macports-libcxx does not support +universal on Intel?

[barracuda156]

Trying to install tiledb on 10.8 got me this:

10:~ svacchanda$ sudo port -v install tiledb
Error: Cannot install tiledb for the archs 'i386 x86_64' because
Error: its dependency macports-libcxx is only installed for the arch 'x86_64'
Error: and does not have a universal variant.
Error: Unable to execute port: architecture mismatch

[ryandesign (Ryan Carsten Schmidt)]

The macports-libcxx port is weird. It doesn't build anything; it just copies and installs files that were installed by the clang-11 port. So macports-libcxx's architectures and universality depend on the archs and universality for which the clang-11 port was installed. This does not seem great.

[kencu (Ken)]

It was expedient to just copy the already-built lib++ out of clang-11 rather than rebuild it, but as the Portfile says

“ # for now, we will leverage the already-built libc++ in the appropriate clang port # later, we can build this independently if we choose to do so, much like libtapi “

It’s easy enough to rebuilt all of the desired clang and then copy the libc++ out of it.

Slightly more complicated would be to set up a new build that only installs libc++… for the universal build of that, Apple uses a shell script. One of the Apple engineers showed me where it was one time… let me see if I can find it for you…

[kencu (Ken)]

here it is:

​https://github.com/llvm/llvm-project/blob/main/libcxx/utils/ci/apple-install-libcxx.sh

And here’s the thread I started about it a few years ago:

​https://lists.llvm.org/pipermail/libcxx-dev/2021-April/001116.html

[barracuda156]

Replying to kencu:

here it is:

​https://github.com/llvm/llvm-project/blob/main/libcxx/utils/ci/apple-install-libcxx.sh

And here’s the thread I started about it a few years ago:> ​https://lists.llvm.org/pipermail/libcxx-dev/2021-April/001116.html

Thank you!

Maybe Kirill @catap will be interested in the topic too, could we tag him?

[kencu (Ken)]

now, about there being no universal macports-libcxx… it may have just never come up before….

as clang-11 seems to exist universal on all the needed systems, it might be as simple as adding a blank universal variant to macports-libcxx!

why don’t you give that a try?

variant universal {}

[barracuda156]

Replying to ryandesign:

The macports-libcxx port is weird. It doesn't build anything; it just copies and installs files that were installed by the clang-11 port. So macports-libcxx's architectures and universality depend on the archs and universality for which the clang-11 port was installed. This does not seem great.

I actually have clang-11 as universal though. (Besides, wouldn't it be better to use clang-11-bootstrap?)

[kencu (Ken)]

Replying to barracuda156:

Maybe Kirill @catap will be interested in the topic too, could we tag him?

Sure! Go ahead!

[kencu (Ken)]

Replying to barracuda156:

(Besides, wouldn't it be better to use clang-11-bootstrap?)

Right up until someone wants macports-libcxx to be based on a newer clang, like, clang-15…

then, you’re DOA :)

[catap (Kirill A. Korinsky)]

Replying to barracuda156:

I actually have clang-11 as universal though. (Besides, wouldn't it be better to use clang-11-bootstrap?)

It builds only clang and compiler-rt :)

Thus, it might be linked with gcc10-bootstrap libgcc_s ;)

[catap (Kirill A. Korinsky)]

to be honest all llvm ports can be done as universal but it will lead to 2x building time and need to revdump all of them. Seems like a week of overload build bots.

[kencu (Ken)]

In 759116ba564f7b9d6673c35933d653d8de89d2f9/macports-ports (master):

macports-libcxx: add a default universal variant

closes: #67922

[kencu (Ken)]

$ port contents | grep dylib | xargs file
/opt/local/lib/libcxx/libc++.1.0.dylib:    Mach-O universal binary with 2 architectures: [x86_64:Mach-O 64-bit dynamically linked shared library x86_64] [i386:Mach-O dynamically linked shared library i386]
/opt/local/lib/libcxx/libc++.1.0.dylib (for architecture x86_64):	Mach-O 64-bit dynamically linked shared library x86_64
/opt/local/lib/libcxx/libc++.1.0.dylib (for architecture i386):	Mach-O dynamically linked shared library i386
/opt/local/lib/libcxx/libc++.1.dylib:      Mach-O universal binary with 2 architectures: [x86_64:Mach-O 64-bit dynamically linked shared library x86_64] [i386:Mach-O dynamically linked shared library i386]
/opt/local/lib/libcxx/libc++.1.dylib (for architecture x86_64):	Mach-O 64-bit dynamically linked shared library x86_64
/opt/local/lib/libcxx/libc++.1.dylib (for architecture i386):	Mach-O dynamically linked shared library i386
/opt/local/lib/libcxx/libc++.dylib:        Mach-O universal binary with 2 architectures: [x86_64:Mach-O 64-bit dynamically linked shared library x86_64] [i386:Mach-O dynamically linked shared library i386]
/opt/local/lib/libcxx/libc++.dylib (for architecture x86_64):	Mach-O 64-bit dynamically linked shared library x86_64
/opt/local/lib/libcxx/libc++.dylib (for architecture i386):	Mach-O dynamically linked shared library i386
/opt/local/lib/libcxx/libc++abi.1.0.dylib: Mach-O universal binary with 2 architectures: [x86_64:Mach-O 64-bit dynamically linked shared library x86_64] [i386:Mach-O dynamically linked shared library i386]
/opt/local/lib/libcxx/libc++abi.1.0.dylib (for architecture x86_64):	Mach-O 64-bit dynamically linked shared library x86_64
/opt/local/lib/libcxx/libc++abi.1.0.dylib (for architecture i386):	Mach-O dynamically linked shared library i386
/opt/local/lib/libcxx/libc++abi.1.dylib:   Mach-O universal binary with 2 architectures: [x86_64:Mach-O 64-bit dynamically linked shared library x86_64] [i386:Mach-O dynamically linked shared library i386]
/opt/local/lib/libcxx/libc++abi.1.dylib (for architecture x86_64):	Mach-O 64-bit dynamically linked shared library x86_64
/opt/local/lib/libcxx/libc++abi.1.dylib (for architecture i386):	Mach-O dynamically linked shared library i386
/opt/local/lib/libcxx/libc++abi.dylib:     Mach-O universal binary with 2 architectures: [x86_64:Mach-O 64-bit dynamically linked shared library x86_64] [i386:Mach-O dynamically linked shared library i386]
/opt/local/lib/libcxx/libc++abi.dylib (for architecture x86_64):	Mach-O 64-bit dynamically linked shared library x86_64
/opt/local/lib/libcxx/libc++abi.dylib (for architecture i386):	Mach-O dynamically linked shared library i386

[ryandesign (Ryan Carsten Schmidt)]

Seems like you would at least want to enforce that if the universal variant of macports-libcxx is selected, then the universal variant of clang-11 must be selected (via the active_variants 1.1 portgroup), and similarly when the variant is not selected.

[kencu (Ken)]

it’s automatically done already at build time, so no need to complicate things up further

to elaborate… the files are copied out when macports-libcxx is built, so after that, whatever clang-11 is is no longer relevant

[kencu (Ken)]

unless you see some way this might fail with those sharp eyes of yours that I cannot see….

[kencu (Ken)]

hmm….

what would happen if a user had clang-11 installed +universal

and then tried to install macports-libcxx without the universal variant, building it from source rather than downloading the prebuilt binary for some reason (eg alternate prefix)?

Would macports base accept the installed clang-11 +universal as filling the build dependency for clang-11 (probably would I guess) and then copy in the universal libc++ dylibs from that?

I could see that pathway perhaps giving you an installed actual universal macports-libcxx that is registered as not being universal by base, if that works like that…

[barracuda156]

It is still broken #69189