Re: ld Linker extremely slow. Possible to optimze link time?

[Stephan Kuhagen]

Bernd Strieder wrote:

Hello

> What a coincidence

Yes, the same came to my mind, when I saw your post... ;-)

> When using templates a lot, a lot of functions are generated multiple
> times and the duplicates have to be removed by the linker. There are
> optimizations to improve that, some gcc make them possible, others not,
> this is what I found out.

Are there possibly some command line options to tweak some of these
optimizations? Using different compilers or self compiled versions of gcc
is not really an option for me, because I run a continuous build system
here which compiles several millions LOCs in a loop, using ccache and
distcc (which needs the same version of gcc on every compile host, and I'm
only responsible for half of them).

> I had some success with using self-compiled gcc, e.g. the latest 4.1
> prerelease 4.1.2-20070129, but I'm still trying to find out how to be
> sure to avoid the problem. We'll see, I hope.

Currently I use 4.1.1

> improvements, distro compilers used to be <=3.3 for a long time.
> Perhaps you had less problems with FC<6, do you remember?

I skipped FC5 and used FC4 before. As far as I remember, link times did not
change significantly between the versions. I think, the compiler version
was 3.4.x (x=4?).

Maybe some improvements can be done by some template usage tricks, so the
compiler/linker knows, which symbols/functions are needed? 

Regards
Stephan