1 files changed, 63 insertions, 0 deletions
diff --git a/src/runtime/traceback_windows.go b/src/runtime/traceback_windows.go
new file mode 100644
index 000000000..89dc1336e
--- /dev/null
+++ b/src/runtime/traceback_windows.go
@@ -0,0 +1,63 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import "unsafe"
+
+// sigtrampPC is the PC at the beginning of the jmpdefer assembly function.
+// The traceback needs to recognize it on link register architectures.
+var sigtrampPC uintptr
+
+func sigtramp()
+
+func init() {
+	sigtrampPC = funcPC(sigtramp)
+	systraceback = traceback_windows
+}
+
+func traceback_windows(f *_func, frame *stkframe, gp *g, printing bool, callback func(*stkframe, unsafe.Pointer) bool, v unsafe.Pointer) (changed, aborted bool) {
+	// The main traceback thinks it has found a function. Check this.
+
+	// Windows exception handlers run on the actual g stack (there is room
+	// dedicated to this below the usual "bottom of stack"), not on a separate
+	// stack. As a result, we have to be able to unwind past the exception
+	// handler when called to unwind during stack growth inside the handler.
+	// Recognize the frame at the call to sighandler in sigtramp and unwind
+	// using the context argument passed to the call. This is awful.
+	if f != nil && f.entry == sigtrampPC && frame.pc > f.entry {
+		var r *context
+		// Invoke callback so that stack copier sees an uncopyable frame.
+		if callback != nil {
+			frame.continpc = frame.pc
+			frame.argp = 0
+			frame.arglen = 0
+			if !callback(frame, v) {
+				aborted = true
+				return
+			}
+		}
+		r = (*context)(unsafe.Pointer(frame.sp + ptrSize))
+		frame.pc = contextPC(r)
+		frame.sp = contextSP(r)
+		frame.lr = 0
+		frame.fp = 0
+		frame.fn = nil
+		if printing && showframe(nil, gp) {
+			print("----- exception handler -----\n")
+		}
+		f = findfunc(frame.pc)
+		if f == nil {
+			print("runtime: unknown pc ", hex(frame.pc), " after exception handler\n")
+			if callback != nil {
+				gothrow("unknown pc")
+			}
+		}
+		frame.fn = f
+		changed = true
+		return
+	}
+
+	return
+}