zeromq 4.3.1

[aimileus]

Created with brew bump-formula-pr.

[bluca]

Thanks!

[scpeters]

The libzmq.pc pkg-config file has changed in 4.3.1 (I think from zeromq/libzmq#3336) to have the following line:

Requires.private:  libunwind

but there is no libunwind.pc file anywhere that I can find on macOS (I've checked high sierra and mojave), so downstream software that uses pkg-config to find zeromq fails to find it:

Package libunwind was not found in the pkg-config search path.
Perhaps you should add the directory containing `libunwind.pc'
to the PKG_CONFIG_PATH environment variable
Package 'libunwind', required by 'libzmq', not found

[scpeters]

Maybe we can add a test invocation of pkg-config to the zeromq formula

[bluca]

Upstream's libunwind ships the pkgconfig file, so either fix the brew formula that builds it to install it, or disable libunwind in this formula
https://github.com/libunwind/libunwind/blob/master/src/unwind/libunwind.pc.in

[scpeters]

libunwind functionality is provided by macOS; this might be a time to add a libunwind.pc to https://github.com/Homebrew/brew/tree/master/Library/Homebrew/os/mac/pkgconfig

[scpeters]

I'm proposing to add libunwind.pc files to homebrew/brew in Homebrew/brew#5539

[bluca]

Ok. Note that if it's urgent you can disable libunwind manually with --disable-libunwind

[EricLambrecht]

@bluca Which command is supposed to be run with --disable-libunwind exactly?

[bluca]

that's for ./configure

[bluca]

Also I see the libunwind flags are set manually via ENV - it would be sufficient to remove those so that autoconf doesn't find it

[bluca]

There's something I don't quite follow: the Requires.private are filled by autoconf ONLY if the dependency is found VIA pkg-config - in other words, if there's no libunwind.pc, there won't be a Requires.private: libunwind.
If I understand correctly there's no libunwind.pc at the moment - so how exactly is it being found at build time?
As the autoconf file currently is, unless libunwind.pc is found, it won't even build with libunwind - there's no fallback at all.

[scpeters]

Specifying the flags seems to make the configure script think that a .pc file exists.

[scpeters]

Ok, I just submitted a PR to disable libunwind in the zeromq formula until we figure this out.

[bluca]

That's really strange, it's the pkgconfig m4 macro that's used and that should just fail if the pc is not found, is homebrew shipping a custom one?