diff --git a/gcc/cp/cfns.gperf b/gcc/cp/cfns.gperf
index 68acd3d..953262f 100644
--- a/gcc/cp/cfns.gperf
+++ b/gcc/cp/cfns.gperf
@@ -22,6 +22,9 @@ __inline
 static unsigned int hash (const char *, unsigned int);
 #ifdef __GNUC__
 __inline
+#ifdef __GNUC_STDC_INLINE__
+__attribute__ ((__gnu_inline__))
+#endif
 #endif
 const char * libc_name_p (const char *, unsigned int);
 %}
diff --git a/gcc/cp/cfns.h b/gcc/cp/cfns.h
index 1c6665d..6d00c0e 100644
--- a/gcc/cp/cfns.h
+++ b/gcc/cp/cfns.h
@@ -53,6 +53,9 @@ __inline
 static unsigned int hash (const char *, unsigned int);
 #ifdef __GNUC__
 __inline
+#ifdef __GNUC_STDC_INLINE__
+__attribute__ ((__gnu_inline__))
+#endif
 #endif
 const char * libc_name_p (const char *, unsigned int);
 /* maximum key range = 391, duplicates = 0 */