gcc-devel: SDK version mismatch

[aivazis (Michael Aivazis)]

the gcc/g++ that come with gcc-devel are unable to find the system headers due to a mismatch in the name of the SDK:

~/tmp/c++>gcc -v -v -v str.c -o str
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/opt/local/libexec/gcc/arm64-apple-darwin20/11.0.0/lto-wrapper
Target: arm64-apple-darwin20
Configured with: /opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_lang_gcc-devel/gcc-devel/work/gcc-darwin-arm64-f335f738078a35dd48a0aaacbe58a0b7b11c86ce/configure --prefix=/opt/local --build=arm64-apple-darwin20 --enable-languages=c,c++,objc,obj-c++,lto,fortran,jit --libdir=/opt/local/lib/gcc-devel --includedir=/opt/local/include/gcc-devel --infodir=/opt/local/share/info --mandir=/opt/local/share/man --datarootdir=/opt/local/share/gcc-devel --with-local-prefix=/opt/local --with-system-zlib --disable-nls --program-suffix=-mp-devel --with-gxx-include-dir=/opt/local/include/gcc-devel/c++/ --with-gmp=/opt/local --with-mpfr=/opt/local --with-mpc=/opt/local --with-isl=/opt/local --enable-stage1-checking --disable-multilib --enable-lto --enable-libstdcxx-time --with-build-config=bootstrap-debug --with-as=/opt/local/bin/as --with-ld=/opt/local/bin/ld --with-ar=/opt/local/bin/ar --with-bugurl=https://trac.macports.org/newticket --enable-host-shared --disable-tls --with-pkgversion='MacPorts gcc-devel 11-20201205_0' --with-sysroot=/Library/Developer/CommandLineTools/SDKs/MacOSX11.0.sdk

but

~/tmp/c++>ls /Library/Developer/CommandLineTools/SDKs/MacOSX
MacOSX.sdk/      MacOSX10.15.sdk/ MacOSX11.1.sdk/

[kencu (Ken)]

We have no good plan for this just yet.

We have up until now tried to use an SDK that matches the system version we are building on, but that plan no longer seems viable.

While we debate the alternative, you will have to rebuild gcc (and many other ports) from source to pick up the name of your current SDK.

And whenever you upgrade your Xcode / CLTs, the same thing will happen.

We may decide to bake in MacOSX.sdk instead of a system-specific sdk, but this is still under debate.

[mascguy (Christopher Nielsen)]

Is this still an issue?

[aivazis (Michael Aivazis)]

I'm not sure. I have moved to gcc12, which works. Once in a while I get a linker warning about code that was built for a newer version than linked, but this seems to be more annoying than harmful. If there are no other volunteers, i'd be willing to try a recent gcc-devel install and test it.

[kencu (Ken)]

this was supposed to have been fixed by this commit:

​https://github.com/macports/macports-ports/commit/e8866c5019d60832527850b4e50fdc1de8878716

so I believe it is fixed.

[mascguy (Christopher Nielsen)]

Replying to kencu:

this was supposed to have been fixed by this commit:

​https://github.com/macports/macports-ports/commit/e8866c5019d60832527850b4e50fdc1de8878716

so I believe it is fixed.

Great, thanks Ken!