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-rw-r--r--test/fixedbugs/issue16095.go104
1 files changed, 104 insertions, 0 deletions
diff --git a/test/fixedbugs/issue16095.go b/test/fixedbugs/issue16095.go
new file mode 100644
index 0000000..864b4b7
--- /dev/null
+++ b/test/fixedbugs/issue16095.go
@@ -0,0 +1,104 @@
+// run
+
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "fmt"
+ "runtime"
+)
+
+var sink *[20]byte
+
+func f() (x [20]byte) {
+ // Initialize x.
+ for i := range x {
+ x[i] = byte(i)
+ }
+
+ // Force x to be allocated on the heap.
+ sink = &x
+ sink = nil
+
+ // Go to deferreturn after the panic below.
+ defer func() {
+ recover()
+ }()
+
+ // This call collects the heap-allocated version of x (oops!)
+ runtime.GC()
+
+ // Allocate that same object again and clobber it.
+ y := new([20]byte)
+ for i := 0; i < 20; i++ {
+ y[i] = 99
+ }
+ // Make sure y is heap allocated.
+ sink = y
+
+ panic(nil)
+
+ // After the recover we reach the deferreturn, which
+ // copies the heap version of x back to the stack.
+ // It gets the pointer to x from a stack slot that was
+ // not marked as live during the call to runtime.GC().
+}
+
+var sinkint int
+
+func g(p *int) (x [20]byte) {
+ // Initialize x.
+ for i := range x {
+ x[i] = byte(i)
+ }
+
+ // Force x to be allocated on the heap.
+ sink = &x
+ sink = nil
+
+ // Go to deferreturn after the panic below.
+ defer func() {
+ recover()
+ }()
+
+ // This call collects the heap-allocated version of x (oops!)
+ runtime.GC()
+
+ // Allocate that same object again and clobber it.
+ y := new([20]byte)
+ for i := 0; i < 20; i++ {
+ y[i] = 99
+ }
+ // Make sure y is heap allocated.
+ sink = y
+
+ // panic with a non-call (with no fallthrough)
+ for {
+ sinkint = *p
+ }
+
+ // After the recover we reach the deferreturn, which
+ // copies the heap version of x back to the stack.
+ // It gets the pointer to x from a stack slot that was
+ // not marked as live during the call to runtime.GC().
+}
+
+func main() {
+ x := f()
+ for i, v := range x {
+ if v != byte(i) {
+ fmt.Printf("%v\n", x)
+ panic("bad f")
+ }
+ }
+ x = g(nil)
+ for i, v := range x {
+ if v != byte(i) {
+ fmt.Printf("%v\n", x)
+ panic("bad g")
+ }
+ }
+}