991227 - clang 3.5 build warning: gfx/layers/LayerScope.cpp:460:35: warning: 'auto_ptr' is deprecated [-Wdeprecated-declarations]

Status: RESOLVED FIXED

(Core :: Graphics: Layers, defect)

Description

[Daniel Holbert [:dholbert]]

Build warning, with clang 3.5:

gfx/layers/LayerScope.cpp:460:35: warning: 'auto_ptr' is deprecated [-Wdeprecated-declarations]

Some googling for "auto_ptr" and "deprecated" confirms that it indeed is deprecated in favor of C++11 unique_ptr. e.g.:
 http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2005/n1856.html#20.4.5%20-%20Class%20template%20auto_ptr


Anyway -- auto_ptr is deprecated, and unique_ptr probably isn't avaiable everywhere yet, so I suspect we should be using nsAutoPtr here (?)

Comment 1

[Boris Chiou [:boris]]

Attachment: [WIP] Replace std::auto_ptr with nsAutoPtr in LayerScope (v1)

std::auto_ptr causes clang 3.5 build warnings because we shouldn't use
std::auto_ptr in C++ 11 anymore. auto_ptr is deprecated in clang 3.5.
Therefore I replaced all the std::auto_ptrs in LayerScope.cpp.

Comment 2

[Boris Chiou [:boris]]

(In reply to Boris Chiou [:boris] from comment #1)
> Created attachment 8445711 [details] [diff] [review]
> [WIP] Replace std::auto_ptr with nsAutoPtr in LayerScope (v1)
> 
> std::auto_ptr causes clang 3.5 build warnings because we shouldn't use
> std::auto_ptr in C++ 11 anymore. auto_ptr is deprecated in clang 3.5.
> Therefore I replaced all the std::auto_ptrs in LayerScope.cpp.

I found a problem. We shouldn't use auto_ptr<> or nsAutoPtr<> with moz_malloc() because the destructor of nsAutoPtr/auto_ptr calls "delete", not "free()", so I will upload a patch to use nsAutoArrayPtr<> and "new char[]".

Comment 3

[Boris Chiou [:boris]]

Attachment: Replace std::auto_ptr with nsAuto(Array)Ptr in LayerScope

std::auto_ptr causes clang 3.5 build warnings because we shouldn't use
std::auto_ptr in C++ 11 anymore. auto_ptr is deprecated in clang 3.5.
Therefore I replaced all the std::auto_ptrs in LayerScope.cpp.
Note: nsAuto(Array)Ptr should use "new" operator in C++, instead of
moz_malloc() because the destructor of nsAuto(Array)Ptr will call
delete(delete []).

try result:
https://tbpl.mozilla.org/?tree=Try&rev=157562bf8384

Comment 4

[Boris Chiou [:boris]]

Attachment: Replace std::auto_ptr with nsAuto(Array)Ptr in LayerScope (v2)

std::auto_ptr causes clang 3.5 build warnings because we shouldn't use
std::auto_ptr in C++ 11 anymore. auto_ptr is deprecated in clang 3.5.
Therefore I replaced all the std::auto_ptrs in LayerScope.cpp.
Note: nsAuto(Array)Ptr should use "new" operator in C++, instead of
moz_malloc() because the destructor of nsAuto(Array)Ptr will call
delete(delete []).

try result:
https://tbpl.mozilla.org/?tree=Try&rev=9aad4d949d9e

Comment 5

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/84f3f9b84bbb

Comment 6

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

https://hg.mozilla.org/mozilla-central/rev/84f3f9b84bbb

Comment 7

[Jeff Muizelaar [:jrmuizel]]

nsAutoPtr can now be replaced by mozilla::UniquePtr

Comment 8

[Boris Chiou [:boris]]

(In reply to Jeff Muizelaar [:jrmuizel] from comment #7)
> nsAutoPtr can now be replaced by mozilla::UniquePtr

Great! Thanks for your comment, Jeff. I will replace them in other bug. :)

Comment 9

[Boris Chiou [:boris]]

(In reply to Boris Chiou [:boris] from comment #8)
> (In reply to Jeff Muizelaar [:jrmuizel] from comment #7)
> > nsAutoPtr can now be replaced by mozilla::UniquePtr
> 
> Great! Thanks for your comment, Jeff. I will replace them in other bug. :)

By the way, Do you have any reference link? I cannot find mozilla::UniquePtr or mozilla:unique_ptr in dxr right now. Thanks.

Comment 10

[Jeff Muizelaar [:jrmuizel]]

It looks like dxr hasn't been updated yet.

Take a look at http://hg.mozilla.org/mozilla-central/file/75f66f8cb99f/mfbt/UniquePtr.h

The semantics should be basically the same as std::unique_ptr

Comment 11

[Boris Chiou [:boris]]

(In reply to Jeff Muizelaar [:jrmuizel] from comment #10)
> It looks like dxr hasn't been updated yet.
> 
> Take a look at
> http://hg.mozilla.org/mozilla-central/file/75f66f8cb99f/mfbt/UniquePtr.h
> 
> The semantics should be basically the same as std::unique_ptr

So cool. Thank you very much. It's really a good news.