[all-commits] [llvm/llvm-project] 5a88df: [Clang] Only define `wchar_size` module flag if no...

Wed Mar 4 14:14:11 PST 2026

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 5a88dffc40d2ae422127deb75412b8f4dff20d8b
      https://github.com/llvm/llvm-project/commit/5a88dffc40d2ae422127deb75412b8f4dff20d8b
  Author: Joseph Huber <huberjn at outlook.com>
  Date:   2026-03-04 (Wed, 04 Mar 2026)

  Changed paths:
    M clang/lib/CodeGen/CodeGenModule.cpp
    M clang/test/CodeGen/AArch64/cpu-supports-target.c
    M clang/test/CodeGen/AArch64/cpu-supports.c
    M clang/test/CodeGen/AArch64/fmv-detection.c
    M clang/test/CodeGen/AArch64/fmv-explicit-priority.c
    M clang/test/CodeGen/AArch64/fmv-mix-explicit-implicit-default.c
    M clang/test/CodeGen/AArch64/fmv-resolver-emission.c
    M clang/test/CodeGen/AArch64/fmv-unreachable-version.c
    M clang/test/CodeGen/AArch64/ls64.c
    M clang/test/CodeGen/AArch64/mixed-target-attributes.c
    M clang/test/CodeGen/AArch64/targetattr.c
    M clang/test/CodeGen/LoongArch/targetattr-la32.c
    M clang/test/CodeGen/LoongArch/targetattr-la64.c
    M clang/test/CodeGen/RISCV/ntlh-intrinsics/riscv32-zihintntl.c
    M clang/test/CodeGen/RISCV/rvv-intrinsics-handcrafted/vlenb.c
    M clang/test/CodeGen/SystemZ/vec-abi-gnuattr-00.c
    M clang/test/CodeGen/SystemZ/vec-abi-gnuattr-01.c
    M clang/test/CodeGen/SystemZ/vec-abi-gnuattr-03b.c
    M clang/test/CodeGen/SystemZ/vec-abi-gnuattr-04.c
    M clang/test/CodeGen/SystemZ/vec-abi-gnuattr-05.c
    M clang/test/CodeGen/SystemZ/vec-abi-gnuattr-06.c
    M clang/test/CodeGen/SystemZ/vec-abi-gnuattr-07.c
    M clang/test/CodeGen/SystemZ/vec-abi-gnuattr-08.c
    M clang/test/CodeGen/SystemZ/vec-abi-gnuattr-08b.c
    M clang/test/CodeGen/SystemZ/vec-abi-gnuattr-09.c
    M clang/test/CodeGen/SystemZ/vec-abi-gnuattr-09b.c
    M clang/test/CodeGen/SystemZ/vec-abi-gnuattr-11.c
    M clang/test/CodeGen/SystemZ/vec-abi-gnuattr-12.c
    M clang/test/CodeGen/SystemZ/vec-abi-gnuattr-13.c
    M clang/test/CodeGen/SystemZ/vec-abi-gnuattr-14.c
    M clang/test/CodeGen/SystemZ/vec-abi-gnuattr-15.c
    M clang/test/CodeGen/SystemZ/vec-abi-gnuattr-16.c
    M clang/test/CodeGen/SystemZ/vec-abi-gnuattr-17.c
    M clang/test/CodeGen/SystemZ/vec-abi-gnuattr-17b.c
    M clang/test/CodeGen/SystemZ/vec-abi-gnuattr-18.c
    M clang/test/CodeGen/SystemZ/vec-abi-gnuattr-19.c
    M clang/test/CodeGen/SystemZ/vec-abi-gnuattr-20.cpp
    M clang/test/CodeGen/SystemZ/vec-abi-gnuattr-21.c
    M clang/test/CodeGen/SystemZ/vec-abi-gnuattr-22.c
    M clang/test/CodeGen/SystemZ/vec-abi-gnuattr-23.c
    M clang/test/CodeGen/amdgpu-abi-version.c
    M clang/test/CodeGen/amdgpu-address-spaces.cpp
    M clang/test/CodeGen/arm-metadata.c
    M clang/test/CodeGen/asm-goto2.c
    M clang/test/CodeGen/attr-target-clones-aarch64.c
    M clang/test/CodeGen/attr-target-clones-riscv.c
    M clang/test/CodeGen/attr-target-version-riscv.c
    M clang/test/CodeGen/catch-implicit-integer-sign-changes-incdec.c
    M clang/test/CodeGen/linux-kernel-struct-union-initializer.c
    M clang/test/CodeGen/linux-kernel-struct-union-initializer2.c
    M clang/test/CodeGen/memcpy-inline-builtin.c
    M clang/test/CodeGen/nvptx_attributes.c
    M clang/test/CodeGen/ptrauth-module-flags.c
    M clang/test/CodeGen/sanitize-metadata-ignorelist.c
    M clang/test/CodeGen/sanitize-metadata-nosanitize.c
    M clang/test/CodeGen/sanitize-type-globals.cpp
    M clang/test/CodeGen/stack-protector-guard.c
    M clang/test/CodeGen/ubsan-function-sugared.cpp
    M clang/test/CodeGen/ubsan-function.cpp
    M clang/test/CodeGen/wasm-fp16.c
    M clang/test/CodeGen/wchar-size.c
    M clang/test/CodeGenCUDA/convergent.cu
    M clang/test/CodeGenCXX/attr-target-clones-aarch64.cpp
    M clang/test/CodeGenCXX/attr-target-clones-riscv.cpp
    M clang/test/CodeGenCXX/attr-target-version-riscv.cpp
    M clang/test/CodeGenCXX/attr-target-version.cpp
    M clang/test/CodeGenCXX/builtin-invoke.cpp
    M clang/test/CodeGenCXX/dynamic-cast-address-space.cpp
    M clang/test/CodeGenCXX/fmv-namespace.cpp
    M clang/test/CodeGenCXX/pfp-memcpy.cpp
    M clang/test/CodeGenHIP/default-attributes.hip
    M clang/test/CodeGenHIP/hip_weak_alias.cpp
    M clang/test/CodeGenHIP/sanitize-undefined-null.hip
    M clang/test/CodeGenOpenCL/amdgpu-cluster-dims.cl
    M clang/test/CodeGenOpenCL/amdgpu-enqueue-kernel.cl
    M clang/test/CodeGenOpenCL/builtins-amdgcn-gws-insts.cl
    M clang/test/CodeGenOpenCL/cl20-device-side-enqueue-attributes.cl
    M clang/test/CodeGenSYCL/function-attrs.cpp
    M clang/test/DebugInfo/CXX/ms-novtable.cpp
    M clang/test/OpenMP/amdgcn_target_global_constructor.cpp
    M clang/test/OpenMP/amdgcn_weak_alias.c
    M clang/test/OpenMP/amdgcn_weak_alias.cpp
    M clang/test/OpenMP/irbuilder_safelen.cpp
    M clang/test/OpenMP/irbuilder_safelen_order_concurrent.cpp
    M clang/test/OpenMP/irbuilder_simd_aligned.cpp
    M clang/test/OpenMP/irbuilder_simdlen.cpp
    M clang/test/OpenMP/irbuilder_simdlen_safelen.cpp
    M clang/test/OpenMP/nvptx_weak_alias.c
    M clang/test/OpenMP/tile_codegen_tile_for.cpp
    M clang/test/utils/update_cc_test_checks/Inputs/annotations.c.expected
    M clang/test/utils/update_cc_test_checks/Inputs/generated-funcs.c.generated.all.expected
    M clang/test/utils/update_cc_test_checks/Inputs/generated-funcs.c.generated.expected
    M clang/test/utils/update_cc_test_checks/Inputs/generated-funcs.c.no-generated.all.expected
    M clang/test/utils/update_cc_test_checks/Inputs/generated-funcs.c.no-generated.expected
    M clang/test/utils/update_cc_test_checks/Inputs/resolve-tmp-conflict.cpp.expected
    M clang/test/utils/update_cc_test_checks/check-globals.test
    M llvm/include/llvm/TargetParser/Triple.h
    M llvm/lib/Analysis/TargetLibraryInfo.cpp
    M llvm/lib/Target/ARM/ARMAsmPrinter.cpp
    M llvm/lib/TargetParser/Triple.cpp
    M llvm/test/Transforms/InstCombine/wcslen-4.ll
    M llvm/unittests/TargetParser/TripleTest.cpp

  Log Message:
  -----------
  [Clang] Only define `wchar_size` module flag if non-standard (#184668)

Summary:
This PR simply changes the behavior of the `wchar_size` flag. Currently,
we emit this in all cases for all targets. This causes problems during
LLVM-IR linking, specifically because this would vary between Linux and
Windows in unintuitive ways. Now we have an llvm::Triple helper to
determine the size from the known values. The module flag will only be
emitted if these do not match (indicating a non-standard environment).

In addition to fixing AMDGCN bitcode linking, this also means we don't
need to bloat *every* IR module compiled by clang with this flag. The
changed tests reflects this, one less unnecessary piece of metadata.

To unsubscribe from these emails, change your notification settings at https://github.com/llvm/llvm-project/settings/notifications