dra27
commented
2 years ago Sorry for ignoring this one too! The problem is definitely reported by flexdll - I presume that was with declspec(dllimport) in the .hpp, rather than the .cpp file? Do any of the other plugins have to call that precise function?
I'm working on porting the Binary Analysis Platform / BAP to Windows.
Unless I am misunderstanding, the mingw64 chain , >=OCaml 4.12.1, and >=Binutils 2.36 should no longer be experiencing runtime plugin/dll relocation failures with RELOC_REL32.
Using MSYS2's UCRT shell/toolchain (I have this same issue in Cygwin, too.), MinGW GCC 11.2, OCaml 4.13.1 + flambda, and the latest git source of flexdll.
However, the LLVM-backend plugin for BAP is erroring out here. If I get flexlink to pass --default-image-base-low when linking the main executable and the breaking plugin, it's fine. Decorating the symbol as a dllimport, in the plugin code, didn't appear to make a difference.
No other plugins seem to have this issue, even when they are left with a high base address & the executable is low.
Failed to load plugin "bap-plugin-llvm": Failed to load bap_llvm: error loading shared library: Dynlink.Error (Dynlink.Cannot_open_dll "(Failure\n \"flexdll error: cannot relocate _ZN3bap21register_disassemblerENSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEESt10shared_ptrINS_14disasm_factoryEE RELOC_REL32, target is too far: FFFFFFFCCE4E7D5B FFFFFFFFCE4E7D5B\")")bap::register_disassembler(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::shared_ptr<bap::disasm_factory>)These are the instantiation of the register_disassembler function in the main executable: https://github.com/BinaryAnalysisPlatform/bap/blob/master/lib/bap_disasm/disasm.hpp https://github.com/BinaryAnalysisPlatform/bap/blob/master/lib/bap_disasm/disasm.cpp
And this is the plugin's usage of it: https://github.com/BinaryAnalysisPlatform/bap/blob/master/lib/bap_llvm/llvm_disasm.cpp
I'll be honest and say that I'm only guessing that this problem lies with FlexDLL, but it could be in OCaml itself, BAP's source code, MinGW, etc.
If needed, I can provide a way to reproduce this; however, it's unfortunately not a quick process, and will require manual steps in the build process. At that, I could also provide the virtual machine image or the msys64 folder.