Use gcc-nm instead of nm. Same applies for ar and ranlib, btw.
On 08.01.2016 08:41, Prathamesh Kulkarni wrote:
Hi,
I am having issues building GNU toolchain with LTO support.
When I compile a "hello world" file with gcc,
gcc -O2 -c hello.c -flto
nm hello.o gives the following warning:
plugin needed to handle lto object
How do I work around this problem ?
using -fuse-linker-plugin didn't help either.
gcc -dumpspecs has following entries:
%(linker) %{!fno-use-linker-plugin:%{!fno-lto: -plugin
%(linker_plugin_file) -plugin-opt=%(lto_wrapper)
-plugin-opt=-fresolution=%u.res
%{!nostdlib:%{!nodefaultlibs:%:pass-through-libs(%(link_gcc_c_sequence))}}
}}%{flto|flto=*:%<fcompare-debug*} %{flto} %{fno-lto}
%{flto=*} %l %{no-pie:}
I did the following to build toolchain:
a) configured binutils-2.25 with --enable-gold --enable-lto
--enable-plugins --prefix=$INSTALL
b) configured gcc trunk with --with-plugin-ld=$INSTALL/bin/ld.bfd
--prefix=$INSTALL --enable-languages=c,c++,lto
I currently use the wrappers for nm/ar/ranlib mentioned in following
link in Prerequisites section:
http://hubicka.blogspot.in/2014/04/linktime-optimization-in-gcc-2-firefox.html
Thanks,
Prathamesh
