[Bug binutils/20343] Document how to use LTO

[markus at trippelsdorf dot de]

https://sourceware.org/bugzilla/show_bug.cgi?id=20343

Markus Trippelsdorf <markus at trippelsdorf dot de> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |markus at trippelsdorf dot de

--- Comment #1 from Markus Trippelsdorf <markus at trippelsdorf dot de> ---
(In reply to address@hidden from comment #0)
> Please document what the user has to do, in order to use LTO with ld, gold,
> nm, ar, ranlib in regards to the -?-plugin option.  In particular, 
> 
> * when is 'compiler -print-prog-name=...' called to find the plugin,
> * if it is not called by nm, ar, ranlib, how to the latter find the linker
> plugin
> * how can different plugins coexist (for gcc and clang, and for different
> versions of gcc)

Yes. At least it works for gcc and clang. Different versions of gcc are
compatible right now,
so you can just use the latest plugin and it should work with older gcc
versions, too. (This could change in the future.)

> * how is the directory bfd-plugins supposed to be used

Just add symlinks to the plugins, e.g.:

address@hidden ~ % ls -al /usr/x86_64-pc-linux-gnu/binutils-bin/lib/bfd-plugins/
total 8
drwxr-xr-x 1 root root 66 Jun  3 13:17 .
drwxr-xr-x 1 root root 22 Jun 27  2015 ..
lrwxrwxrwx 1 root root 65 Apr 27 13:32 liblto_plugin.so.0.0.0 ->
/usr/libexec/gcc/x86_64-pc-linux-gnu/6.1.1/liblto_plugin.so.0.0.0
lrwxrwxrwx 1 root root 28 Jun  3 13:17 LLVMgold.so ->
/usr/local/lib64/LLVMgold.so

> * in which binutils versions have the aforementioned behaviours changed

plugins coexistence was added in 2014.

-- 
You are receiving this mail because:
You are on the CC list for the bug.