Merge pull request #658 from t-b/fix-snprintf-detection

[Backport] log4tango: Fix snprintf test

Author: t-b

log4tango/m4/AC_FUNC_SNPRINTF.m4

@@ -13,6 +13,7 @@ dnl
 AC_DEFUN([AC_FUNC_SNPRINTF],
 [AC_CACHE_CHECK(for working snprintf, ac_cv_func_snprintf,
 [AC_TRY_RUN([#include <stdio.h>
+#include <stdlib.h> // exit
 int main () { int l = snprintf(NULL,0,"%d",100); exit (!((3 <= l) || (-1 == l))); }
 ], ac_cv_func_snprintf=yes, ac_cv_func_snprintf=no,
 ac_cv_func_snprintf=no)])