---
 include/ruby/win32.h |    3 +
 vm_dump.c            |    2 +
 win32/win32.c        |  108 ++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 113 insertions(+), 0 deletions(-)

diff --git a/include/ruby/win32.h b/include/ruby/win32.h
index 7b6bded..db646b2 100644
--- a/include/ruby/win32.h
+++ b/include/ruby/win32.h
@@ -672,6 +672,9 @@ in asynchronous_func_t.
 typedef uintptr_t (*asynchronous_func_t)(uintptr_t self, int argc, uintptr_t* argv);
 uintptr_t rb_w32_asynchronize(asynchronous_func_t func, uintptr_t self, int argc, uintptr_t* argv, uintptr_t intrval);
 
+/* backtrace */
+void rb_w32_backtrace();
+
 #if defined __GNUC__ && __GNUC__ >= 4
 #pragma GCC visibility pop
 #endif
diff --git a/vm_dump.c b/vm_dump.c
index f245ccc..c0199b1 100644
--- a/vm_dump.c
+++ b/vm_dump.c
@@ -616,5 +616,7 @@ rb_vm_bugreport(void)
 	}
 	fprintf(stderr, "\n");
     }
+#elif _WIN32
+    rb_w32_backtrace();
 #endif
 }
diff --git a/win32/win32.c b/win32/win32.c
index 46cdafa..b9d9713 100644
--- a/win32/win32.c
+++ b/win32/win32.c
@@ -36,6 +36,9 @@
 #ifdef __MINGW32__
 #include <mswsock.h>
 #endif
+#if _MSC_VER && _M_IX86
+#include <DbgHelp.h>
+#endif
 #include "ruby/win32.h"
 #include "win32/dir.h"
 #define isdirsep(x) ((x) == '/' || (x) == '\\')
@@ -5694,3 +5697,108 @@ signbit(double x)
     return *ip < 0;
 }
 #endif
+
+#if _MSC_VER && _M_IX86
+static struct DumpArgs {
+    DWORD thread_id;
+    HANDLE event;
+};
+
+static void
+dump_thread(void *arg)
+{
+    struct DumpArgs* dump_args = (struct DumpArgs*)arg;
+    HANDLE process = GetCurrentProcess();
+    HANDLE thread = OpenThread(THREAD_ALL_ACCESS, 0, dump_args->thread_id);
+    STACKFRAME64 stackFrame;
+    CONTEXT context;
+    BOOL bool_rc;
+    DWORD64 dwDisplacement;
+    DWORD64 dwAddress;
+    char buffer[sizeof(SYMBOL_INFO) + MAX_SYM_NAME * sizeof(TCHAR)];
+    PSYMBOL_INFO pSymbol = (PSYMBOL_INFO)buffer;
+    IMAGEHLP_LINE64 line;
+    DWORD dwLineDisplacement;
+
+    SymSetOptions(SYMOPT_UNDNAME | SYMOPT_DEFERRED_LOADS | SYMOPT_DEBUG | SYMOPT_LOAD_LINES);
+
+    if (!SymInitialize(process, NULL, TRUE)) abort();
+
+    memset(&context, 0, sizeof(CONTEXT));
+    context.ContextFlags = CONTEXT_FULL;
+    bool_rc = GetThreadContext(thread, &context);
+    if(!bool_rc) abort();
+
+    memset(&stackFrame,0,sizeof(STACKFRAME64));
+    stackFrame.AddrPC.Mode = AddrModeFlat;
+    stackFrame.AddrPC.Offset = context.Eip;
+
+    stackFrame.AddrFrame.Mode = AddrModeFlat;
+    stackFrame.AddrFrame.Offset = context.Ebp;
+
+    stackFrame.AddrStack.Mode = AddrModeFlat;
+    stackFrame.AddrStack.Offset = context.Esp;
+
+    fprintf(stderr, "-- C level backtrace information "
+            "-------------------------------------------\n");
+
+    while(1)
+    {
+	bool_rc = StackWalk64(
+	    IMAGE_FILE_MACHINE_I386,
+	    process,
+	    thread,
+	    &stackFrame,
+	    (PVOID)&context,
+	    NULL,
+	    SymFunctionTableAccess64,
+	    SymGetModuleBase64,
+	    NULL);
+	if(!bool_rc) break;
+
+        dwDisplacement = 0;
+        dwAddress = stackFrame.AddrPC.Offset;
+
+	memset(buffer, 0, sizeof(buffer));
+	pSymbol->SizeOfStruct = sizeof(SYMBOL_INFO);
+	pSymbol->MaxNameLen = MAX_SYM_NAME;
+
+	if (SymFromAddr(process, dwAddress, &dwDisplacement, pSymbol))
+	{
+            fprintf(stderr, "(%s)", pSymbol->Name);
+	}
+
+	memset(&line, 0, sizeof(IMAGEHLP_LINE64));
+	line.SizeOfStruct = sizeof(IMAGEHLP_LINE64);
+
+	if (SymGetLineFromAddr64(process, dwAddress, &dwLineDisplacement, &line))
+	{
+            fprintf(stderr, "(%s:%lu)", line.FileName, line.LineNumber);
+	}
+
+        fprintf(stderr, " [0x%08I64x]\n", dwAddress);
+    }
+    fprintf(stderr, "\n");
+
+    if (!CloseHandle(thread)) abort();
+    if (!SymCleanup(process)) abort();
+    if (!SetEvent(dump_args->event)) abort();
+}
+
+void 
+rb_w32_backtrace() {
+    struct DumpArgs dump_args;
+    dump_args.thread_id = GetCurrentThreadId();
+    dump_args.event = CreateEvent(NULL, TRUE, FALSE, NULL);
+    if(!dump_args.event) abort();
+    _beginthread(dump_thread,0,&dump_args);
+
+    if (WaitForSingleObject(dump_args.event, INFINITE) != WAIT_OBJECT_0) abort();
+}
+#elif
+void 
+rb_w32_backtrace() {
+}
+#endif
+
+
--