libgcc9 @9.5.0_2: compilation fails with error "gcc9 9.5.0 is not supported on Darwin 19 i386"

[jfgobin (Jean-François Gobin)]

Issue happened with "port upgrade outdated"

--->  Fetching distfiles for libgcc9
Error: gcc9 9.5.0 is not supported on Darwin 19 i386
Error: Failed to fetch libgcc9: incompatible macOS version

uname -a:
Darwin JeanFrancoisMBP 19.6.0 Darwin Kernel Version 19.6.0: Tue Jun 21 21:18:39 PDT 2022; root:xnu-6153.141.66~1/RELEASE_X86_64 x86_64

uname -p:
i386

uname -m:
x86_64

[mascguy (Christopher Nielsen)]

@cjones I'm also seeing this on my 10.15 installation.

[cjones051073 (Chris Jones)]

This is intentional.

With the rpath migration upstream has started with gcc 10, 11 and 12, older versions can no longer be supported, due to the way we share the libgcc runtime across all gcc versions. Upstream have indicated they may port support back to some older gcc releases, in due time, but until that happens we no longer can support gcc9 or older, on OSX 10.11 or newer, which are the OS version where gcc now relies on @rpath support.

You therefore need to migrate to a newer gcc version. If you have any ports using gcc9 variants, they will undoubtedly now have migrated to use a newer gcc variant by default, and you should uninstall any ports using gcc9 and reinstall with a newer variant.