RE: [PATCH] race in parallel out-of-tree build

[Johansson Erik-E. <eri...@mo...>]

> -----Original Message-----
> From: Paul Mundt [mailto:le...@li...]
> Hmm.. Have you actually seen this as a problem? An easy way to
reproduce,
> or at least a log of the error would be nice. I don't seem to have any
> luck reproducing this. maketools depends on version.h, which is
generated
> by prepare1 in the top-level, which comes after archprepare in the
.PHONY
> list. The dependency ordering is explicit, in that each stage depends
on
> the previous one, so I still don't see anything wrong here. On the
other
> hand, if this is a valid bug, ARM also has this problem.

Output from building with -j 16 without my patch:
  GEN     <long_path>/kernel-debug/Makefile
  SYMLINK include/asm -> include/asm-sh
  CHK     include/linux/version.h
  Using <long_path>/linux-2.6.17 as source for kernel
  SPLIT   include/linux/autoconf.h -> include/config/*
  UPD     include/linux/version.h
  SYMLINK include/asm-sh/cpu -> include/asm-sh/cpu-sh4
  Generating include/asm-sh/machtypes.h
/bin/sh: include/asm-sh/machtypes.h: No such file or directory
  SYMLINK include/asm-sh/mach -> include/asm-sh/stb7100ref
make[3]: *** [include/asm-sh/machtypes.h] Error 1
make[2]: *** [maketools] Error 2
make[2]: *** Waiting for unfinished jobs....

The error above is what you get if you run (without an include/asm-sh
dir):
/bin/sh -c 'awk -f gen-mach-types mach-types >
include/asm-sh/machtypes.h'

The same, but with my patch:
  GEN     <long_path>/kernel-debug/Makefile
  SYMLINK include/asm -> include/asm-sh
  SPLIT   include/linux/autoconf.h -> include/config/*
  CHK     include/linux/version.h
  Using <long_path>/linux-2.6.17 as source for kernel
  UPD     include/linux/version.h
  Generating include/asm-sh/machtypes.h
  SYMLINK include/asm-sh/cpu -> include/asm-sh/cpu-sh4
  SYMLINK include/asm-sh/mach -> include/asm-sh/stb7100ref

In both cases you see that Generating include/asm-sh/machtypes.h comes
before creating the two symlinks (cpu and mach).

/Erik