From 5cf4e442a5dc1f4a1d6f3fd04b1083bc192e648e Mon Sep 17 00:00:00 2001 From: Alex Brainman Date: Fri, 25 Jan 2019 18:56:22 +1100 Subject: [PATCH] runtime: fix syscall.NewCallback to return all bits for uintptr values syscall.NewCallback mistakenly used MOVL even for windows/amd64, which only returned the lower 32 bits regardless of the architecture. This was due to a copy and paste after porting from windows/386. The code now uses MOVQ, which will return all the available bits. Also adjust TestReturnAfterStackGrowInCallback to ensure we never regress. Fixes #29331 Change-Id: I4f5c8021c33f234c2bb7baa9ef7a6b4870172509 Reviewed-on: https://go-review.googlesource.com/c/159579 Run-TryBot: Emmanuel Odeke TryBot-Result: Gobot Gobot Reviewed-by: Emmanuel Odeke Reviewed-by: Keith Randall --- src/runtime/sys_windows_amd64.s | 2 +- src/runtime/syscall_windows_test.go | 8 ++++++-- 2 files changed, 7 insertions(+), 3 deletions(-) diff --git a/src/runtime/sys_windows_amd64.s b/src/runtime/sys_windows_amd64.s index 612f0a474d..43a26497ad 100644 --- a/src/runtime/sys_windows_amd64.s +++ b/src/runtime/sys_windows_amd64.s @@ -351,7 +351,7 @@ TEXT runtime·callbackasm1(SB),NOSPLIT,$0 ADDQ $64, SP POPFQ - MOVL -8(CX)(DX*1), AX // return value + MOVQ -8(CX)(DX*1), AX // return value POPQ -8(CX)(DX*1) // restore bytes just after the args RET diff --git a/src/runtime/syscall_windows_test.go b/src/runtime/syscall_windows_test.go index 3ad6512976..5335c12f0f 100644 --- a/src/runtime/syscall_windows_test.go +++ b/src/runtime/syscall_windows_test.go @@ -655,12 +655,16 @@ uintptr_t cfunc(callback f, uintptr_t n) { r uintptr err syscall.Errno } + want := result{ + // Make it large enough to test issue #29331. + r: (^uintptr(0)) >> 24, + err: 333, + } c := make(chan result) go func() { - r, _, err := proc.Call(cb, 100) + r, _, err := proc.Call(cb, want.r) c <- result{r, err.(syscall.Errno)} }() - want := result{r: 100, err: 333} if got := <-c; got != want { t.Errorf("got %d want %d", got, want) } -- 2.50.0