From: Russ Cox <rsc@golang.org>
Date: Wed, 24 Jun 2015 21:31:57 +0000 (-0400)
Subject: cmd/compile: handle copy in escape analysis
X-Git-Tag: go1.5beta1~131
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=66130907d1483f851b514ab564c64fe1d1fceec6;p=gostls13.git

cmd/compile: handle copy in escape analysis

Somehow we missed this!
Fixes #11387.

Change-Id: Ida08fe52eff7da2ef7765b4cf35a39a301420c43
Reviewed-on: https://go-review.googlesource.com/11460
Reviewed-by: David Chase <drchase@google.com>
---

diff --git a/src/cmd/compile/internal/gc/esc.go b/src/cmd/compile/internal/gc/esc.go
index 020ca9b40c..85561cdb27 100644
--- a/src/cmd/compile/internal/gc/esc.go
+++ b/src/cmd/compile/internal/gc/esc.go
@@ -809,6 +809,9 @@ func esc(e *EscState, n *Node, up *Node) {
 		}
 		escassignDereference(e, &e.theSink, n.List.N) // The original elements are now leaked, too
 
+	case OCOPY:
+		escassignDereference(e, &e.theSink, n.Right) // lose track of assign of dereference
+
 	case OCONV, OCONVNOP:
 		escassign(e, n, n.Left)
 
diff --git a/test/escape2.go b/test/escape2.go
index c048f1b7aa..46cfde4a94 100644
--- a/test/escape2.go
+++ b/test/escape2.go
@@ -858,8 +858,8 @@ func foo103(m [1]*int, x *int) { // ERROR "foo103 m does not escape$" "foo103 x
 
 var y []*int
 
-// does not leak x
-func foo104(x []*int) { // ERROR "foo104 x does not escape$"
+// does not leak x but does leak content
+func foo104(x []*int) { // ERROR "leaking param content: x"
 	copy(y, x)
 }
 
@@ -1820,3 +1820,11 @@ func issue10353b() {
 	}
 	_ = f
 }
+
+func issue11387(x int) func() int {
+	f := func() int { return x }    // ERROR "func literal escapes to heap"
+	slice1 := []func() int{f}       // ERROR "\[\].* does not escape"
+	slice2 := make([]func() int, 1) // ERROR "make\(.*\) does not escape"
+	copy(slice2, slice1)
+	return slice2[0]
+}
diff --git a/test/escape2n.go b/test/escape2n.go
index f1481c1a36..c32877321f 100644
--- a/test/escape2n.go
+++ b/test/escape2n.go
@@ -858,8 +858,8 @@ func foo103(m [1]*int, x *int) { // ERROR "foo103 m does not escape$" "foo103 x
 
 var y []*int
 
-// does not leak x
-func foo104(x []*int) { // ERROR "foo104 x does not escape$"
+// does not leak x but does leak content
+func foo104(x []*int) { // ERROR "leaking param content: x"
 	copy(y, x)
 }
 
@@ -1820,3 +1820,11 @@ func issue10353b() {
 	}
 	_ = f
 }
+
+func issue11387(x int) func() int {
+	f := func() int { return x }    // ERROR "func literal escapes to heap"
+	slice1 := []func() int{f}       // ERROR "\[\].* does not escape"
+	slice2 := make([]func() int, 1) // ERROR "make\(.*\) does not escape"
+	copy(slice2, slice1)
+	return slice2[0]
+}