Re: [PATCH mingw/gold] Fix mingw gold build with plugins enabled for non-dlfcn case

[Ian Lance Taylor <iant at google dot com>]

On Wed, Jan 9, 2013 at 6:35 AM, Pavel Chupin <pavel.v.chupin@gmail.com> wrote:
> On Sat, Jan 5, 2013 at 11:18 PM, Ian Lance Taylor <iant@google.com> wrote:
>> On Fri, Dec 28, 2012 at 10:41 AM, Pavel Chupin <pavel.v.chupin@gmail.com> wrote:
>>
>>> Attached patch fixes mingw build configured (for example) as:
>>>
>>> ../configure --prefix=`pwd`/../INSTALL --target=i686-linux-android
>>> --host=i586-pc-mingw32msvc --build=i386-linux-gnu --enable-plugins
>>> --enable-gold
>>> make
>>>
>>> Error message:
>>>
>>> ../../gold/plugin.cc:32:19: fatal error: dlfcn.h: No such file or directory
>>>
>>> I'm fixing it like it's done in bfd configure: check for headers and
>>> library, add/not-add -ldl on link.
>>> Also adding windows.h case into plugin.cc to handle case when
>>> mingw-dlfcn is not installed on the system.
>>>
>>> ChangeLog:
>>>
>>> 2012-12-25  Pavel Chupin  <pavel.v.chupin@intel.com>
>>>
>>>        Fix mingw gold build with plugins enabled
>>>        * gold/Makefile.am: Replace -ldl with @lt_cv_dlopen_libs@.
>>>        * gold/aclocal.m4: Include libtool modules.
>>>        * gold/configure.ac: Export lt_cv_dlopen_libs and add headers check.
>>>        * gold/plugin.cc: Handle non-dlfcn case.
>>>        * gold/Makefile.in: Regenerate.
>>>        * gold/config.in: Regenerate.
>>>        * gold/configure: Regenerate.
>>>        * gold/testsuite/Makefile.in: Regenerate.
>>
>> Sorry for the slow review.  The general idea is fine but the
>> formatting is wrong.  This is C++ code, not C: no space between
>> function name and left parenthesis.  Keep line lengths less than 80
>> columns--the body of dlsym needs a line break.  Don't define
>> dlclose--it's not called.  dlerror should return an ordinary error
>> string--no capitalization, no punctuation.
>>
>> In configure.ac, the comment should be a complete sentence with proper
>> capitalization and punctuation.  It should explain why you are using
>> libtool.
>>
>> Thanks.
>>
>> Ian
>
> Hi Ian,
> Thanks for review. Please see modified patch attached.

Hmmmm, there is a problem here.  You have introduced the use of
libtool into configure.ac when it was not there before.  When I run
autoreconf, this causes automake to rebuild the linker Makefile to use
libtool rather than the simple commands that it used before.  I'm not
at all sure that that is a good idea.

Can we get this information without using libtool?

Ian