extern-inline: make safe for -Wundef usage

[gnulib.git] / m4 / extern-inline.m4

diff --git a/m4/extern-inline.m4 b/m4/extern-inline.m4
index 4862d60..e4454d8 100644 (file)
--- a/m4/extern-inline.m4
+++ b/m4/extern-inline.m4
@@ -1,3 +1,4 @@
+# extern-inline.m4 serial 2
 dnl 'extern inline' a la ISO C99.
 
 dnl Copyright 2012-2013 Free Software Foundation, Inc.
@@ -41,7 +42,7 @@ AC_DEFUN([gl_EXTERN_INLINE],
 # define _GL_EXTERN_INLINE_IN_USE
 #elif (2 < __GNUC__ + (7 <= __GNUC_MINOR__) && !defined __STRICT_ANSI__ \
        && !defined _GL_EXTERN_INLINE_APPLE_BUG)
-# if __GNUC_GNU_INLINE__
+# if defined __GNUC_GNU_INLINE__ && __GNUC_GNU_INLINE__
    /* __gnu_inline__ suppresses a GCC 4.2 diagnostic.  */
 #  define _GL_INLINE extern inline __attribute__ ((__gnu_inline__))
 # else