For what it's worth, we didn't handle it as well as we could have, but Gentoo tooling did throw up a red flag "something is wrong": https://bugs.gentoo.org/951124 libtool: link: x86_64-pc-linux-gnu-gcc -m32 -mfpmath=sse -march=native -O3 -pipe -flto=auto -Werror=odr -Werror=lto-type-mismatch -Werror=strict-aliasing -D_GNU_SOURCE -Wl,-O1 -Wl,-z -Wl,pack-relative-relocs -fuse-ld=mold -o src/.libs/mpg123 src/audio.o src/common.o src/sysutil.o src/control_generic.o src/equalizer.o src/getlopt.o src/httpget.o...
Typo in option check for -Wl,--export-dynamic
5.2 build log
Buil fails with strict-aliasing violations
tests: migrate from external mock package to stdlib unittest.mock
Compilation fails when autotools is not installed.
Building flightgear with LTO fails due to ODR violation
I can't try current trunk as it doesn't build since [r14858]. Regenerating the autotools now breaks once it hits that directory. No time to investigate tonight.