When using android/clang, we cannot build elfhack tool. Because build/unix/elfhack/inject/Makefile.in removes clang's options unfortunately by $(filter ..) from CFLAGS. 0:10.71 In file included from /mozilla/objdir-android/build/unix/elfhack/inject/arm.c:5: 0:10.71 In file included from /home/makoto/bin/android-ndk-r15b/toolchains/llvm/prebuilt/linux-x86_64/lib64/clang/5.0.300080/include/stdint.h:63: 0:10.71 In file included from /usr/include/stdint.h:25: 0:10.71 /usr/include/features.h:364:12: fatal error: 'sys/cdefs.h' file not found 0:10.71 # include <sys/cdefs.h> 0:10.71 ^~~~~~~~~~~~~ When resolving this build error, elfhack throws assertion for libplugin-container.so that is generated by clang. 0:04.64 elfhack: /mozilla/mobile/build/unix/elfhack/elf.cpp:264: Elf::Elf(std::ifstream &): Assertion `segment->getFileSize() == phdr.p_filesz - gold_adjustment' failed. 0:04.64 Traceback (most recent call last): 0:04.64 File "/mozilla/mobile/toolkit/mozapps/installer/packager.py", line 326, in <module> 0:04.64 main() 0:04.64 File "/mozilla/mobile/toolkit/mozapps/installer/packager.py", line 320, in main 0:04.64 copier.copy(args.destination) 0:04.64 File "/mozilla/mobile/python/mozbuild/mozpack/copier.py", line 399, in copy 0:04.64 copy_results.append((destfile, f.copy(destfile, skip_if_older))) 0:04.64 File "/mozilla/mobile/python/mozbuild/mozpack/files.py", line 287, in copy 0:04.64 elfhack(dest) 0:04.64 File "/mozilla/mobile/python/mozbuild/mozpack/executables.py", line 124, in elfhack 0:04.64 errors.fatal('Error executing ' + ' '.join(cmd)) 0:04.64 File "/mozilla/mobile/python/mozbuild/mozpack/errors.py", line 103, in fatal 0:04.64 self._handle(self.FATAL, msg) 0:04.64 File "/mozilla/mobile/python/mozbuild/mozpack/errors.py", line 98, in _handle 0:04.64 raise ErrorMessage(msg) 0:04.64 mozpack.errors.ErrorMessage: Error: Error executing /mozilla/objdir-android/build/unix/elfhack/elfhack ../../../dist/geckoview/lib/armeabi-v7a/libplugin-container.so

I think some of the elfhack fixes that have been done for lld over the past few months have fixed this as well. I no longer see the error messages from comment 0 when using --enable-elf-hack with local patches (none of which touch build/unix/elfhack/) and running `mach package`.