1 files changed, 7 insertions, 2 deletions
diff --git a/source3/configure.in b/source3/configure.in
index e65d89ef4b..3083901f72 100644
--- a/source3/configure.in
+++ b/source3/configure.in
@@ -812,11 +812,16 @@ AC_TRY_RUN([
 void foo(const char *format, ...) { 
        va_list ap;
        int len;
+       char buf[5];
+
        va_start(ap, format);
        len = vsnprintf(0, 0, format, ap);
        va_end(ap);
-       if (len == 5) exit(0);
-       exit(1);
+       if (len != 5) exit(1);
+
+       if (snprintf(buf, 3, "hello") != 5 || strcmp(buf, "he") != 0) exit(1);
+
+       exit(0);
 }
 main() { foo("hello"); }
 ],