Dump stack trace on segfault in the VM.

runtime/bin/platform_macos.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "platform/globals.h"
 #if defined(TARGET_OS_MACOS)
 
 #include "bin/platform.h"
 
 #if !TARGET_OS_IOS
@@ skipping 10 matching lines @@
 #include "bin/file.h"
 
 namespace dart {
 namespace bin {
 
 const char* Platform::executable_name_ = NULL;
 char* Platform::resolved_executable_name_ = NULL;
 int Platform::script_index_ = 1;
 char** Platform::argv_ = NULL;
 
+
+static void segv_handler(int signal, siginfo_t* siginfo, void* context) {
+  Dart_DumpNativeStackTrace(context);
+  abort();
+}
+
 bool Platform::Initialize() {
   // Turn off the signal handler for SIGPIPE as it causes the process
   // to terminate on writing to a closed pipe. Without the signal
   // handler error EPIPE is set instead.
   struct sigaction act;
   bzero(&act, sizeof(act));
   act.sa_handler = SIG_IGN;
   if (sigaction(SIGPIPE, &act, 0) != 0) {
     perror("Setting signal handler failed");
     return false;
   }
+  act.sa_flags = SA_SIGINFO;
+  act.sa_sigaction = &segv_handler;
+  if (sigemptyset(&act.sa_mask) != 0) {
+    perror("sigemptyset() failed.");
+    return false;
+  }
+  if (sigaddset(&act.sa_mask, SIGPROF) != 0) {
+    perror("sigaddset() failed");
+    return false;
+  }
+  if (sigaction(SIGSEGV, &act, NULL) != 0) {
+    perror("sigaction() failed.");
+    return false;
+  }
   return true;
 }
 
 
 int Platform::NumberOfProcessors() {
   int32_t cpus = -1;
   size_t cpus_length = sizeof(cpus);
   if (sysctlbyname("hw.logicalcpu", &cpus, &cpus_length, NULL, 0) == 0) {
     return cpus;
   } else {
@@ skipping 79 matching lines @@
 
 
 void Platform::Exit(int exit_code) {
   exit(exit_code);
 }
 
 }  // namespace bin
 }  // namespace dart
 
 #endif  // defined(TARGET_OS_MACOS)