Re: [RFC PATCH] configure: remove all dependencies on a (re)configure

[Richard Henderson]

On 7/8/20 10:53 AM, Alex Bennée wrote:
> The previous code was brittle and missed cases such as the mipn32
> variants which for some reason has the 64 bit syscalls. This leads to
> a number of binary targets having deps lines like:
> 
>   all.clang-sanitizer/mipsn32el-linux-user/linux-user/signal.d
>   140:  /home/alex/lsrc/qemu.git/linux-user/mips64/syscall_nr.h \
>   455:/home/alex/lsrc/qemu.git/linux-user/mips64/syscall_nr.h:
> 
>   all.clang-sanitizer/mipsn32el-linux-user/linux-user/syscall.d
>   146:  /home/alex/lsrc/qemu.git/linux-user/mips64/syscall_nr.h \
>   485:/home/alex/lsrc/qemu.git/linux-user/mips64/syscall_nr.h:
> 
> which in turn would trigger the re-generation of syscall_nr.h in the
> source tree (thanks to generic %/syscall_nr.h rules). The previous
> code attempts to clean it out but misses edge cases but fails.
> 
> After spending a day trying to understand how this was happening I'm
> unconvinced that there are not other such breakages possible with this
> "caching". As we add more auto-generated code to the build it is likely
> to trip up again. Apply a hammer to the problem.
> 
> Fixes: 91e5998f18 (which fixes 5f29856b852d and 4d6a835dea47)
> Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
> ---
>  configure | 15 ++++++---------
>  1 file changed, 6 insertions(+), 9 deletions(-)

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

r~