https://github.com/mugiwaraluffy56 updated https://github.com/llvm/llvm-project/pull/178656
>From 3498a11e06c1f55f142b3fbb6803ebde37cf3236 Mon Sep 17 00:00:00 2001 From: mugiwaraluffy56 <[email protected]> Date: Thu, 29 Jan 2026 19:22:00 +0530 Subject: [PATCH] [clang-tidy] Allow type-generic builtins in pro-type-vararg check Add __builtin_clzg, __builtin_ctzg, __builtin_popcountg, and __builtin_bswapg to the allowed variadics list. These type-generic builtins are declared as variadic to accept any integer type, but they are not C-style vararg functions and should not trigger the hicpp-vararg / cppcoreguidelines-pro-type-vararg warning. Fixes #178629 --- .../clang-tidy/cppcoreguidelines/ProTypeVarargCheck.cpp | 8 ++++++++ clang-tools-extra/docs/ReleaseNotes.rst | 6 ++++++ .../checkers/cppcoreguidelines/pro-type-vararg.cpp | 6 ++++++ 3 files changed, 20 insertions(+) diff --git a/clang-tools-extra/clang-tidy/cppcoreguidelines/ProTypeVarargCheck.cpp b/clang-tools-extra/clang-tidy/cppcoreguidelines/ProTypeVarargCheck.cpp index d5ff4af84b0b7..ac1be20f91bdf 100644 --- a/clang-tools-extra/clang-tidy/cppcoreguidelines/ProTypeVarargCheck.cpp +++ b/clang-tools-extra/clang-tidy/cppcoreguidelines/ProTypeVarargCheck.cpp @@ -178,6 +178,14 @@ void ProTypeVarargCheck::check(const MatchFinder::MatchResult &Result) { if (const auto *Matched = Result.Nodes.getNodeAs<CallExpr>("callvararg")) { if (hasSingleVariadicArgumentWithValue(Matched, 0)) return; + + // Skip builtins with custom type checking - they use variadics as an + // implementation detail to accept multiple types, not for C-style varargs. + if (const auto *FD = Matched->getDirectCallee()) + if (const unsigned BuiltinID = FD->getBuiltinID(); + BuiltinID && Result.Context->BuiltinInfo.hasCustomTypechecking(BuiltinID)) + return; + diag(Matched->getExprLoc(), "do not call c-style vararg functions"); } diff --git a/clang-tools-extra/docs/ReleaseNotes.rst b/clang-tools-extra/docs/ReleaseNotes.rst index 754880bd1a381..082117452b2ff 100644 --- a/clang-tools-extra/docs/ReleaseNotes.rst +++ b/clang-tools-extra/docs/ReleaseNotes.rst @@ -136,6 +136,12 @@ Changes in existing checks the invalidating function in the warning message when a custom invalidation function is used (via the `InvalidationFunctions` option). +- Improved :doc:`cppcoreguidelines-pro-type-vararg + <clang-tidy/checks/cppcoreguidelines/pro-type-vararg>` check by no longer + warning on builtins with custom type checking (e.g., type-generic builtins + like ``__builtin_clzg``) that use variadic declarations as an implementation + detail. + - Improved :doc:`llvm-use-ranges <clang-tidy/checks/llvm/use-ranges>` check by adding support for the following algorithms: ``std::accumulate``, ``std::replace_copy``, and diff --git a/clang-tools-extra/test/clang-tidy/checkers/cppcoreguidelines/pro-type-vararg.cpp b/clang-tools-extra/test/clang-tidy/checkers/cppcoreguidelines/pro-type-vararg.cpp index 3f73d1de333f4..1a5a5fb7dd93c 100644 --- a/clang-tools-extra/test/clang-tidy/checkers/cppcoreguidelines/pro-type-vararg.cpp +++ b/clang-tools-extra/test/clang-tidy/checkers/cppcoreguidelines/pro-type-vararg.cpp @@ -57,6 +57,12 @@ void ignoredBuiltinsTest(void *ptr) { (void)__builtin_fpclassify(0, 0, 0, 0, 0, 0.f); (void)__builtin_isinf_sign(0.f); (void)__builtin_prefetch(nullptr); + + // GH#178629: Type-generic builtins should not warn. + (void)__builtin_clzg(1u); + (void)__builtin_ctzg(1u); + (void)__builtin_popcountg(1u); + (void)__builtin_bswapg(1u); } // Some implementations of __builtin_va_list and __builtin_ms_va_list desugared _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
