Ftarget fails to generate when fuzzing Nginx about aflgo HOT 2 CLOSED

Thanks for your issue report!

The problem here is that disabling the compiler option -flto will disable the GOLD plugin for LLVM (http://llvm.org/docs/GoldPlugin.html). This in turn will disable some functionality in afl-llvm-pass.so.cc.

During compilation,

• If the linker (CCLD) complains that you should run ranlib, make sure that libLTO.so and LLVMgold.so (from building LLVM with Gold) can be found in /usr/lib/bfd-plugins
• If the compiler crashes, there is some problem with LLVM not supporting our instrumentation (afl-llvm-pass.so.cc:540-577). LLVM has changed the instrumentation-API very often :(
  -> Check LLVM-version, fix problem, and prepare pull request.

If you have problems setting up the most recent version of LLVM with GOLD, we suggest to build and use the Docker image which is available at: https://github.com/aflgo/oss-fuzz/blob/master/infra/base-images/base-clang/.

from aflgo.

Thank you for your reply.

However Nginx does not compile with -flto. It reports that the format of nginx.o cannot be recognized during linking.

from aflgo.