Re: Question about ld tests requiring plugins support

["Bin.Cheng" <amker dot cheng at gmail dot com>]

On Tue, Aug 26, 2014 at 5:32 PM, Nicholas Clifton <nickc@redhat.com> wrote:
> Hi Bin,
>
>
>> I ran into ld/lto testing failures of my arm/aarch64 toolchain.  The
>
>
>> BFD: tmpdir/lto-12c.o: plugin needed to handle lto object
>
>
> Try recreating your toolchain.  This time add "--enable-plugins" to the
> configure command line.

Hi Nick, thanks for helping.  I tried with that both for gcc and
binutils, but no luck.

After looking into lto.exp, I found below code snippet.

set plugin_names {
    liblto_plugin.so
    liblto_plugin-0.dll
    cyglto_plugin-0.dll
}
set plug_opt ""
foreach plug $plugin_names {
    set plug_so [run_host_cmd $CC "--print-file-name $plug"]
    if { $plug_so ne $plug } then {
    set plug_opt "--plugin $plug_so"
    break
    }
}

For my toolchain, the check always output the file name, rather than
the full path of the plugins.
/home/binche01/work/target-aarch64-none-elf/bin/aarch64-none-elf-gcc
-B/home/binche01/work/build-aarch64-none-elf/obj/binutils/ld/tmpdir/ld/
  -L/home/binche01/work/target-aarch64-none-elf/aarch64-none-elf/lib
--print-file-name liblto_plugin.so
liblto_plugin.so

Even file "liblto_plugin.so" does exist in the installation place:
.../target-aarch64-none-elf/libexec/gcc/aarch64-none-elf/5.0.0/liblto_plugin.so

That's why "--plugin ...." is set to empty string.

Interesting thing is gcc manually says that:

-print-file-name=libraryPrint the full absolute name of the library
file library that would be used when linking--and don't do anything
else. With this option, GCC does not compile or link anything; it just
prints the file name.
Thanks,
bin

>
> Cheers
>   Nick
>
>