parsing multithreading make's output (-j N)

I have a lot of source directories in common directory. When I start make by issuing command:

make -j 4

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I receive a lot of strings from make's threads along with invoked gcc compiler instances. For parsing errors I have to run make twice, second time with one thread:

make -j 1

so I can correctly parse make's output.

Is there a way for running multithreaded make one time and correctly decide which error related to which project (source directory)?

Thank you!

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If you are using recursive make (naughty boy) together with -j, then you can wrap Make with a shell script which prefixes each line of output with a unique per-make-invocation string.

$ cat M
#!/bin/bash
PREFIX=$$:
exec -a $0 make "$@" 2>&1 | sed "s/^/$PREFIX/"

Now, assuming your makefiles correctly use ${MAKE} to indicate recursion, we can use ./M instead of make.

$ ./M -j --no-print-directory target
28720:/home/user/M -fa.mak
28720:/home/user/M -fb.mak
28720:/home/user/M -fc.mak
28720:/home/user/M -fd.mak
28720:/home/user/M -fe.mak
28720:32484:gcc blah...
28720:31936:/home/user/M -fanother.mak
28720:32484:gcc blah...
28720:31936:gcc blah...
28720:31936:gcc blah...
28720:31936:56781:echo blah...
∶

In this case, each line is prefixed with a list of process IDs (good for debugging recursive make). For your use case, you may prefer M to mangle source file names so that they become absolute pathnames in error messages.

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May be it is possible to switch to pmake?

PMake is set up to handle the output from multiple jobs in a graceful fashion (source)

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If you're using some kind of meta-build system (eg CMake) try using Ninja to actually run the build.

It solves this problem as well as being quite a lot faster.