--- Makefile.in.orig	2023-04-02 22:35:25 UTC
+++ Makefile.in
@@ -404,7 +404,8 @@ nobase_include_HEADERS = \
 libptexenc_la_LIBADD = $(KPATHSEA_LIBS)
 nobase_include_HEADERS = \
 	ptexenc/ptexenc.h \
-	ptexenc/unicode.h
+	ptexenc/unicode.h \
+	ptexenc/unicode-jp.h
 
 pkgconfigdir = $(prefix)/libdata/pkgconfig
 pkgconfig_DATA = ptexenc.pc