[PATCH] D153737: [clang] __is_trivially_equality_comparable should return false for arrays

[Nikolas Klauser via Phabricator via cfe-commits]

philnik created this revision.
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When comparing two arrays, their pointers are compared instead of their elements, which menas that they are not trivially equality comparable


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D153737

Files:
  clang/lib/AST/Type.cpp
  clang/test/SemaCXX/type-traits.cpp


Index: clang/test/SemaCXX/type-traits.cpp
===================================================================
--- clang/test/SemaCXX/type-traits.cpp
+++ clang/test/SemaCXX/type-traits.cpp
@@ -3110,7 +3110,7 @@
 static_assert(!__is_trivially_equality_comparable(void), "");
 static_assert(__is_trivially_equality_comparable(int), "");
 static_assert(!__is_trivially_equality_comparable(int[]), "");
-static_assert(__is_trivially_equality_comparable(int[3]), "");
+static_assert(!__is_trivially_equality_comparable(int[3]), "");
 static_assert(!__is_trivially_equality_comparable(float), "");
 static_assert(!__is_trivially_equality_comparable(double), "");
 static_assert(!__is_trivially_equality_comparable(long double), "");
@@ -3134,6 +3134,13 @@
 };
 static_assert(__is_trivially_equality_comparable(TriviallyEqualityComparable), "");
 
+struct TriviallyEqualityComparableContainsArray {
+  int a[4];
+
+  bool operator==(const TriviallyEqualityComparableContainsArray&) const = default;
+};
+static_assert(__is_trivially_equality_comparable(TriviallyEqualityComparableContainsArray));
+
 struct TriviallyEqualityComparableNonTriviallyCopyable {
   TriviallyEqualityComparableNonTriviallyCopyable(const TriviallyEqualityComparableNonTriviallyCopyable&);
   ~TriviallyEqualityComparableNonTriviallyCopyable();
Index: clang/lib/AST/Type.cpp
===================================================================
--- clang/lib/AST/Type.cpp
+++ clang/lib/AST/Type.cpp
@@ -2684,7 +2684,7 @@
     const ASTContext &Context) const {
   QualType CanonicalType = getCanonicalType();
   if (CanonicalType->isIncompleteType() || CanonicalType->isDependentType() ||
-      CanonicalType->isEnumeralType())
+      CanonicalType->isEnumeralType() || CanonicalType->isArrayType())
     return false;
 
   if (const auto *RD = CanonicalType->getAsCXXRecordDecl()) {


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