From: Sevan Janiyan <venture37@geeklan.co.uk>
Date: Tue, 5 Jan 2016 11:43:17 +0000 (+0000)
Subject: Use a macro to indicate C99 to the compiler
X-Git-Tag: json-c-0.13-20171207~169^2
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=7150b7f28d32435955391780ca9df7715bbfeda7;p=json-c

Use a macro to indicate C99 to the compiler

The [AC_PROG_CC_C99 macro](https://www.gnu.org/software/autoconf/manual/autoconf-2.64/html_node/C-Compiler.html) sets the complier to the C99 standard if the compiler does not default to such behaviour (albeit gnu99). This is better than specifically hardcoding flags
---

diff --git a/configure.ac b/configure.ac
index 2f3c92f..7d43cad 100644
--- a/configure.ac
+++ b/configure.ac
@@ -30,6 +30,7 @@ m4_ifdef([AM_SILENT_RULES], [AM_SILENT_RULES([yes])])
 
 # Checks for header files.
 AM_PROG_CC_C_O
+AC_PROG_CC_C99
 AC_CONFIG_HEADER(config.h)
 AC_CONFIG_HEADER(json_config.h)
 AC_HEADER_STDC
@@ -104,7 +105,6 @@ AC_SUBST(JSON_BSYMBOLIC_LDFLAGS)
 
 AX_APPEND_COMPILE_FLAGS([-Wall -Werror -Wno-error=deprecated-declarations])
 AX_APPEND_COMPILE_FLAGS([-Wextra -Wwrite-string -Wno-unused-parameter])
-AX_APPEND_COMPILE_FLAGS([-std=gnu99])
 AX_APPEND_COMPILE_FLAGS([-D_GNU_SOURCE -D_REENTRANT])
 
 AC_CONFIG_FILES([