draco @1.5.6: error: no member named 'utimensat' in the global namespace

[nilason (Nicklas Larsson)]

The new port draco fail on build with following error:

[ 24%] Building CXX object CMakeFiles/draco_io.dir/src/draco/io/file_writer_utils.cc.o
/opt/local/bin/clang++-mp-16 -DDRACO_CMAKE=1 -DDRACO_FLAGS_SRCDIR=\"/opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_archivers_draco/draco/work/draco-1.5.6\" -DDRACO_FLAGS_TMPDIR=\"/tmp\" -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -I/opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_archivers_draco/draco/work/draco-1.5.6 -I/opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_archivers_draco/draco/work/draco-1.5.6/src -I/opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_archivers_draco/draco/work/build -I/opt/local/include/eigen3 -I/opt/local/include/ghc -I/opt/local/include -pipe -Os -DNDEBUG -I/opt/local/include -stdlib=libc++ -arch x86_64 -mmacosx-version-min=10.7 -fPIC -Wno-implicit-const-int-float-conversion -std=gnu++14 -MD -MT CMakeFiles/draco_io.dir/src/draco/io/file_writer_utils.cc.o -MF CMakeFiles/draco_io.dir/src/draco/io/file_writer_utils.cc.o.d -o CMakeFiles/draco_io.dir/src/draco/io/file_writer_utils.cc.o -c /opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_archivers_draco/draco/work/draco-1.5.6/src/draco/io/file_writer_utils.cc

...

In file included from /opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_archivers_draco/draco/work/draco-1.5.6/src/draco/io/file_writer_utils.cc:11:
/opt/local/include/ghc/filesystem.hpp:4681:11: error: no member named 'utimensat' in the global namespace
    if (::utimensat((int)AT_FDCWD, p.c_str(), times, AT_SYMLINK_NOFOLLOW) != 0) {
        ~~^
/opt/local/include/ghc/filesystem.hpp:4681:26: error: use of undeclared identifier 'AT_FDCWD'
    if (::utimensat((int)AT_FDCWD, p.c_str(), times, AT_SYMLINK_NOFOLLOW) != 0) {
                         ^
/opt/local/include/ghc/filesystem.hpp:4681:54: error: use of undeclared identifier 'AT_SYMLINK_NOFOLLOW'
    if (::utimensat((int)AT_FDCWD, p.c_str(), times, AT_SYMLINK_NOFOLLOW) != 0) {
                                                     ^
...

3 errors generated.
make[2]: *** [CMakeFiles/draco_io.dir/src/draco/io/file_writer_utils.cc.o] Error 1

Any pointers on how to deal with that would be greatly appreciated.

[jmroot (Joshua Root)]

It appears that ghc uses utimensat in its public headers, which means those headers can't be used without that function being available. As you've discovered, it's only available on macOS 10.13 and later. There is an implementation in legacysupport, but that means that all ghc dependents (or at least all those that include this particular header) are obliged to use legacysupport, which is unfortunate.

[ryandesign (Ryan Carsten Schmidt)]

Replying to jmroot:

It appears that ghc uses utimensat in its public headers, which means those headers can't be used without that function being available. As you've discovered, it's only available on macOS 10.13 and later. There is an implementation in legacysupport, but that means that all ghc dependents (or at least all those that include this particular header) are obliged to use legacysupport, which is unfortunate.

It's the ghc-filesystem port, not the ghc port, so that's a much smaller set of affected ports. I'll add legacysupport.

[ryandesign (Ryan Carsten Schmidt)]

In 844ca642120550004deee6f3b2fbbd76e7be4a6c/macports-ports (master):

draco: Add legacysupport for utimensat

Closes: #68438

[ryandesign (Ryan Carsten Schmidt)]

Replying to ryandesign:

It's the ghc-filesystem port, not the ghc port, so that's a much smaller set of affected ports.

And notably the "ghc" in ghc-filesystem stands for "​gulraks helper classes" and has nothing to do with the Glasgow Haskell Compiler.

[ryandesign (Ryan Carsten Schmidt)]

In 18890426714feb993b2d0f906277fa1d723a4cea/macports-ports (master):

input-leap: Add legacysupport for utimensat

See: #68438

[ryandesign (Ryan Carsten Schmidt)]

In 93fa1692c09831d6534376dad8deecc95b5ca4e6/macports-ports (master):

barrier: Add legacysupport for utimensat

See: #68438

[ryandesign (Ryan Carsten Schmidt)]

Replying to jmroot:

It appears that [ghc-filesystem] uses utimensat in its public headers

This was fixed in ghc-filesystem nine months ago and should be in the next release, at which time we can revert the legacysupport inclusion in all these ports. See #69740.