diff --git a/src/runtime/stack1.go b/src/runtime/stack1.go
index 6a1f6aee926..3f89bb17390 100644
--- a/src/runtime/stack1.go
+++ b/src/runtime/stack1.go
@@ -466,9 +466,10 @@ func adjustframe(frame *stkframe, arg unsafe.Pointer) bool {
 	}
 
 	// Adjust saved base pointer if there is one.
-	if thechar == '6' && frame.argp-frame.varp == 2*ptrSize {
+	if thechar == '6' && frame.argp-frame.varp == 2*regSize {
 		if !framepointer_enabled {
 			print("runtime: found space for saved base pointer, but no framepointer experiment\n")
+			print("argp=", hex(frame.argp), " varp=", hex(frame.varp), "\n")
 			throw("bad frame layout")
 		}
 		if stackDebug >= 3 {
diff --git a/src/runtime/traceback.go b/src/runtime/traceback.go
index c8134533991..4f63502e85c 100644
--- a/src/runtime/traceback.go
+++ b/src/runtime/traceback.go
@@ -235,7 +235,7 @@ func gentraceback(pc0 uintptr, sp0 uintptr, lr0 uintptr, gp *g, skip int, pcbuf
 		// If framepointer_enabled and there's a frame, then
 		// there's a saved bp here.
 		if GOARCH == "amd64" && frame.varp > frame.sp && framepointer_enabled {
-			frame.varp -= ptrSize
+			frame.varp -= regSize
 		}
 
 		// Derive size of arguments.