[RFC PATCH] Use anonymous union for siginfo_t

[Zack Weinberg]

On Fri, Aug 11, 2017 at 12:48 PM, Paul Eggert <eggert@cs.ucla.edu> wrote:
> On 08/11/2017 07:02 AM, Zack Weinberg wrote:
>>
>> The catch, however, is that the compiler
>> used to compile*programs that use glibc*  - not just glibc itself -
>> must accept the use of this feature (in system headers) even when
>> running in an older conformance mode.
>
>
> Perhaps you could survey other non-GCC compilers in use with glibc, as to
> whether they support this feature. Not just Clang, but also ARM, Cray CCE,
> Fujitsu/Lahey, IBM XL C/C++, Intel, PGI, Oracle Studio, and maybe PathScale.

This is a fine idea but I don't know that I can get my hands on all of
these compilers, certainly not this week or next week (family-related
travel).  Perhaps people who already have them could give it a try?
This test program should be sufficient...

#define _XOPEN_SOURCE 600
#include <signal.h>

extern void do_something(int);

void
handler(int sig, siginfo_t *info, void *ctx)
{
   do_something(info->si_value.sival_int);
}

compiled with the equivalent of -c -std=c99 and the warnings cranked
up as high as they will go.  I'll push my branch when I get home.

zw