diff --git a/common.mk b/common.mk
index badd52e872..c64f734c11 100644
--- a/common.mk
+++ b/common.mk
@@ -11138,6 +11138,7 @@ parse.$(OBJEXT): {$(VPATH)}parse.c
 parse.$(OBJEXT): {$(VPATH)}parse.h
 parse.$(OBJEXT): {$(VPATH)}parse.y
 parse.$(OBJEXT): {$(VPATH)}parser_node.h
+parse.$(OBJEXT): {$(VPATH)}parser_st.h
 parse.$(OBJEXT): {$(VPATH)}probes.dmyh
 parse.$(OBJEXT): {$(VPATH)}probes.h
 parse.$(OBJEXT): {$(VPATH)}ractor.h
diff --git a/ext/ripper/depend b/ext/ripper/depend
index 79a9693352..e8582f5c66 100644
--- a/ext/ripper/depend
+++ b/ext/ripper/depend
@@ -603,6 +603,7 @@ ripper.o: $(top_srcdir)/internal/warnings.h
 ripper.o: $(top_srcdir)/method.h
 ripper.o: $(top_srcdir)/node.h
 ripper.o: $(top_srcdir)/parser_node.h
+ripper.o: $(top_srcdir)/parser_st.h
 ripper.o: $(top_srcdir)/regenc.h
 ripper.o: $(top_srcdir)/ruby_assert.h
 ripper.o: $(top_srcdir)/ruby_atomic.h
diff --git a/parse.y b/parse.y
index f17002a311..63147c7fb4 100644
--- a/parse.y
+++ b/parse.y
@@ -276,11 +276,13 @@ parse_isxdigit(int c)
 #undef ISXDIGIT
 #define ISXDIGIT(c) parse_isxdigit(c)
 
+#include "parser_st.h"
+
 #undef STRCASECMP
-#define STRCASECMP st_locale_insensitive_strcasecmp
+#define STRCASECMP rb_parser_st_locale_insensitive_strcasecmp
 
 #undef STRNCASECMP
-#define STRNCASECMP st_locale_insensitive_strncasecmp
+#define STRNCASECMP rb_parser_st_locale_insensitive_strncasecmp
 
 #ifdef RIPPER
 #include "ripper_init.h"