(AC_C_PROTOTYPES): Define __PROTOTYPES too.

diff --git a/lib/autoconf/c.m4 b/lib/autoconf/c.m4
index 7662c071c9fe8ca5e81635e42ef58d29cb7eebf1..0ba0d67338dfdc81cacc57ee94504b5b4ce9a1b1 100644 (file)
--- a/lib/autoconf/c.m4
+++ b/lib/autoconf/c.m4
@@ -1068,6 +1068,8 @@ if test "$ac_cv_prog_cc_stdc" != no; then
   AC_MSG_RESULT([yes])
   AC_DEFINE(PROTOTYPES, 1,
             [Define to 1 if the C compiler supports function prototypes.])
+  AC_DEFINE(__PROTOTYPES, 1,
+            [Define like PROTOTYPES; this can be used by system headers.])
 else
   AC_MSG_RESULT([no])
 fi