Index: src/pkg/runtime/sys_x86.c |
=================================================================== |
--- a/src/pkg/runtime/sys_x86.c |
+++ b/src/pkg/runtime/sys_x86.c |
@@ -27,7 +27,6 @@ |
runtime·rewindmorestack(Gobuf *gobuf) |
{ |
byte *pc; |
- Func *f; |
pc = (byte*)gobuf->pc; |
if(pc[0] == 0xe9) { // jmp 4-byte offset |
@@ -38,12 +37,18 @@ |
gobuf->pc = gobuf->pc + 2 + *(int8*)(pc+1); |
return; |
} |
- if(pc[0] == 0xcc) { // breakpoint inserted by gdb |
- f = runtime·findfunc(gobuf->pc); |
- if(f != nil) { |
- gobuf->pc = f->entry; |
- return; |
- } |
+ if(pc[0] == 0xcc) { |
+ // This is a breakpoint inserted by gdb. We could use |
+ // runtime·findfunc to find the function. But if we |
+ // do that, then we will continue execution at the |
+ // function entry point, and we will not hit the gdb |
+ // breakpoint. So for this case we don't change |
+ // gobuf->pc, so that when we return we will execute |
+ // the jump instruction and carry on. This means that |
+ // stack unwinding may not work entirely correctly |
+ // (http://golang.org/issue/5723) but the user is |
+ // running under gdb anyhow. |
+ return; |
} |
runtime·printf("runtime: pc=%p %x %x %x %x %x\n", pc, pc[0], pc[1], pc[2], pc[3], pc[4]); |
runtime·throw("runtime: misuse of rewindmorestack"); |