[MacPorts] #63351: py-grpcio fails to build

[MacPorts]

#63351: py-grpcio fails to build
-------------------------+--------------------------
  Reporter:  mouse07410  |      Owner:  emcrisostomo
      Type:  defect      |     Status:  assigned
  Priority:  Normal      |  Milestone:
 Component:  ports       |    Version:
Resolution:              |   Keywords:
      Port:  py-grpcio   |
-------------------------+--------------------------

Comment (by mouse07410):

 > just lucky, I guess.

 So, when out of more than 1000 ports, about 990 build fine - you guess
 it's "just luck"?

 Note that {{{info:build Compiling with an SDK that doesn't seem to exist:
 /Library/Developer/CommandLineTools/SDKs/MacOSX11.sdk}}} is merely an
 **info** message - not an error. The actual compiler invocation proves
 that Macports does find the (mostly) correct SDK:
 {{{
 info:build
 /opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_devel_grpc/py39-grpcio/work/compwrap/cc/usr/bin/clang
 -Wno-unused-result <some stuff>
 -isysroot/Library/Developer/CommandLineTools/SDKs/MacOSX11.sdk -arch
 x86_64
 -isysroot/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX11.3.sdk
 -D_WIN32_WINNT=1536 -DGRPC_XDS_USER_AGENT_NAME_SUFFIX="Python" <some more
 stuff> -Isrc/python/grpcio -Iinclude -I. -Ithird_party/abseil-cpp
 -Ithird_party/address_sorting/include -I/opt/local/include
 -I/opt/local/include/re2 -I/opt/local/include/openssl -Ithird_party/upb
 -Isrc/core/ext/upb-generated -Isrc/core/ext/upbdefs-generated
 -Ithird_party/xxhash -I/opt/local/include
 -I/opt/local/Library/Frameworks/Python.framework/Versions/3.9/include/python3.9
 -c third_party/upb/upb/table.c -o
 python_build/temp.macosx-11.0-x86_64-3.9/third_party/upb/upb/table.o
 -stdlib=libc++ -fvisibility=hidden -fno-wrapv -fno-exceptions
 -DHAVE_UNISTD_H -pthread
 }}}

 Observe **two** {{{-isysroot}}} flags, one with wrong/nonexistent path,
 the other one pointing to a symlink to the right SDK.

 > And we still don't know if putting the sdk back will fix you.

 I'm 99.999% sure it won't/can't.

 Considering that {{{/Library/Developer/CommandLineTools}}} contains plenty
 of stuff, not just the SDK itself - I'm very much leery of (no offense
 meant!) "vivisecting" the SDK, as the likelihood of breaking other stuff
 in a more serious way because the rest of the CLT is not there is pretty
 high.

 > It's just "step 1".

 Let's just proceed to "step 2". ;-)

-- 
Ticket URL: <https://trac.macports.org/ticket/63351#comment:14>
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