Can gcc use multiple cores when linking?

Question

So when compiling tons of source files with GCC one can use -j to use all available cores. But what about the linker? Is there a similar option to speed up linking or does GCC not support multi-threading? In some larger projects it can really take a while ... (... and I hate to wait!)

Edit: Thanks for pointing out that -j is a option for make and not gcc/g++. But this does not answer my question! I would like to know if gcc can use multi threading while linking a program!

Answer 1

Try gold, which was developed by Ian Lance Taylor et al. from Google and released as part of GNU binutils package.

From Wikipedia:

The motivation for writing gold was to make a linker that is faster than the GNU linker, especially for large applications coded in C++

I must admit I haven't tried it myself yet but it's mentioned on WebKitGTK project webpage.

For more information see an article written by the author of gold: A New ELF Linker.

More importantly, see the work on incremental / parallel / concurrent linking by Sander Mathijs van Veen titled Concurrent Linking with the GNU Gold Linker and the bibliography therein.

Answer 2

lld, the linker developed by the LLVM project, will use multiple cores by default. I have also found it to be about 2x faster than gold running with multiple threads (-Wl,--threads -Wl,--thread-count,xxx)