In https://github.com/ffi/ffi/actions/runs/14237177527/job/39910781515?pr=1144, I see CI failing:

 configure.ac:219: error: possibly undefined macro: LT_SYS_SYMBOL_USCORE
      If this token and others are legitimate, please use m4_pattern_allow.
      See the Autoconf documentation.
autoreconf: error: /usr/bin/autoconf failed with exit status: 1

libffi/libffi#210 suggests libltdl-dev needs to be installed. I see this in the Rakefile, but not in these CI jobs.

I'm seeing two main types of errors now:

1. macOS 13 ./spec/ffi/number_spec.rb: https://github.com/ffi/ffi/actions/runs/14246629958/job/39929485426?pr=1144 -> Possibly due to the libffi change here: Repair struct result on x86 Darwin (OS X) libffi/libffi#876
2. Missing fiddle in ruby-head: https://github.com/ffi/ffi/actions/runs/14246629958/job/39929485558?pr=1144 -> Gemfile: depend on fiddle to avoid a Ruby warning #1119

I reproduced this on a macOS 13 system. It seems that libffi/libffi#848 is the culprit.

libffi/libffi#889 fixes this. Updating libffi to fe203ffbb2bd7f93a86013d341aa767a406150bc fixes the issue.

This update is essentially passing CI. There are some failures:

1. I think the macOS jobs that are failing with --enable-system-libffi because libffi v3.4.7 is used. This is why fe203ffbb2bd7f93a86013d341aa767a406150bc is needed (https://github.com/ffi/ffi/actions/runs/14248309635/job/39965003682?pr=1144).
2. The fiddle requirement for ruby-head is also a known issue (https://github.com/ffi/ffi/actions/runs/14248309635/job/39965003760?pr=1144).
3. It looks like the multiarch test uses centos:latest, but that image is not long available (https://github.com/ffi/ffi/actions/runs/14248309635/job/39965148130?pr=1144). Maybe it's time to update that to centos:8 or some other RHEL-based image?

Compare the results of this to the latest run on master: https://github.com/ffi/ffi/actions/runs/14211954501

Thank you for helping! I'll try to push a new release the next days.

I'll try to push a new release the next days.

@larskanis just a gentle poke on this. There are many ruby gems that have ffi as a dependency and this issue means they can't be installed on newer macs or on new environments, this impacts new starters & attempts to upgrade ruby locally, so the number of people impacts by this is going to go up day by day.

For anyone else struggling with this, I eventually found a workaround, but it takes a tediously long time.

1. Install LLVM 16 (which includes Clang 16): (this takes quite a while)

brew install llvm@16

2. Temporarily use this version for your current terminal session:

export PATH="$(brew --prefix llvm@16)/bin:$PATH"
export LDFLAGS="-L$(brew --prefix llvm@16)/lib"
export CPPFLAGS="-I$(brew --prefix llvm@16)/include"
export CC="$(brew --prefix llvm@16)/bin/clang"
export CXX="$(brew --prefix llvm@16)/bin/clang++"

3. Verify the clang version:

clang --version

This should now show version 16.x.x.
4. Install the gems

bundle install

I'm surprised you ran into issues with LLVM 16; ffi v1.17.1 works fine for me.

I thought LLVM 17 had issues, though.

In any case, it looks like the 1.17.2 tag was created. Now we await a push of the gem to RubyGems. I see https://github.com/ffi/ffi/actions/runs/14454729540 has built the v1.17.2 tag.

I'm surprised you ran into issues with LLVM 16

I have no problems with LLVM 16. I have problems with clang 17 (which I believe most modern apple products will now be using) so I had to manually install LLVM 16 (as per the described steps) in order to get clang 16 to install locally, and then use that to install the gem.