1 files changed, 16 insertions, 14 deletions

diff --git a/src/pkg/runtime/sys_x86.c b/src/pkg/runtime/sys_x86.c
index 0df6dfbbd..a450b3e58 100644
--- a/src/pkg/runtime/sys_x86.c
+++ b/src/pkg/runtime/sys_x86.c
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build amd64 386
+// +build amd64 amd64p32 386
 
 #include "runtime.h"
 
@@ -14,6 +14,8 @@ runtime·gostartcall(Gobuf *gobuf, void (*fn)(void), void *ctxt)
 	uintptr *sp;
 	
 	sp = (uintptr*)gobuf->sp;
+	if(sizeof(uintreg) > sizeof(uintptr))
+		*--sp = 0;
 	*--sp = (uintptr)gobuf->pc;
 	gobuf->sp = (uintptr)sp;
 	gobuf->pc = (uintptr)fn;
@@ -27,7 +29,7 @@ void
 runtime·rewindmorestack(Gobuf *gobuf)
 {
 	byte *pc;
-	
+
 	pc = (byte*)gobuf->pc;
 	if(pc[0] == 0xe9) { // jmp 4-byte offset
 		gobuf->pc = gobuf->pc + 5 + *(int32*)(pc+1);
@@ -37,18 +39,18 @@ runtime·rewindmorestack(Gobuf *gobuf)
 		gobuf->pc = gobuf->pc + 2 + *(int8*)(pc+1);
 		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;
+	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");