[SCM] libav/experimental: Check for __attribute__((packed)) support

[siretart at users.alioth.debian.org]

The following commit has been merged in the experimental branch:
commit e7ea5e3d8d60b92467b653b91daf47146b49b53f
Author: Måns Rullgård <mans at mansr.com>
Date:   Fri Jul 17 08:21:43 2009 +0000

    Check for __attribute__((packed)) support
    
    Not all compilers claiming to be gcc support this attribute.
    
    Originally committed as revision 19453 to svn://svn.ffmpeg.org/ffmpeg/trunk

diff --git a/configure b/configure
index 435f9f4..9a614a5 100755
--- a/configure
+++ b/configure
@@ -899,6 +899,7 @@ HAVE_LIST="
     alsa_asoundlib_h
     altivec_h
     arpa_inet_h
+    attribute_packed
     bigendian
     bswap
     closesocket
@@ -2165,6 +2166,10 @@ void foo(char * $restrict_keyword p);
 EOF
 done
 
+check_cc <<EOF && enable attribute_packed
+struct { int x; } __attribute__((packed)) x;
+EOF
+
 ##########################################
 # SDL check
 
diff --git a/libavutil/intreadwrite.h b/libavutil/intreadwrite.h
index ee59793..d46595e 100644
--- a/libavutil/intreadwrite.h
+++ b/libavutil/intreadwrite.h
@@ -42,7 +42,7 @@
  * by per-arch headers.
  */
 
-#if   defined(__GNUC__)
+#if   HAVE_ATTRIBUTE_PACKED
 
 struct unaligned_64 { uint64_t l; } __attribute__((packed));
 struct unaligned_32 { uint32_t l; } __attribute__((packed));

-- 
Libav/FFmpeg packaging