stack ws workspace for pcre and others #1576

[Poul-Henning Kamp]

--------
In message <CAJV_h0ZfT-BwxxLf-ddz1Lb5C+W0SKvFNkKQS79CDMM9ANdnWA at mail.gmail.com>
, Federico Schwindt writes:

+#ifdef HAVE_SIGALTSTACK
+       if (cache_param->sigsegv_handler) {
+               char stackbuf[MINSIGSTKSZ];
+               stack_t ss;
+
+               ss.ss_size = sizeof(stackbuf);
+               ss.ss_sp = stackbuf;
+               ss.ss_flags = 0;
+               (void)sigaltstack(&ss, NULL);
+       }
+#endif

This will ad 2-4 KB to all threads.

Also, I'm not convinced about the wisdom of allocating the sigstack
on the normal stack...

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk at FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.