phosek added a comment. In D110663#3029147 <https://reviews.llvm.org/D110663#3029147>, @MaskRay wrote:
> In D110663#3029146 <https://reviews.llvm.org/D110663#3029146>, @phosek wrote: > >> In D110663#3029124 <https://reviews.llvm.org/D110663#3029124>, @MaskRay >> wrote: >> >>> In D110663#3029088 <https://reviews.llvm.org/D110663#3029088>, @phosek >>> wrote: >>> >>>> The reason I removed this behavior in D101194 >>>> <https://reviews.llvm.org/D101194>, aside from extra overhead introduced >>>> by the extra checks, is that we've seen cases where people would have >>>> both paths on their system which lead to difficult to diagnose issues >>>> where Clang would pick up a library different from the one they expected. >>>> I'd therefore prefer supporting only a single spelling of the triple that >>>> could be configured, and making sure that Clang build on Debian uses the >>>> right configuration. >>> >>> The problem is that when LLVM_DEFAULT_TARGET_TRIPLE is "x86_64-linux-gnu" >>> (no vendor part), CMake respects it (instead of adding `unknown`) and >>> installs files to `lib/clang/14.0.0/x86_64-linux-gnu/`. >>> Currently clang driver only inspects the normalized >>> `lib/clang/14.0.0/x86_64-unknown-linux-gnu/` and cannot find it. >> >> I ran into this issue the past and the solution I considered would be to >> modify the CMake build of runtimes to query Clang for the triple (using >> `-dumpmachine`) and use that instead of `LLVM_DEFAULT_TARGET_TRIPLE`. I >> still think that change would be desirable for consistency and would be >> happy to implement it. > > If the host compiler is GCC (`gcc -dumpmachine` => `x86_64-linux-gnu` on > Debian amd64), how to query Clang for the triple? You mean when you build runtimes with the host compiler and then use them with Clang (i.e. by using `-DLLVM_ENABLE_PROJECTS="clang;lld;libcx"`)? This has been discussed several times on llvm-dev in the past, ideally nobody should be using this mode because there's no guarantee that the host compiler is ABI compatible with Clang. Unfortunately, I believe that some projects still build that way and it might take a while to migrate them to another approach. > My previous comment has been edited. I believe by making Debian derivatives > stick with `*-linux-gnu`, we can actually remove more code from the driver. Can you elaborate on it? What solution do you have in mind? Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D110663/new/ https://reviews.llvm.org/D110663 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
