Warn about unused results on release() for three scoped_ptr classes.

Depends on cleaning up existing uses of release().

BUG=42904
TEST=compile

Review URL: http://codereview.chromium.org/1783015

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@46649 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 6 insertions, 4 deletions

diff --git a/base/scoped_ptr.h b/base/scoped_ptr.h
index 34e4666a..c716e77 100644
--- a/base/scoped_ptr.h
+++ b/base/scoped_ptr.h
@@ -44,6 +44,8 @@
 #include <stdlib.h>
 #include <cstddef>
 
+#include "base/compiler_specific.h"
+
 // A scoped_ptr<T> is like a T*, except that the destructor of scoped_ptr<T>
 // automatically deletes the pointer it holds (if any).
 // That is, scoped_ptr<T> owns the T object that it points to.
@@ -113,7 +115,7 @@ class scoped_ptr {
   // If this object holds a NULL pointer, the return value is NULL.
   // After this operation, this object will hold a NULL pointer,
   // and will not own the object any more.
-  C* release() {
+  C* release() WARN_UNUSED_RESULT {
     C* retVal = ptr_;
     ptr_ = NULL;
     return retVal;
@@ -220,7 +222,7 @@ class scoped_array {
   // If this object holds a NULL pointer, the return value is NULL.
   // After this operation, this object will hold a NULL pointer,
   // and will not own the object any more.
-  C* release() {
+  C* release() WARN_UNUSED_RESULT {
     C* retVal = array_;
     array_ = NULL;
     return retVal;
@@ -337,7 +339,7 @@ class scoped_ptr_malloc {
   // If this object holds a NULL pointer, the return value is NULL.
   // After this operation, this object will hold a NULL pointer,
   // and will not own the object any more.
-  C* release() {
+  C* release() WARN_UNUSED_RESULT {
     C* tmp = ptr_;
     ptr_ = NULL;
     return tmp;
diff --git a/base/scoped_ptr_unittest.cc b/base/scoped_ptr_unittest.cc
index 9ea2289..99b1bc0 100644
--- a/base/scoped_ptr_unittest.cc
+++ b/base/scoped_ptr_unittest.cc
@@ -115,7 +115,7 @@ TEST(ScopedPtrTest, ScopedArray) {
   {
     scoped_array<ConDecLogger> scoper;
     EXPECT_FALSE(scoper.get());
-    scoper.release();
+    EXPECT_FALSE(scoper.release());
     EXPECT_FALSE(scoper.get());
     scoper.reset();
     EXPECT_FALSE(scoper.get());