Re: [PATCH] Attempt to increase RLIMIT_STACK in the driver as well as compiler (PR c++/49756, take 2)

[Richard Guenther <richard dot guenther at gmail dot com>]

On Tue, Jul 19, 2011 at 10:24 AM, Jakub Jelinek <jakub@redhat.com> wrote:
> On Mon, Jul 18, 2011 at 11:58:38PM +0200, Jakub Jelinek wrote:
>> Especially the FEs and gimplification are highly recursive on more complex
>> (especially badly generated) testcases, the following patch attempts to
>> increase stack size to 64MB if possible. ?It is done in the driver
>> (where it can affect the children of the driver early) and also in
>> toplev_main to make similar results when invoking the compiler by hand,
>> unless mmap of some shared library or some other mmap make it impossible
>> to have such a large stack.
>>
>> Bootstrapped/regtested on x86_64-linux and i686-linux, cures
>> gcc.c-torture/compile/limits-exprparen.c ICEs on x86_64-linux on all
>> -O* levels as well as the testcase from this PR (which is quite large and
>> compile time consuming, so not including it in this testcase).
>
> Here is a slightly modified variant which will avoid the setrlimit syscall
> if it wouldn't change anything (which is either if the soft limit is already
>>= 64MB or the hard limit is not infinity and equal to the soft limit).
> At least in toplev_main it is very likely the setrlimit will not be needed
> if it has been done in the driver already.

Looks like sth for libiberty to avoid replicating it two times?

Richard.

> 2011-07-19 ?Jakub Jelinek ?<jakub@redhat.com>
>
> ? ? ? ?PR c++/49756
> ? ? ? ?* gcc.c (main): Try to increase RLIMIT_STACK to at least
> ? ? ? ?64MB if possible.
> ? ? ? ?* toplev.c (toplev_main): Likewise.
>
> --- gcc/gcc.c.jj ? ? ? ?2011-07-08 15:09:38.000000000 +0200
> +++ gcc/gcc.c ? 2011-07-19 10:15:25.000000000 +0200
> @@ -6156,6 +6156,24 @@ main (int argc, char **argv)
> ? signal (SIGCHLD, SIG_DFL);
> ?#endif
>
> +#if defined(HAVE_SETRLIMIT) && defined(RLIMIT_STACK) && defined(RLIM_INFINITY)
> + ?{
> + ? ?/* Parsing and gimplification sometimes need quite large stack.
> + ? ? ? Increase stack size limits if possible. ?*/
> + ? ?struct rlimit rlim;
> + ? ?if (getrlimit (RLIMIT_STACK, &rlim) == 0
> + ? ? ? && rlim.rlim_cur != RLIM_INFINITY
> + ? ? ? && rlim.rlim_cur < 64 * 1024 * 1024
> + ? ? ? && (rlim.rlim_max == RLIM_INFINITY || rlim.rlim_cur < rlim.rlim_max))
> + ? ? ?{
> + ? ? ? rlim.rlim_cur = 64 * 1024 * 1024;
> + ? ? ? if (rlim.rlim_max != RLIM_INFINITY)
> + ? ? ? ? rlim.rlim_cur = MIN (rlim.rlim_cur, rlim.rlim_max);
> + ? ? ? setrlimit (RLIMIT_STACK, &rlim);
> + ? ? ?}
> + ?}
> +#endif
> +
> ? /* Allocate the argument vector. ?*/
> ? alloc_args ();
>
> --- gcc/toplev.c.jj ? ? 2011-07-11 10:39:50.000000000 +0200
> +++ gcc/toplev.c ? ? ? ?2011-07-19 10:15:37.000000000 +0200
> @@ -1911,6 +1911,24 @@ do_compile (void)
> ?int
> ?toplev_main (int argc, char **argv)
> ?{
> +#if defined(HAVE_SETRLIMIT) && defined(RLIMIT_STACK) && defined(RLIM_INFINITY)
> + ?{
> + ? ?/* Parsing and gimplification sometimes need quite large stack.
> + ? ? ? Increase stack size limits if possible. ?*/
> + ? ?struct rlimit rlim;
> + ? ?if (getrlimit (RLIMIT_STACK, &rlim) == 0
> + ? ? ? && rlim.rlim_cur != RLIM_INFINITY
> + ? ? ? && rlim.rlim_cur < 64 * 1024 * 1024
> + ? ? ? && (rlim.rlim_max == RLIM_INFINITY || rlim.rlim_cur < rlim.rlim_max))
> + ? ? ?{
> + ? ? ? rlim.rlim_cur = 64 * 1024 * 1024;
> + ? ? ? if (rlim.rlim_max != RLIM_INFINITY)
> + ? ? ? ? rlim.rlim_cur = MIN (rlim.rlim_cur, rlim.rlim_max);
> + ? ? ? setrlimit (RLIMIT_STACK, &rlim);
> + ? ? ?}
> + ?}
> +#endif
> +
> ? expandargv (&argc, &argv);
>
> ? /* Initialization of GCC's environment, and diagnostics. ?*/
>
> ? ? ? ?Jakub
>