Re: Problem with parallel make with seq 2.2.4 on Linux

[Ben Franksen <benjamin.franksen@helmholtz-berlin.de>]

Am 14.01.2017 um 16:52 schrieb Ben Franksen:
> The problem is that snl.h is generated *and* that the dependency (.d)
> files generated by make use gcc for this.
>
> It seems that 'gcc -MM -MF' is not able to cope with not yet existing
> include files.

I have looked at the gcc docs and found this:

"""
-MG
    In conjunction with an option such as -M requesting dependency
generation, -MG assumes missing header files are generated files and
adds them to the dependency list without raising an error. The
dependency filename is taken directly from the #include directive
without prepending any path. -MG also suppresses preprocessed output, as
a missing header file renders this useless.

    This feature is used in automatic updating of makefiles.
"""

It seems to me that this is usually what one wants/expects. So perhaps
the EPICS build rules should use -MG when using gcc to generate .d files?

Cheers
Ben

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