[Bug boehm-gc/66848] boehm-gc fails test suite on x86_64-apple-darwin15

[howarth.at.gcc at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66848

--- Comment #9 from Jack Howarth <howarth.at.gcc at gmail dot com> ---
Note that the earliest upstream boehm-gc release which builds and passes make
check on 10.11 is gc-7.2.tar.gz from http://www.hboehm.info/gc/gc_source/.
Diffing the current boehm-gc sources in gcc trunk suggests that the current FSF
boehm-gc is based on 7.1 (for at least mach_dep.c, etc).