[babl] meson build: try to add -Ofast to CFLAGS

[Øyvind "pippin" Kolås <ok src gnome org>]

commit 2813752584558a32a321a57cc87150ba72ff5841
Author: John Marshall <jtm home gmail com>
Date:   Mon Jun 11 09:27:33 2018 +0100

    meson build: try to add -Ofast to CFLAGS

 meson.build | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)
---
diff --git a/meson.build b/meson.build
index 95270b4..fbca825 100644
--- a/meson.build
+++ b/meson.build
@@ -137,7 +137,12 @@ build_platform_win32 = (build_os.startswith('mingw') or
 
 
 ################################################################################
-# Extra warnings
+# Compiler arguments
+
+common_c_flags = []
+if cc.get_id().startswith('clang') or cc.get_id().startswith('gcc')
+  common_c_flags += cc.get_supported_arguments(['-Ofast'])
+endif
 
 extra_warnings_list = [
   '-Wdeclaration-after-statement',
@@ -147,13 +152,9 @@ extra_warnings_list = [
   '-Wold-style-definition',
   '-Wpointer-arith',
 ]
-extra_warnings = []
-foreach warning : extra_warnings_list
-  if cc.has_argument(warning)
-    extra_warnings += warning
-  endif
-endforeach
+common_c_flags += cc.get_supported_arguments(extra_warnings_list)
 
+add_project_arguments(common_c_flags, language: 'c')
 
 ################################################################################
 # Check for compiler CPU extensions