[Bug lto/48180] New: '-fuse-linker-plugin' doesn't work.

[Bug lto/48180] New: '-fuse-linker-plugin' doesn't work.

[henry0312 at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48180

           Summary: '-fuse-linker-plugin' doesn't work.
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: lto
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: henry0312@gmail.com


I compiled gcc version 4.6.0 20110314 (prerelease) on Mac OS X 10.6.6.

configure options:
./configure\
    --build=x86_64-apple-darwin10\
    --disable-debug\
    --disable-multilib\
    --enable-threads=posix\
    --disable-bootstrap\
    --enable-version-specific-runtime-libs\
    --enable-languages=c,c++,objc,obj-c++\
    --enable-stage1-checking\
    --disable-nls\
    --enable-werror\
    --enable-lto\
    --enable-gold\
    --enable-ld\
    --with-system-zlib\
    --enable-fully-dynamic-string

And then,
following explanation of '-flto' (
http://gcc.gnu.org/onlinedocs/gcc-4.5.2/gcc/Optimize-Options.html#Optimize-Options
),
I tested my gcc.

$ gcc -flto -c a.c
$ gcc -flto -c b.c
$ gcc -o test -O2 -flto -fuse-linker-plugin a.o b.o
gcc: fatal error: -fuse-linker-plugin, but liblto_plugin.so not found
compilation terminated.

a.c and b.c --> http://www.privatepaste.com/34b31b77a5

My compiling environment:
gcc version 4.2.1 (Apple Inc. build 5666) (dot 3)
gmp-5.0.1
mpfr-3.0.0
mpc-0.9

[Bug target/48180] '-fuse-linker-plugin' doesn't work.

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48180

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Target|                            |x86_64-apple-darwin10
          Component|lto                         |target

--- Comment #1 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-03-18 14:15:45 UTC ---
LTO is not enabled by default on x86_64-apple-darwin10 and the apple linker
does not support a linker plugin compatible with LTO.

But yes, the error message could be improved to state this (no plugin
compatible linker available) instead of complaining the way it does.

[Bug lto/48180] '-fuse-linker-plugin' doesn't work.

[henry0312 at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48180

henry0312 at gmail dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
          Component|target                      |lto

--- Comment #2 from henry0312 at gmail dot com 2011-03-18 14:28:04 UTC ---
(In reply to comment #1)
> LTO is not enabled by default on x86_64-apple-darwin10 and the apple linker
> does not support a linker plugin compatible with LTO.
> 
> But yes, the error message could be improved to state this (no plugin
> compatible linker available) instead of complaining the way it does.


Should 'liblto_plugin.so' exist indeed?
Is this file created when compile gcc?

And If I compile binutils, will I be able to use '-fuse-linker-plugin'?

[Bug lto/48180] '-fuse-linker-plugin' doesn't work.

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48180

--- Comment #3 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-03-18 14:38:26 UTC ---
(In reply to comment #2)
> (In reply to comment #1)
> > LTO is not enabled by default on x86_64-apple-darwin10 and the apple linker
> > does not support a linker plugin compatible with LTO.
> > 
> > But yes, the error message could be improved to state this (no plugin
> > compatible linker available) instead of complaining the way it does.
> 
> 
> Should 'liblto_plugin.so' exist indeed?
> Is this file created when compile gcc?

I think it should exist, it is built and installed unconditionally.  See
the lto-plugin/ directory in your toplevel build directory.

> And If I compile binutils, will I be able to use '-fuse-linker-plugin'?

No, upstream GNU binutils do not have complete support for Mach-O.

[Bug lto/48180] '-fuse-linker-plugin' doesn't work.

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48180

--- Comment #4 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-03-18 14:40:23 UTC ---
(In reply to comment #3)
> (In reply to comment #2)
> > (In reply to comment #1)
> > > LTO is not enabled by default on x86_64-apple-darwin10 and the apple linker
> > > does not support a linker plugin compatible with LTO.
> > > 
> > > But yes, the error message could be improved to state this (no plugin
> > > compatible linker available) instead of complaining the way it does.
> > 
> > 
> > Should 'liblto_plugin.so' exist indeed?
> > Is this file created when compile gcc?
> 
> I think it should exist, it is built and installed unconditionally.  See
> the lto-plugin/ directory in your toplevel build directory.

I was wrong, lto-plugin only gets built for ELF targets and a small list
of extra targets that does not include x86_64-darwin10

[Bug lto/48180] '-fuse-linker-plugin' doesn't work.

[henry0312 at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48180

--- Comment #5 from henry0312 at gmail dot com 2011-03-18 14:50:59 UTC ---
(In reply to comment #4)
> (In reply to comment #3)
> > (In reply to comment #2)
> > > (In reply to comment #1)
> > > > LTO is not enabled by default on x86_64-apple-darwin10 and the apple linker
> > > > does not support a linker plugin compatible with LTO.
> > > > 
> > > > But yes, the error message could be improved to state this (no plugin
> > > > compatible linker available) instead of complaining the way it does.
> > > 
> > > 
> > > Should 'liblto_plugin.so' exist indeed?
> > > Is this file created when compile gcc?
> > 
> > I think it should exist, it is built and installed unconditionally.  See
> > the lto-plugin/ directory in your toplevel build directory.
> 
> I was wrong, lto-plugin only gets built for ELF targets and a small list
> of extra targets that does not include x86_64-darwin10

OK, I see.

Thank you very much.

[Bug lto/48180] '-fuse-linker-plugin' doesn't work.

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48180

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |WORKSFORME

--- Comment #6 from Richard Guenther <rguenth at gcc dot gnu.org> 2012-05-07 12:25:45 UTC ---
Works as expected.

[Bug lto/48180] '-fuse-linker-plugin' doesn't work.

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=48180

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |malcolm2190 at att dot net

--- Comment #7 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
*** Bug 81326 has been marked as a duplicate of this bug. ***