From c85fd1fe35669ec6b653451ca1c966899ffca394 Mon Sep 17 00:00:00 2001
From: Gavin Whelan <gavwhela@gmail.com>
Date: Tue, 4 Mar 2014 14:48:59 -0800
Subject: [PATCH] Fixed Linux specific bug causing lack of stack overflow
 traces.

---
 v/loop.c | 12 ++++++++++--
 v/main.c | 12 ++++++++++--
 2 files changed, 20 insertions(+), 4 deletions(-)

diff --git a/v/loop.c b/v/loop.c
index b1e76dd5e..c6a588d80 100644
--- a/v/loop.c
+++ b/v/loop.c
@@ -42,6 +42,14 @@ typedef enum {
 
 volatile u2_kill Sigcause;            //  reasons for exception
 
+static void _lo_cont(void *arg1, void *arg2, void *arg3)
+{
+  (void)(arg1);
+  (void)(arg2);
+  (void)(arg3);
+  siglongjmp(Signal_buf, 1);
+}
+
 static void
 _lo_signal_handle_over(int emergency, stackoverflow_context_t scp)
 {
@@ -60,7 +68,7 @@ _lo_signal_handle_over(int emergency, stackoverflow_context_t scp)
 #endif
   {
     Sigcause = sig_overflow;
-    longjmp(Signal_buf, 1);
+    sigsegv_leave_handler(_lo_cont, NULL, NULL, NULL);
   }
 }
 
@@ -329,7 +337,7 @@ u2_lo_soft(u2_reck* rec_u, c3_w sec_w, u2_funk fun_f, u2_noun arg)
   u2_unix_ef_hold();
   _lo_signal_deep(sec_w);
 
-  if ( 0 != setjmp(Signal_buf) ) {
+  if ( 0 != sigsetjmp(Signal_buf, 1) ) {
     u2_noun tax, pre, mok;
 
     //  return to blank state
diff --git a/v/main.c b/v/main.c
index 64fb278dd..ec50a5ed5 100644
--- a/v/main.c
+++ b/v/main.c
@@ -246,6 +246,14 @@ static uint8_t Sigstk[SIGSTKSZ];
 
 volatile enum { sig_none, sig_overflow, sig_interrupt } Sigcause;
 
+static void _main_cont(void *arg1, void *arg2, void *arg3)
+{
+  (void)(arg1);
+  (void)(arg2);
+  (void)(arg3);
+  siglongjmp(Signal_buf, 1);
+}
+
 static void
 overflow_handler(int emergency, stackoverflow_context_t scp)
 {
@@ -254,7 +262,7 @@ overflow_handler(int emergency, stackoverflow_context_t scp)
     exit(1);
   } else {
     Sigcause = sig_overflow;
-    longjmp(Signal_buf, 1);
+    sigsegv_leave_handler(_main_cont, NULL, NULL, NULL);
   }
 }
 
@@ -367,7 +375,7 @@ main(c3_i   argc,
   //  we get a signal, we force the system back into the just-booted state.
   //  If anything goes wrong during boot (above), it's curtains.
   {
-    if ( 0 != setjmp(Signal_buf) ) {
+    if ( 0 != sigsetjmp(Signal_buf, 1) ) {
       switch ( Sigcause ) {
         case sig_overflow: printf("[stack overflow]\r\n"); break;
         case sig_interrupt: printf("[interrupt]\r\n"); break;