Re: gmake and ccache conspiring together in creating gremlins

Hi Sam,=0A=
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Thanks for a delightfully illuminating analysis.=0A=
I hope you enjoyed the sleuthing, even if it did cost you a month !=0A=
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> The TLDR of the above: make reads the job server's file descriptors=0A=
> from the MAKEFLAGS environment variable, then checks here if they=0A=
> actually exist. If they don't exist, make will create the job server=0A=
> pipe. Important: by default they will be file descriptors 3 and 4.=0A=
> This becomes a key player in this mystery, a little bit later.=0A=
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> When make spawns a child job (other than a recursive make) the job=0A=
> server file descriptors get closed (marked O_CLOEXEC before the actual=0A=
> execve), but MAKEFLAGS remains in the environment.=0A=
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Sounds to me like that's a bug: when the descriptors are closed, the=0A=
part of MAKEFLAGS that claims they're make's jobserver file descriptors=0A=
should be removed, since that's when the claim stops being true.=0A=
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	Eddy.=0A=