--- gforth/engine/signals.c	2011/11/16 01:25:58	1.41
+++ gforth/engine/signals.c	2012/03/23 22:39:00	1.48
@@ -1,6 +1,6 @@
 /* signal handling
 
-  Copyright (C) 1995,1996,1997,1998,2000,2003,2006,2007 Free Software Foundation, Inc.
+  Copyright (C) 1995,1996,1997,1998,2000,2003,2006,2007,2011 Free Software Foundation, Inc.
 
   This file is part of Gforth.
 
@@ -34,6 +34,15 @@
 #include <termios.h>
 #include "io.h"
 
+#ifdef HAS_DEBUG
+extern int debug;
+# define debugp(x...) do { if (debug) fprintf(x); } while (0)
+#else
+# define perror(x...)
+# define fprintf(x...)
+# define debugp(x...)
+#endif
+
 #ifndef HAVE_STACK_T
 /* Darwin uses "struct sigaltstack" instead of "stack_t" */
 typedef struct sigaltstack stack_t;
@@ -92,17 +101,19 @@ graceful_exit (int sig)
   exit (0x80|sig);
 }
 
-jmp_buf throw_jmp_buf;
+__thread jmp_buf * throw_jmp_handler;
 
 void throw(int code)
 {
-  longjmp(throw_jmp_buf,code); /* !! or use siglongjmp ? */
+  debugp(stderr,"\nthrow code %d to %p\n", code, *throw_jmp_handler);
+  longjmp(*throw_jmp_handler,code); /* !! or use siglongjmp ? */
 }
 
 static void 
 signal_throw(int sig)
 {
   int code;
+  debugp(stderr,"\ncaught signal %d\n", sig);
 
   switch (sig) {
   case SIGINT: code=-28; break;
@@ -131,6 +142,7 @@ signal_throw(int sig)
 static void
 sigaction_throw(int sig, siginfo_t *info, void *_)
 {
+  debugp(stderr,"\nsigaction_throw %d 0x%p 0x%p\n", sig, info, _);
   signal_throw(sig);
 }
 
@@ -139,6 +151,8 @@ static void fpe_handler(int sig, siginfo
 {
   int code;
 
+  debugp(stderr,"\nfpe_handler %d %x %x\n", sig, info, _);
+
   switch(info->si_code) {
 #ifdef FPE_INTDIV
   case FPE_INTDIV: code=BALL_DIVZERO; break;
@@ -185,6 +199,8 @@ static void segv_handler(int sig, siginf
   Address addr=info->si_addr;
   ImageHeader *h=gforth_header;
 
+  debugp(stderr,"\nsegv_handler %d 0x%p 0x%p\n", sig, info, _);
+
   if (JUSTUNDER(addr, h->data_stack_base))
     code=-3;
   else if (JUSTOVER(addr, NEXTPAGE(h->data_stack_base+h->data_stack_size)))
@@ -400,7 +416,7 @@ void install_signal_handlers(void)
   };
   int i;
   void (*throw_handler)() = die_on_signal ? graceful_exit : signal_throw;
-#ifdef SIGSTKSZ 
+#if defined(SIGSTKSZ) && defined(HAS_SIGALTSTACK)
   stack_t sigstack;
   int sas_retval=-1;
 
@@ -415,8 +431,7 @@ void install_signal_handlers(void)
     sas_retval=sigaltstack(&sigstack,(stack_t *)0);
   }
 #if defined(HAS_FILE) || !defined(STANDALONE)
-  if (debug)
-    fprintf(stderr,"sigaltstack: %s\n",strerror(sas_retval));
+  debugp(stderr,"sigaltstack: %s\n",strerror(sas_retval));
 #endif
 #endif