From: Christian Brauner <christian.brauner@ubuntu.com>
Date: Wed, 29 Sep 2021 08:02:39 +0000 (+0200)
Subject: build: compiler attribute improvements
X-Git-Tag: lxc-5.0.0~82^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=refs%2Fpull%2F3983%2Fhead;p=thirdparty%2Flxc.git

build: compiler attribute improvements

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---

diff --git a/meson.build b/meson.build
index e37c4694b..d832eb8b3 100644
--- a/meson.build
+++ b/meson.build
@@ -355,8 +355,13 @@ conf.set10('HAVE_STRCHRNUL', have)
 have = cc.has_function('openpty', prefix : '#include <pty.h>', args : '-D_GNU_SOURCE')
 conf.set10('HAVE_OPENPTY', have)
 
-conf.set10('HAVE_COMPILER_ATTR_NONNULL', cc.has_function_attribute('nonnull'))
-conf.set10('HAVE_COMPILER_ATTR_RETURNS_NONNULL', cc.has_function_attribute('returns_nonnull'))
+foreach ccattr : ['fallthrough',
+		  'nonnull',
+		  'returns_nonnull',
+		 ]
+
+        conf.set10('HAVE_COMPILER_ATTR_' + ccattr.underscorify().to_upper(), cc.has_function_attribute(ccattr))
+endforeach
 
 config_h = configure_file(
         output : 'config.h',
diff --git a/src/lxc/compiler.h b/src/lxc/compiler.h
index ec071dc83..4d6232382 100644
--- a/src/lxc/compiler.h
+++ b/src/lxc/compiler.h
@@ -18,7 +18,7 @@
 #endif
 #endif
 
-#if __GNUC__ >= 7
+#if HAVE_COMPILER_ATTR_FALLTHROUGH || __GNUC__ >= 7
 #define __fallthrough __attribute__((__fallthrough__))
 #else
 #define __fallthrough /* fall through */