runtime: only permit SetCgoTraceback to be called once
Accept a duplicate call, but nothing else.
Change-Id: Iec24bf5ddc3b0f0c559ad2158339aca698601743
Reviewed-on: https://go-review.googlesource.com/23692
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
diff --git a/src/runtime/traceback.go b/src/runtime/traceback.go
index 96f154e2..80a5440 100644
--- a/src/runtime/traceback.go
+++ b/src/runtime/traceback.go
@@ -962,12 +962,21 @@
// traceback function will only be called with the context field set
// to zero. If the context function is nil, then calls from Go to C
// to Go will not show a traceback for the C portion of the call stack.
+//
+// SetCgoTraceback should be called only once, ideally from an init function.
func SetCgoTraceback(version int, traceback, context, symbolizer unsafe.Pointer) {
if version != 0 {
panic("unsupported version")
}
+ if cgoTraceback != nil && cgoTraceback != traceback ||
+ cgoContext != nil && cgoContext != context ||
+ cgoSymbolizer != nil && cgoSymbolizer != symbolizer {
+ panic("call SetCgoTraceback only once")
+ }
+
cgoTraceback = traceback
+ cgoContext = context
cgoSymbolizer = symbolizer
// The context function is called when a C function calls a Go
@@ -978,6 +987,7 @@
}
var cgoTraceback unsafe.Pointer
+var cgoContext unsafe.Pointer
var cgoSymbolizer unsafe.Pointer
// cgoTracebackArg is the type passed to cgoTraceback.
