py-re2: failing to build for macOS 10.8, and broken since 2019 or earlier; mutex file not found

[mascguy (Christopher Nielsen)]

This port is failing to build for 10.8, across all Python 3.x releases. In every case, the issues appears to be the following:

building '_re2' extension
creating build/temp.macosx-10.8-x86_64-3.10
/opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_python_py-re2/py310-re2/work/compwrap/cc/usr/bin/clang++ -Wno-unused-result -Wsign-compare -Wunreachable-code -fno-common -dynamic -DNDEBUG -g -fwrapv -O3 -Wall -pipe -Os -arch x86_64 -isysroot/ -I/opt/local/Library/Frameworks/Python.framework/Versions/3.10/include/python3.10 -c _re2.cc -o build/temp.macosx-10.8-x86_64-3.10/_re2.o -std=c++11
In file included from _re2.cc:37:
/opt/local/include/re2/re2.h:209:10: fatal error: 'mutex' file not found
#include <mutex>
         ^
1 error generated.

CCing those that have committed changes to this port, from 2019 onward.

[reneeotten (Renee Otten)]

it builds everywhere else so its likely using C++11 stuff that isn't supported by the compiler that gets selected on 10.8. I have no way of troubleshooting this nor real interest to be honest.. do you need this for anything on 10.8 or you just noticed that it doesn't build?

[mascguy (Christopher Nielsen)]

Replying to reneeotten:

it builds everywhere else so its likely using C++11 stuff that isn't supported by the compiler that gets selected on 10.8. I have no way of troubleshooting this nor real interest to be honest.. do you need this for anything on 10.8 or you just noticed that it doesn't build?

It's blocking downstream builds of various dependents, so we really need to fix.

I quickly tried to fix, by blacklisting older Xcode clangs. But still fails, even when compiling with MacPorts Clang 13.

[kencu (Ken)]

a likely issue is that the wrong -stdlib is being used on 10.8.

clang on 10.8 defaults to -stdlib=libstdc++ if there is none specified on the build line.

If you can get -stdlib=libc++ onto the build line, then it will probably work. I say probably, because I altered the default behaviour for MacPorts' clangs to default to libc++ on appropriate MacPorts installs even on 10.8, so clang-13 should actually work.

But at any rate, best to get the stdlib onto the build line and then see what gives.

[reneeotten (Renee Otten)]

Replying to mascguy:

It's blocking downstream builds of various dependents, so we really need to fix.

its only dependent is mercurial so the fallout can't be that big...

But sure, @kencu his suggestion is certainly worth trying!

[jmroot (Joshua Root)]

Replying to reneeotten:

its only dependent is mercurial so the fallout can't be that big...

Not to mention nobody cared enough to file a ticket in 3+ years.

Anyway, Ryan pointed out the problem here: comment:9:ticket:64563

[mascguy (Christopher Nielsen)]

Replying to jmroot:

Anyway, Ryan pointed out the problem here: comment:9:ticket:64563

That works. Thanks Josh/Ryan!

[Christopher Nielsen <mascguy@…>]

In fd2aecb9040c8700f330dbbc8e65c5aef8d14766/macports-ports (master):

py-re2: fix builds for 10.8, via configure.cflags
Fixes: #64934

[mascguy (Christopher Nielsen)]

Forced 10.8 rebuilds of the two previously-blocked dependents, mercurial and git-remote-hg. And all is now well in 10.8 Land.

Thanks again folks!