* vm.c (th_init): preallocate alternative stack.

  NoMemoryError is better than rb_bug, of course.
  Patch by Eric Wong. [ruby-core:38572][ruby-core:38594].

* signal.c (rb_register_sigaltstack): ditto.

* vm_core.h: moved ALT_STACK_SIZE definition from signal.c.
* vm.c (thread_free): use xfree() instead of free().



git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@32749 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 4 insertions, 11 deletions

diff --git a/signal.c b/signal.c
index 3d9a1dbde5..02ec9d3ebc 100644
--- a/signal.c
+++ b/signal.c
@@ -423,29 +423,22 @@ typedef RETSIGTYPE ruby_sigaction_t(int);
 #ifdef POSIX_SIGNAL
 
 #ifdef USE_SIGALTSTACK
-#ifdef SIGSTKSZ
-#define ALT_STACK_SIZE (SIGSTKSZ*2)
-#else
-#define ALT_STACK_SIZE (4*1024)
-#endif
 /* alternate stack for SIGSEGV */
 void
 rb_register_sigaltstack(rb_thread_t *th)
 {
     stack_t newSS, oldSS;
 
-    if (th->altstack) return;
+    if (!th->altstack)
+	rb_bug("rb_register_sigaltstack: th->altstack not initialized\n");
 
-    newSS.ss_sp = th->altstack = malloc(ALT_STACK_SIZE);
-    if (newSS.ss_sp == NULL)
-	/* should handle error */
-	rb_bug("rb_register_sigaltstack. malloc error\n");
+    newSS.ss_sp = th->altstack;
     newSS.ss_size = ALT_STACK_SIZE;
     newSS.ss_flags = 0;
 
     sigaltstack(&newSS, &oldSS); /* ignore error. */
 }
-#endif
+#endif /* USE_SIGALTSTACK */
 
 static sighandler_t
 ruby_signal(int signum, sighandler_t handler)