[S] Change in coreboot[master]: util/crossgcc/buildgcc: Allow building CMake with multiple threads

[Felix Singer (Code Review)]

Attention is currently required from: Martin L Roth, Michael Niewöhner, Elyes Haouas.

Felix Singer has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/74156 )

Change subject: util/crossgcc/buildgcc: Allow building CMake with multiple threads
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Patch Set 1:

(1 comment)

Commit Message:

https://review.coreboot.org/c/coreboot/+/74156/comment/79ce7b14_88fa73f6 
PS1, Line 7: Allow building CMake with multiple threads
> not exactly - `--parallel` for `configure` only influences threads of builds done during configure. […]

I have tested this before uploading the patch. `--parallel` also seems to configure the threads which are used during the compilation. With `--parallel=1` only one thread was used, while `--parallel=32` made it using 32 threads.

If there is a configure flag for it, I rather want to use that instead of `make -j`. Though, I have to say I didn't check what the flag does :)