreter& interpreter();
 
     JS::Value run_javascript(StringView source, StringView filename = "(unknown)");
diff --git a/Userland/Libraries/LibWeb/Layout/Box.h b/Userland/Libraries/LibWeb/Layout/Box.h
index d256ecbc73..71f2e65d85 100644
--- a/Userland/Libraries/LibWeb/Layout/Box.h
+++ b/Userland/Libraries/LibWeb/Layout/Box.h
@@ -161,8 +161,8 @@ public:
 
     void clear_overflow_data() { m_overflow_data = nullptr; }
 
-    virtual void before_children_paint(PaintContext&, PaintPhase);
-    virtual void after_children_paint(PaintContext&, PaintPhase);
+    virtual void before_children_paint(PaintContext&, PaintPhase) override;
+    virtual void after_children_paint(PaintContext&, PaintPhase) override;
 
 protected:
     Box(DOM::Document& document, DOM::Node* node, NonnullRefPtr<CSS::StyleProperties> style)