Bug 4001

tree/branch: poky/master
commit d823759b4594143d522eae0b2a2498436a6dcb1e

Test Env:
SUSE Linux Enterprise Desktop 11 SP2  (i586) 
Linux version 3.0.13-0.27-pae (geeko@buildhost) 
(gcc version 4.3.4 [gcc-4_3-branch revision 152973] (SUSE Linux) ) 

*problem
when build qemu-native on SLED 11.2, there is an error:
...
| In file included from /usr/include/bits/sigcontext.h:28,
|    from /usr/include/signal.h:339,
|    from /buildarea2/tmp/work/i686-linux/qemu-native/1.4.0-r0/
qemu-1.4.0/include/qemu-common.h:42,
|    from fsdev/virtfs-proxy-helper.c:23:
| /usr/include/asm/sigcontext.h:28: error: expected specifier-
qualifier-list before '__u64'
| /usr/include/asm/sigcontext.h:191: error: expected specifier-
qualifier-list before '__u64'
...

*analysis
1, In the following header include map, `-->' presents `include':
...
"virtfs-proxy-helper.c" --> <sys/capability.h>
...
"virtfs-proxy-helper.c" --> "qemu-common.h" --> <signal.h> -->
<bits/sigcontext.h> --> <asm/sigcontext.h> --> <linux/types.h> -->
<asm/types.h> --> <asm-generic/types.h> --> <asm-generic/int-ll64.h>
...
and '__u64' is defined in <asm-generic/int-ll64.h>.

2, The bug is found on SLED 11.2 x86. In libcap header file
/usr/include/sys/capability.h, it does evil stuff like this:
...
  25 /*
  26  * Make sure we can be included from userland by preventing
  27  * capability.h from including other kernel headers
  28  */
  29 #define _LINUX_TYPES_H
  30 #define _LINUX_FS_H
  31 #define __LINUX_COMPILER_H
  32 #define __user
  33
  34 typedef unsigned int __u32;
  35 typedef __u32 __le32;
...
This completely prevents including /usr/include/linux/types.h, etc.
The above `<asm/sigcontext.h> --> <linux/types.h>' is prevented.

*resolution
Modify virtfs-proxy-helper.c to include <sys/capability.h> last
to workaround the issue.

http://www.linuxtv.org/pipermail/vdr/2009-August/021194.html
http://patchwork.linuxtv.org/patch/12748/