runtime: traceback running goroutines
Introduce freezetheworld function that is a best-effort attempt to stop any concurrently running goroutines. Call it during crash.
Fixes #5873.
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/12054044
diff --git a/src/pkg/runtime/runtime.h b/src/pkg/runtime/runtime.h
index 2529a0f..7d04a75 100644
--- a/src/pkg/runtime/runtime.h
+++ b/src/pkg/runtime/runtime.h
@@ -837,6 +837,7 @@
int64 runtime·nanotime(void);
void runtime·dopanic(int32);
void runtime·startpanic(void);
+void runtime·freezetheworld(void);
void runtime·unwindstack(G*, byte*);
void runtime·sigprof(uint8 *pc, uint8 *sp, uint8 *lr, G *gp);
void runtime·resetcpuprofiler(int32);
