Author: Younan Zhang Date: 2025-03-27T19:40:02+08:00 New Revision: a9672515ce6b8b1bc6976ed1225f4fb4d53fa381
URL: https://github.com/llvm/llvm-project/commit/a9672515ce6b8b1bc6976ed1225f4fb4d53fa381 DIFF: https://github.com/llvm/llvm-project/commit/a9672515ce6b8b1bc6976ed1225f4fb4d53fa381.diff LOG: [Clang] Correct the DeclRefExpr's Type after the initializer gets instantiated (#133212) The instantiation of a VarDecl's initializer might be deferred until the variable is actually used. However, we were still building the DeclRefExpr with a type that could later be changed by the initializer's instantiation, which is incorrect when incomplete arrays are involved. Fixes #79750 Fixes #113936 Fixes #133047 Added: Modified: clang/docs/ReleaseNotes.rst clang/lib/Sema/SemaExpr.cpp clang/test/SemaCXX/cxx1y-variable-templates_top_level.cpp Removed: ################################################################################ diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index 04ec2cfef679c..fb94c0c183033 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -359,6 +359,7 @@ Bug Fixes to C++ Support - Fixed C++20 aggregate initialization rules being incorrectly applied in certain contexts. (#GH131320) - Clang was previously coalescing volatile writes to members of volatile base class subobjects. The issue has been addressed by propagating qualifiers during derived-to-base conversions in the AST. (#GH127824) +- Correctly propagates the instantiated array type to the ``DeclRefExpr`` that refers to it. (#GH79750), (#GH113936), (#GH133047) - Fixed a Clang regression in C++20 mode where unresolved dependent call expressions were created inside non-dependent contexts (#GH122892) - Clang now emits the ``-Wunused-variable`` warning when some structured bindings are unused and the ``[[maybe_unused]]`` attribute is not applied. (#GH125810) diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp index 3af6d6c23438f..0ccc19437827c 100644 --- a/clang/lib/Sema/SemaExpr.cpp +++ b/clang/lib/Sema/SemaExpr.cpp @@ -19849,6 +19849,12 @@ static void DoMarkVarDeclReferenced( SemaRef.InstantiateVariableDefinition(PointOfInstantiation, Var); }); + // The size of an incomplete array type can be updated by + // instantiating the initializer. The DeclRefExpr's type should be + // updated accordingly too, or users of it would be confused! + if (E) + SemaRef.getCompletedType(E); + // Re-set the member to trigger a recomputation of the dependence bits // for the expression. if (auto *DRE = dyn_cast_or_null<DeclRefExpr>(E)) diff --git a/clang/test/SemaCXX/cxx1y-variable-templates_top_level.cpp b/clang/test/SemaCXX/cxx1y-variable-templates_top_level.cpp index da1678ec68627..6fc2032ee7fb4 100644 --- a/clang/test/SemaCXX/cxx1y-variable-templates_top_level.cpp +++ b/clang/test/SemaCXX/cxx1y-variable-templates_top_level.cpp @@ -467,3 +467,29 @@ namespace VexingParse { template <typename> int var; // expected-note {{declared here}} int x(var); // expected-error {{use of variable template 'var' requires template arguments}} } + +#ifndef PRECXX11 + +namespace GH79750 { + +enum class Values { A }; + +template<typename E> +constexpr Values values[] = {E::A}; + +constexpr auto r = values<Values>[0] == Values::A; + +} + +namespace GH113956 { + +template <class T, T... VALUES> +struct C { + static constexpr T VALUEARRAY[] = {VALUES...}; +}; + +static_assert(C<int, 0,1,2,3,4>::VALUEARRAY[3] == 3, ""); +static_assert(C<int, 0,1,2,3,4>::VALUEARRAY[0] == 0, ""); + +} +#endif _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
