Current `binaryen` fails to build against `gcc-12` as: https://hydra.nixos.org/build/245455591
[100%] Linking CXX executable ../../bin/binaryen-unittests
ld: /nix/store/...-gtest-1.12.1/lib/libgtest.so: undefined reference to `std::ios_base_library_init()@GLIBCXX_3.4.32'
collect2: error: ld returned 1 exit status
It is a typical mix of libraries built with `gcc-12` and bianries linked
with `gcc-12`'s `libstdc++`.
The change switches back to a default compiler and backports an upstream
`fmin` fix to amend the test.
c56c679c36