diff --git a/src/stdafx.h b/src/stdafx.h
index 6a33223455..19009f5ff5 100644
--- a/src/stdafx.h
+++ b/src/stdafx.h
@@ -138,6 +138,12 @@
 #	endif
 #endif /* __GNUC__ || __clang__ */
 
+#if __GNUC__ > 11 || (__GNUC__ == 11 && __GNUC_MINOR__ >= 1)
+#      define NOACCESS(args) __attribute__ ((access (none, args)))
+#else
+#      define NOACCESS(args)
+#endif
+
 #if defined(__WATCOMC__)
 #	define NORETURN
 #	define CDECL
diff --git a/src/string_func.h b/src/string_func.h
index 6c894b3cba..4fe9d7b825 100644
--- a/src/string_func.h
+++ b/src/string_func.h
@@ -30,25 +30,25 @@
 #include "core/bitmath_func.hpp"
 #include "string_type.h"
 
-char *strecat(char *dst, const char *src, const char *last);
-char *strecpy(char *dst, const char *src, const char *last);
-char *stredup(const char *src, const char *last = nullptr);
+char *strecat(char *dst, const char *src, const char *last) NOACCESS(3);
+char *strecpy(char *dst, const char *src, const char *last) NOACCESS(3);
+char *stredup(const char *src, const char *last = nullptr) NOACCESS(2);
 
-int CDECL seprintf(char *str, const char *last, const char *format, ...) WARN_FORMAT(3, 4);
-int CDECL vseprintf(char *str, const char *last, const char *format, va_list ap) WARN_FORMAT(3, 0);
+int CDECL seprintf(char *str, const char *last, const char *format, ...) WARN_FORMAT(3, 4) NOACCESS(2);
+int CDECL vseprintf(char *str, const char *last, const char *format, va_list ap) WARN_FORMAT(3, 0) NOACCESS(2);
 
 char *CDECL str_fmt(const char *str, ...) WARN_FORMAT(1, 2);
 
-void str_validate(char *str, const char *last, StringValidationSettings settings = SVS_REPLACE_WITH_QUESTION_MARK);
+void str_validate(char *str, const char *last, StringValidationSettings settings = SVS_REPLACE_WITH_QUESTION_MARK) NOACCESS(2);
 std::string str_validate(const std::string &str, StringValidationSettings settings = SVS_REPLACE_WITH_QUESTION_MARK);
 void ValidateString(const char *str);
 
-void str_fix_scc_encoded(char *str, const char *last);
+void str_fix_scc_encoded(char *str, const char *last) NOACCESS(2);
 void str_strip_colours(char *str);
 bool strtolower(char *str);
 bool strtolower(std::string &str, std::string::size_type offs = 0);
 
-bool StrValid(const char *str, const char *last);
+bool StrValid(const char *str, const char *last) NOACCESS(2);
 void StrTrimInPlace(char *str);
 
 /**