diff options
-rw-r--r-- | src/internal/abi/abi.go | 18 | ||||
-rw-r--r-- | src/reflect/all_test.go | 23 | ||||
-rw-r--r-- | src/reflect/value.go | 19 |
3 files changed, 57 insertions, 3 deletions
diff --git a/src/internal/abi/abi.go b/src/internal/abi/abi.go index aaff9cece3..aa5083a666 100644 --- a/src/internal/abi/abi.go +++ b/src/internal/abi/abi.go @@ -33,6 +33,24 @@ type RegArgs struct { ReturnIsPtr IntArgRegBitmap } +func (r *RegArgs) Dump() { + print("Ints:") + for _, x := range r.Ints { + print(" ", x) + } + println() + print("Floats:") + for _, x := range r.Floats { + print(" ", x) + } + println() + print("Ptrs:") + for _, x := range r.Ptrs { + print(" ", x) + } + println() +} + // IntArgRegBitmap is a bitmap large enough to hold one bit per // integer argument/return register. type IntArgRegBitmap [(IntArgRegs + 7) / 8]uint8 diff --git a/src/reflect/all_test.go b/src/reflect/all_test.go index eac27e886f..6f350affd6 100644 --- a/src/reflect/all_test.go +++ b/src/reflect/all_test.go @@ -6270,6 +6270,29 @@ func TestCallMethodJump(t *testing.T) { *CallGC = false } +func TestCallArgLive(t *testing.T) { + type T struct{ X, Y *string } // pointerful aggregate + + F := func(t T) { *t.X = "ok" } + + // In reflect.Value.Call, trigger a garbage collection in reflect.call + // between marshaling argument and the actual call. + *CallGC = true + + x := new(string) + runtime.SetFinalizer(x, func(p *string) { + if *p != "ok" { + t.Errorf("x dead prematurely") + } + }) + v := T{x, nil} + + ValueOf(F).Call([]Value{ValueOf(v)}) + + // Stop garbage collecting during reflect.call. + *CallGC = false +} + func TestMakeFuncStackCopy(t *testing.T) { target := func(in []Value) []Value { runtime.GC() diff --git a/src/reflect/value.go b/src/reflect/value.go index 6f878eba5b..520dc69137 100644 --- a/src/reflect/value.go +++ b/src/reflect/value.go @@ -352,7 +352,7 @@ func (v Value) CallSlice(in []Value) []Value { return v.call("CallSlice", in) } -var callGC bool // for testing; see TestCallMethodJump +var callGC bool // for testing; see TestCallMethodJump and TestCallArgLive const debugReflectCall = false @@ -509,12 +509,16 @@ func (v Value) call(op string, in []Value) []Value { // Copy values to "integer registers." if v.flag&flagIndir != 0 { offset := add(v.ptr, st.offset, "precomputed value offset") - memmove(unsafe.Pointer(®Args.Ints[st.ireg]), offset, st.size) - } else { if st.kind == abiStepPointer { // Duplicate this pointer in the pointer area of the // register space. Otherwise, there's the potential for // this to be the last reference to v.ptr. + regArgs.Ptrs[st.ireg] = *(*unsafe.Pointer)(offset) + } + memmove(unsafe.Pointer(®Args.Ints[st.ireg]), offset, st.size) + } else { + if st.kind == abiStepPointer { + // See the comment in abiStepPointer case above. regArgs.Ptrs[st.ireg] = v.ptr } regArgs.Ints[st.ireg] = uintptr(v.ptr) @@ -539,6 +543,15 @@ func (v Value) call(op string, in []Value) []Value { // Mark pointers in registers for the return path. regArgs.ReturnIsPtr = abi.outRegPtrs + if debugReflectCall { + regArgs.Dump() + } + + // For testing; see TestCallArgLive. + if callGC { + runtime.GC() + } + // Call. call(frametype, fn, stackArgs, uint32(frametype.size), uint32(abi.retOffset), uint32(frameSize), ®Args) |