svn commit: r518679 - in head/devel/dmlc-core: . files

[Jan Beich]

Piotr Kubaj <pkubaj at FreeBSD.org> writes:

> Author: pkubaj
> Date: Fri Nov 29 22:24:45 2019
> New Revision: 518679
> URL: https://svnweb.freebsd.org/changeset/ports/518679
>
> Log:
>   devel/dmlc-core: fix build on GCC architectures
>   
>   Use USES=compiler:openmp instead of hard dependency on ports LLVM. Use new GCC when using base GCC.

- USES=compiler:openmp currently forces GCC. See also bug 210337.
- GCC uses libstdc++ which cannot be used together with libc++
  due to a conflict between libsupc++ and libcxxrt [1]

$ echo 'int main() {}' >a.c
$ cc a.c -L/usr/local/lib -ldmlc -ltvm
$ ./a.out
Segmentation fault
$ ldd a.out | fgrep c++
        libstdc++.so.6 => /usr/local/lib/gcc9/libstdc++.so.6 (0x801b97000)
        libc++.so.1 => /usr/lib/libc++.so.1 (0x8023f5000)

[1] https://wiki.freebsd.org/NewC++Stack#Mixing_Libraries_using_Libc.2B-.2B-_and_Libstdc.2B-.2B-
    https://svnweb.freebsd.org/changeset/base/233749