Unfortunately, adding a DEBUG_ASSERT_MSG_FMT isn't actually possible
right now because of compiler bugs:
https://github.com/dolphin-emu/dolphin/pull/9284
We could require a newer version of GCC (10) but that would require
updating GCC on the build machines.
For what it's worth, older versions of GCC (8, 9) are broken in
many ways: adding constexpr to some Matrix functions causes GCC 8
to generate bugged code that causes the Wii IR pointer to disappear,
which means that the generated builds are already unusable
(see https://dolp.in/i12324).
Additionally, we've already had to add workarounds for those versions
in the format macros to fix compilation bugs. This time, it looks like
workarounds won't cut it; even applying the workaround
described in https://github.com/fmtlib/fmt/pull/1580 does not help.
Léo Lam
c0f7f91507