[PATCH] D150013: [Clang] Respect `-L` options when compiling directly for AMDGPU

Tue May 9 10:33:17 PDT 2023

MaskRay added inline comments.

================
Comment at: clang/lib/Driver/ToolChains/AMDGPU.cpp:546
   addLinkerCompressDebugSectionsOption(getToolChain(), Args, CmdArgs);
   AddLinkerInputs(getToolChain(), Inputs, Args, CmdArgs, JA);
+  Args.AddAllArgs(CmdArgs, options::OPT_L);
----------------
jhuber6 wrote:
> yaxunl wrote:
> > jhuber6 wrote:
> > > yaxunl wrote:
> > > > AddLinkerInputs has code doing that, and it handles env var LIBRARY_PATH. However that code is disabled for AMDGPU because AMDGPU returns true for isCrossCompiling.
> > > > 
> > > > https://github.com/llvm/llvm-project/blob/main/clang/lib/Driver/ToolChains/CommonArgs.cpp#L236
> > > > 
> > > > It seems isCrossCompiling is solely for controlling whether to consume `-L`. If we want amdgpu toolchain to accept `-L`, we can simply let isCrossCompiling return false.
> > > Good catch, we could maybe set `isCrossCompiling` to false if targeted directly by the user, e.g. `--target=amdgcn-amd-amdhsa` vs `--offload-arch`.
> > That would be better. Thanks.
> It still is technically cross compiling, since we are building for a target that does not match the system's architecture. The original code that prevents passing `-L` was contributed by @MaskRay. I understand that we may not want to pass `LIBRARY_PATH` defines, but what's the rationale for not passing any `-L` options manually specified by the user?
The `LIBRARY_PATH` code had been there when I moved it in 2019. It'd be best not to rely on `LIBRARY_PATH`. I think that forwarding `-L` seems reasonable but I am not familiar with the amdgpu ecosystem..

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D150013/new/

https://reviews.llvm.org/D150013