From 60ec2d48786c3c34af8f44bb9f7441df44b0b4dd Mon Sep 17 00:00:00 2001
From: Marvin Scholz <epirat07@gmail.com>
Date: Sat, 16 Jun 2018 17:12:34 +0200
Subject: [PATCH] Add -std=c99 arg to compiler if possible

---
 configure.ac | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/configure.ac b/configure.ac
index ff677984..02883e14 100644
--- a/configure.ac
+++ b/configure.ac
@@ -7,6 +7,13 @@ AC_CONFIG_MACRO_DIR([m4])
 AC_CONFIG_AUX_DIR([build-aux])
 
 AC_PROG_CC
+
+AX_CHECK_COMPILE_FLAG([-std=c99], [
+  AX_APPEND_FLAG([-std=c99])
+], [
+  AC_MSG_WARN([Compiler does not accept -std=c99 flag!])
+])
+
 AC_PROG_CC_C99
 
 AS_IF([test "${ac_cv_prog_cc_c99}" = "no"], [