Author: Robert Dazi Date: 2025-01-27T12:43:37+01:00 New Revision: ddbfe6f7d2075a828fa9e8e5f5734bf881cda13a
URL: https://github.com/llvm/llvm-project/commit/ddbfe6f7d2075a828fa9e8e5f5734bf881cda13a DIFF: https://github.com/llvm/llvm-project/commit/ddbfe6f7d2075a828fa9e8e5f5734bf881cda13a.diff LOG: [Sema] Fix __array_rank instantiation (#124491) The type being queried was left as a template type parameter, making the whole expression as dependent and thus not eligible to static_assert. Fixes #123498 Co-authored-by: v01dxyz <v01d...@v01d.xyz> Co-authored-by: cor3ntin <corentinja...@gmail.com> Added: clang/test/SemaCXX/array-type-trait-with-template.cpp Modified: clang/docs/ReleaseNotes.rst clang/include/clang/AST/ExprCXX.h clang/lib/Sema/TreeTransform.h Removed: ################################################################################ diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index b63bd366cfe884..c60565a568234a 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -1002,6 +1002,8 @@ Bug Fixes to C++ Support - Fixed assertions or false compiler diagnostics in the case of C++ modules for lambda functions or inline friend functions defined inside templates (#GH122493). - Clang now rejects declaring an alias template with the same name as its template parameter. (#GH123423) +- Fix type of expression when calling a template which returns an ``__array_rank`` querying a type depending on a + template parameter. Now, such expression can be used with ``static_assert`` and ``constexpr``. (#GH123498) - Correctly determine the implicit constexprness of lambdas in dependent contexts. (#GH97958) (#GH114234) Bug Fixes to AST Handling diff --git a/clang/include/clang/AST/ExprCXX.h b/clang/include/clang/AST/ExprCXX.h index aa10945addf78f..2a130bc6da79a0 100644 --- a/clang/include/clang/AST/ExprCXX.h +++ b/clang/include/clang/AST/ExprCXX.h @@ -2847,8 +2847,8 @@ class TypeTraitExpr final /// /// Example: /// \code -/// __array_rank(int[10][20]) == 2 -/// __array_extent(int, 1) == 20 +/// __array_rank(int[10][20]) == 2 +/// __array_extent(int[10][20], 1) == 20 /// \endcode class ArrayTypeTraitExpr : public Expr { /// The trait. An ArrayTypeTrait enum in MSVC compat unsigned. diff --git a/clang/lib/Sema/TreeTransform.h b/clang/lib/Sema/TreeTransform.h index 12680843a434a0..f04adf7fdf8ad2 100644 --- a/clang/lib/Sema/TreeTransform.h +++ b/clang/lib/Sema/TreeTransform.h @@ -14947,9 +14947,6 @@ TreeTransform<Derived>::TransformArrayTypeTraitExpr(ArrayTypeTraitExpr *E) { SubExpr = getDerived().TransformExpr(E->getDimensionExpression()); if (SubExpr.isInvalid()) return ExprError(); - - if (!getDerived().AlwaysRebuild() && SubExpr.get() == E->getDimensionExpression()) - return E; } return getDerived().RebuildArrayTypeTrait(E->getTrait(), E->getBeginLoc(), T, diff --git a/clang/test/SemaCXX/array-type-trait-with-template.cpp b/clang/test/SemaCXX/array-type-trait-with-template.cpp new file mode 100644 index 00000000000000..942714ec5d55a5 --- /dev/null +++ b/clang/test/SemaCXX/array-type-trait-with-template.cpp @@ -0,0 +1,129 @@ +// RUN: %clang_cc1 -fsyntax-only %s +// RUN: %clang_cc1 -fsyntax-only -std=c++20 -DWITH_AUTO_FUNCTION_PARAMETER=1 %s + +// When __array_rank is used with a template type parameter, this test +// ensures clang considers the final expression could be used with +// static_assert/constexpr. +// +// Although array_extent was handled well, we add it as a precaution. + +template <typename T> +using remove_reference_t = __remove_reference_t(T); + +template <typename T, int N> +constexpr int array_rank(T (&lhs)[N]) { + return __array_rank(T[N]); +} + +template <int I, typename T, int N> + constexpr int array_extent(T (&lhs)[N]) { + return __array_extent(T[N], I); +} + +template <typename T> +struct Rank { + using ArrayT = remove_reference_t<T>; + + template <int N> + static constexpr int call(ArrayT (&lhs)[N]) { + return __array_rank(ArrayT[N]); + } +}; + +template <typename T> +struct Extent { + using ArrayT = remove_reference_t<T>; + + template <int I, int N> + static constexpr int call(ArrayT (&lhs)[N]) { + return __array_extent(ArrayT[N], I); + } +}; + +#ifdef WITH_AUTO_FUNCTION_PARAMETER +template <int N> +constexpr int array_rank_auto(auto (&lhs)[N]) { + return __array_rank(remove_reference_t<decltype(lhs[0])>[N]); +} + +template <int I, int N> +constexpr int array_extent_auto(auto (&lhs)[N]) { + return __array_extent(remove_reference_t<decltype(lhs[0])>[N], I); +} +#endif + +template <int N> +constexpr int array_rank_int(const int (&lhs)[N]) { + return __array_rank(const int[N]); +} + +template <int I, int N> +constexpr int array_extent_int(const int (&lhs)[N]) { + return __array_extent(const int[N], I); +} + +template <int M, int N> +constexpr int array_rank_int(const int (&lhs)[M][N]) { + return __array_rank(const int[M][N]); +} + +template <int I, int M, int N> +constexpr int array_extent_int(const int (&lhs)[M][N]) { + return __array_extent(const int[M][N], I); +} + +int main() { + constexpr int vec[] = {0, 1, 2, 1}; + constexpr int mat[4][4] = { + {1, 0, 0, 0}, + {0, 1, 0, 0}, + {0, 0, 1, 0}, + {0, 0, 0, 1} + }; + +#define ATT_TESTS_WITH_ASSERT(ATT_ASSERT) \ + { ATT_ASSERT(RANK(vec) == 1); } \ + { ATT_ASSERT(RANK(mat) == 2); } \ + { ATT_ASSERT(EXTENT(vec, 0) == 4); } \ + { ATT_ASSERT(EXTENT(vec, 1) == 0); } \ + { ATT_ASSERT(EXTENT(mat, 1) == 4); } + +#define ATT_TESTS() \ + ATT_TESTS_WITH_ASSERT( constexpr bool cst = ) \ + ATT_TESTS_WITH_ASSERT( (void) ) \ + ATT_TESTS_WITH_ASSERT( static_assert ) + + { +#define RANK(lhs) array_rank(lhs) +#define EXTENT(lhs, i) array_extent<i>(lhs) + ATT_TESTS(); +#undef RANK +#undef EXTENT + } + + { +#define RANK(lhs) Rank<decltype(lhs[0])>::call(lhs) +#define EXTENT(lhs, i) Extent<decltype(lhs[0])>::call<i>(lhs) + ATT_TESTS(); +#undef RANK +#undef EXTENT + } + +#ifdef WITH_AUTO_FUNCTION_PARAMETER + { +#define RANK(lhs) array_rank_auto(lhs) +#define EXTENT(lhs, i) array_extent_auto<i>(lhs) + ATT_TESTS(); +#undef RANK +#undef EXTENT + } +#endif + + { +#define RANK(lhs) array_rank_int(lhs) +#define EXTENT(lhs, i) array_extent_int<i>(lhs) + ATT_TESTS(); +#undef RANK +#undef EXTENT + } +} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
