Fix the build with gcc 4.7.0

• Component: Tools / Tests
• Status: RESOLVED FIXED

[Andras Becsi]

Building WebKit with the recently released gcc 4.7.0 is not possible because the compiler has a few new warning messages which make the build fail because of Werror.

[Andras Becsi]

Created attachment 136470 [details]
proposed fix

[Build Bot]

Comment on attachment 136470 [details]
proposed fix

Attachment 136470 [details] did not pass mac-ews (mac):
Output: http://queues.webkit.org/results/12379515

[Andras Becsi]

Created attachment 136473 [details]
updated patch

[Andras Becsi]

Created attachment 136474 [details]
updated patch with updated changelog

*sigh*

[Alexey Proskuryakov]

Comment on attachment 136474 [details]
updated patch with updated changelog

View in context: https://bugs.webkit.org/attachment.cgi?id=136474&action=review

> Source/WebCore/html/HTMLImageElement.cpp:76
> -    if (optionalHeight > 0)
> +    if (optionalHeight)

Heh.

[Andras Becsi]

Comment on attachment 136474 [details]
updated patch with updated changelog

Clearing flags on attachment: 136474

Committed r113848: <http://trac.webkit.org/changeset/113848>

[Andras Becsi]

All reviewed patches have been landed.  Closing bug.

Still fails with error:

g++: error: unrecognized command line option ‘-fuse-ld=gold’

on x86_64 architecture. It works if I manually edit 'Tools/qmake/mkspecs/features/unix/default_post.prf' removing lines 41-46.

[Balazs Kelemen]

(In reply to comment #8)
> Still fails with error:
> 
> g++: error: unrecognized command line option ‘-fuse-ld=gold’
> 
> on x86_64 architecture. It works if I manually edit 'Tools/qmake/mkspecs/features/unix/default_post.prf' removing lines 41-46.

Strange. Do you use the same gcc for building qt and webkit?

[Andras Becsi]

(In reply to comment #8)
> Still fails with error:
> 
> g++: error: unrecognized command line option ‘-fuse-ld=gold’
> 
> on x86_64 architecture. It works if I manually edit 'Tools/qmake/mkspecs/features/unix/default_post.prf' removing lines 41-46.

You have to build Qt with the same compiler you try to build WebKit, since the QT_GCC_FOO_VERSION variables are set on compile time of Qt.

So if your Qt was built with gcc 4.6 (or older), then the check does not work, and the -fuse-ld=gold is appended.

There should probably be a version check for the actual compiler in the WebKit codebase, but this is not trivial since we support a myriad of compilers. 
And additionally, this is a transition problem which should be fixed by the Qt packagers of the distribution / the provider of your Qt.

[Andras Becsi]

(In reply to comment #10)
> (In reply to comment #8)
> > Still fails with error:
> > 
> > g++: error: unrecognized command line option ‘-fuse-ld=gold’
> > 
> > on x86_64 architecture. It works if I manually edit 'Tools/qmake/mkspecs/features/unix/default_post.prf' removing lines 41-46.
> 
> You have to build Qt with the same compiler you try to build WebKit, since the QT_GCC_FOO_VERSION variables are set on compile time of Qt.
> 
> So if your Qt was built with gcc 4.6 (or older), then the check does not work, and the -fuse-ld=gold is appended.
> 
> There should probably be a version check for the actual compiler in the WebKit codebase, but this is not trivial since we support a myriad of compilers. 
> And additionally, this is a transition problem which should be fixed by the Qt packagers of the distribution / the provider of your Qt.

This made me wonder if we should consider removing the QMAKE_LFLAGS += -fuse-ld=gold line altogether and require developers to set ld.gold as the default linker if they want to use it.

Tor Arne, what do you think?

To reply Balazs and Andras: I use Qt binary package provided by my OS (Arch Linux), which is (most probably) compiled with gcc 4.6. Thanks for clarification.