Using Link Time Optimization (LTO)

[Mike]

On Sunday, 23 March 2014 at 07:51:14 UTC, Johannes Pfau wrote:
>
> Some time ago LTO was only supported by the gold linker, so you 
> might
> need to configure binutils with --enable-gold --enable-plugins
> --enable-lto
>
> GCC should also be compiled with --enable-gold --enable-plugins
> --enable-lto
>
> http://gcc.gnu.org/onlinedocs/gcc-4.8.0/gcc/Optimize-Options.html
> also says if you link manually you must use gcc to link, not ld 
> and
> pass -flto when linking as well:
> gcc -o myprog -flto -O2 foo.o bar.o
>
> You can also try passing -fuse-linker-plugin to all gcc 
> commands.
>
> I never used LTO though, so I'm not sure if this will actually 
> help :-)

You were right, I have to link with gcc to get LTO to kick in.  
And sure enough Bug 88 symptoms appeared.  At least I now know 
why nothing was happening.  Thank you!