MaskRay wrote: Thanks for the comments.
The syntax `-Wa,--crel -Wa,--experimental-crel` (or `-Wa,--crel,--experimental-crel`) might seem cumbersome, it serves a purpose: * `-Wa,--experimental-crel`: no effect * `-Wa,--crel`: driver error. Make sure users acknowledge the non-standard status. * `-Wa,--crel,--experimental-crel`: CREL As CREL adoption grows within the ecosystem, it has the potential to become a de-facto standard, similar to `SHF_EXCLUDE`. Once that happens, the `--experimental-crel` flag can be deprecated and eventually removed. This approahc parallels the strategy used for [`-enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang`](https://reviews.llvm.org/D125142), albeit a nicer name. --- I can split this PR into 5 components. * llvm-mc * clang driver * yaml2obj/obj2yaml * llvm-readobj * llvm-objdump The assembler testing might look bare-bone without llvm-readobj support. --- While ELF allows extension space for processor/OS/application-specific section types, using them introduces challenges since we want linker errors when SHT_CREL is unsupported (see `isKnownSpecificSectionType` in #85173): * [SHT_LOUSER,SHT_HIUSER]: Not applicable as static relocation sections do not have the SHF_ALLOC flag. * [SHT_LOOS,SHT_HIOS]: Requires annoying `SHF_OS_NONCONFORMING`. We want psABI documents to be willing to accept CREL when toolchain becomes ready, especially if their relocatable files are huge due to linker relaxation (e.g. RISC-V, LoongArch), we want to avoid GNUism / LLVMism. * [SHT_LOPROC,SHT_HIPROC]: Processor-specific and not applicable. We will unlikely change the format. I avoid the name `SHT_EXP_*` because the renaming would cause unnecessary churn. We also don't want to support two section type codes, because testing would be unnecessarily complex. Solaris-specific SHF_ORDERED and SHF_EXCLUDE, without a SunOS/Solaris name infix/prefix/suffix, make them into glibc elf.h. `SHF_EXCLUDE` gets picked due to its linker semantics but `SHF_ORDERED` is never used. A generic name `SHT_CREL` might not be fundamentally different from `SHF_ORDERED`. https://github.com/llvm/llvm-project/pull/91280 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
