https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68771
--- Comment #20 from Daniel Vollmer <zerolo at gmail dot com> --- Interesting. The gcc-7.4.0 was the bottled (precompiled) version from homebrew, generated on Dec 7th 2018, so I assume it must've been built on 10.14.1 or 10.14.2. I rebuilt 7.4.0 locally just now (so in 10.14.4), and now I can no longer reproduce the problem. I'm not sure what could cause the difference, though... (Also, I had to patch a system header for compiling g++-7.4.0 in /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/sys/ucred.h in 10.14.4 to not use _Atomic in C++ mode, as seemingly only clang understands that).
