possible miscompilation on macOS Catalina 10.15.6

[Trevor Spiteri]

On 28/10/2020 12:14, Torbjörn Granlund wrote:
> Trevor Spiteri <tspiteri at ieee.org> writes:
>
>   I maintain Rust language bindings to GMP and got a bug report from a
>   user on macOS Catalina 10.15.6.  I do not know if this issue is caused
>   by the particular system setup of the user or if it is more general, so
>   I'm listing what information I have in case it is actually reproducible
>   in a more general setting.
>
>   The bindings compilation process compiles GMP using:
>
>   ln -s path/to/extracted/gmp-6.2.0 gmp-src
>   mkdir gmp-build
>   cd gmp-build
>   ../gmp-src/configure --enable-fat --disable-shared --with-pic
>   make -j 8
>   make -j 8 check
>
>   The make check is failing and outputting this on standard error:
>
>   ../../../gmp-src/test-driver: line 107: 4825 Segmentation fault: 11 "$@"
>   > $log_file 2>&1
>   make[5]: *** [test-suite.log] Error 1
>   make[4]: *** [check-TESTS] Error 2
>   make[3]: *** [check-am] Error 2
>   make[2]: *** [check-recursive] Error 1
>   make[1]: *** [check-recursive] Error 1
>   make: *** [check] Error 2
>
>   I don't have standard output, so I don't know which test actually failed.
>
>   This is all the information I got; sorry if it is incomplete. (The
>   user's issue was solved by using their already installed homebrew?
>   libraries instead of compiling GMP anew.)
>
> OK, so *some* compiler compiled GMP with and *some* GMP test program
> reported a segfault.  I will right away start the natural deduction over
> all possible instances of compilers and GMP test cases. Oh wait, I need
> to consider all possible CPUs and relevant environment variables as
> well.

Sorry for not being clearer: I was only concerned that there was a
chance the combination

    configure --enable-fat --disable-shared --with-pic

might cause issues with Catalina's default compiler, if there even is
such a thing, and since I don't have such a system I couldn't test it
myself. If that's not the case, then the rest is of course useless
information.