failed to build libfaketime 0.9.12 on macos arm runners

[chenrui333]

👋 seeing the following build failure when building 0.9.12 on macos arm runners

   ==> make PREFIX=/opt/homebrew/Cellar/libfaketime/0.9.12 install
  /Applications/Xcode.app/Contents/Developer/usr/bin/make -f Makefile.OSX -C src install
  clang -o libfaketime.1.dylib -DFAKE_SLEEP -DFAKE_INTERNAL_CALLS -DPREFIX='"'/opt/homebrew/Cellar/libfaketime/0.9.12'"'  -DMACOS_DYLD_INTERPOSE -DFAKE_SETTIME -arch arm64e -arch arm64 -fptrauth-calls -fptrauth-returns  -dynamiclib -current_version 0.9.12 -compatibility_version 0.7 -install_name /opt/homebrew/Cellar/libfaketime/0.9.12/lib/faketime/libfaketime.1.dylib libfaketime.c
  clang -o faketime -DFAKE_SLEEP -DFAKE_INTERNAL_CALLS -DPREFIX='"'/opt/homebrew/Cellar/libfaketime/0.9.12'"'  -DMACOS_DYLD_INTERPOSE -DFAKE_SETTIME -arch arm64e -arch arm64 -fptrauth-calls -fptrauth-returns  faketime.c
  ld: PAC signed pointer not supported in base arm64: r_address=0x0, r_type=11, r_extern=1, r_pcrel=0, r_length=3 in '/private/tmp/faketime-bedcc4.o'
  clang: error: linker command failed with exit code 1 (use -v to see invocation)
  make[1]: *** [faketime] Error 1
  make[1]: *** Waiting for unfinished jobs....
  ld: PAC signed pointer not supported in base arm64: r_address=0xD8, r_type=11, r_extern=1, r_pcrel=0, r_length=3 in '/private/tmp/libfaketime-f086ed.o'
  clang: error: linker command failed with exit code 1 (use -v to see invocation)
  make[1]: *** [libfaketime.1.dylib] Error 1
  make: *** [install] Error 2

• libfaketime 0.9.12 Homebrew/homebrew-core#228050

[alebcay]

In case it helps, I am able to reproduce the same error outside of the Homebrew build environment (which is where the error above was encountered) on a macOS 15 (Sequoia) ARM64 machine.

One possible workaround is to invoke the compiler twice, building for arm64e with the extra flags for pointer auth, and then building for arm64 without those flags, and finally lipoing the output together into one binary (I have not tested the last part, trying to lipo together an arm64 and arm64e slice together).