Revert "[clang][AST] Check context of record in structural equivalence."

Revert commit 6b96b2a0bf65ff838d4dbf909a5120d4d1083e29 because Windows
test failure.

GitOrigin-RevId: 8804d08e9921b86eb96e993af5d753f63f3c8829
diff --git a/lib/AST/ASTStructuralEquivalence.cpp b/lib/AST/ASTStructuralEquivalence.cpp
index 7fd24e2..e85feb7 100644
--- a/lib/AST/ASTStructuralEquivalence.cpp
+++ b/lib/AST/ASTStructuralEquivalence.cpp
@@ -1347,42 +1347,6 @@
   return true;
 }
 
-/// Determine if context of a class is equivalent.
-static bool IsRecordContextStructurallyEquivalent(RecordDecl *D1,
-                                                  RecordDecl *D2) {
-  // The context should be completely equal, including anonymous and inline
-  // namespaces.
-  // We compare objects as part of full translation units, not subtrees of
-  // translation units.
-  DeclContext *DC1 = D1->getDeclContext()->getNonTransparentContext();
-  DeclContext *DC2 = D2->getDeclContext()->getNonTransparentContext();
-  while (true) {
-    // Special case: We allow a struct defined in a function to be equivalent
-    // with a similar struct defined outside of a function.
-    if ((DC1->isFunctionOrMethod() && DC2->isTranslationUnit()) ||
-        (DC2->isFunctionOrMethod() && DC1->isTranslationUnit()))
-      return true;
-
-    if (DC1->getDeclKind() != DC2->getDeclKind())
-      return false;
-    if (DC1->isTranslationUnit())
-      break;
-    if (DC1->isInlineNamespace() != DC2->isInlineNamespace())
-      return false;
-    if (const auto *ND1 = dyn_cast<NamedDecl>(DC1)) {
-      const auto *ND2 = cast<NamedDecl>(DC2);
-      if (!DC1->isInlineNamespace() &&
-          !IsStructurallyEquivalent(ND1->getIdentifier(), ND2->getIdentifier()))
-        return false;
-    }
-
-    DC1 = DC1->getParent()->getNonTransparentContext();
-    DC2 = DC2->getParent()->getNonTransparentContext();
-  }
-
-  return true;
-}
-
 /// Determine structural equivalence of two records.
 static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
                                      RecordDecl *D1, RecordDecl *D2) {
@@ -1422,12 +1386,6 @@
     }
   }
 
-  // If the records occur in different context (namespace), these should be
-  // different. This is specially important if the definition of one or both
-  // records is missing.
-  if (!IsRecordContextStructurallyEquivalent(D1, D2))
-    return false;
-
   // If both declarations are class template specializations, we know
   // the ODR applies, so check the template and template arguments.
   const auto *Spec1 = dyn_cast<ClassTemplateSpecializationDecl>(D1);
diff --git a/unittests/AST/StructuralEquivalenceTest.cpp b/unittests/AST/StructuralEquivalenceTest.cpp
index 2f5b5c1..9ae0da8 100644
--- a/unittests/AST/StructuralEquivalenceTest.cpp
+++ b/unittests/AST/StructuralEquivalenceTest.cpp
@@ -929,136 +929,6 @@
   EXPECT_TRUE(testStructuralMatch(First, Second));
 }
 
-struct StructuralEquivalenceRecordContextTest : StructuralEquivalenceTest {};
-
-TEST_F(StructuralEquivalenceRecordContextTest, NamespaceNoVsNamed) {
-  auto Decls = makeDecls<CXXRecordDecl>("class X;", "namespace N { class X; }",
-                                        Lang_CXX03, cxxRecordDecl());
-  EXPECT_FALSE(testStructuralMatch(Decls));
-}
-
-TEST_F(StructuralEquivalenceRecordContextTest, NamespaceNamedVsNamed) {
-  auto Decls = makeDecls<CXXRecordDecl>("namespace A { class X; }",
-                                        "namespace B { class X; }", Lang_CXX03,
-                                        cxxRecordDecl());
-  EXPECT_FALSE(testStructuralMatch(Decls));
-}
-
-TEST_F(StructuralEquivalenceRecordContextTest, NamespaceAnonVsNamed) {
-  auto Decls = makeDecls<CXXRecordDecl>("namespace { class X; }",
-                                        "namespace N { class X; }", Lang_CXX03,
-                                        cxxRecordDecl());
-  EXPECT_FALSE(testStructuralMatch(Decls));
-}
-
-TEST_F(StructuralEquivalenceRecordContextTest, NamespaceNoVsAnon) {
-  auto Decls = makeDecls<CXXRecordDecl>("class X;", "namespace { class X; }",
-                                        Lang_CXX03, cxxRecordDecl());
-  EXPECT_FALSE(testStructuralMatch(Decls));
-}
-
-TEST_F(StructuralEquivalenceRecordContextTest, NamespaceAnonVsAnon) {
-  auto Decls = makeDecls<CXXRecordDecl>("namespace { class X; }",
-                                        "namespace { class X; }", Lang_CXX03,
-                                        cxxRecordDecl());
-  EXPECT_TRUE(testStructuralMatch(Decls));
-}
-
-TEST_F(StructuralEquivalenceRecordContextTest, NamespaceAnonVsAnonAnon) {
-  auto Decls = makeDecls<CXXRecordDecl>("namespace { class X; }",
-                                        "namespace { namespace { class X; } }",
-                                        Lang_CXX03, cxxRecordDecl());
-  EXPECT_FALSE(testStructuralMatch(Decls));
-}
-
-TEST_F(StructuralEquivalenceRecordContextTest,
-       NamespaceNamedNamedVsNamedNamed) {
-  auto Decls = makeDecls<CXXRecordDecl>(
-      "namespace A { namespace N { class X; } }",
-      "namespace B { namespace N { class X; } }", Lang_CXX03, cxxRecordDecl());
-  EXPECT_FALSE(testStructuralMatch(Decls));
-}
-
-TEST_F(StructuralEquivalenceRecordContextTest, NamespaceNamedVsInline) {
-  auto Decls = makeDecls<CXXRecordDecl>(
-      "namespace A { namespace A { class X; } }",
-      "namespace A { inline namespace A { class X; } }", Lang_CXX17,
-      cxxRecordDecl());
-  EXPECT_FALSE(testStructuralMatch(Decls));
-}
-
-TEST_F(StructuralEquivalenceRecordContextTest, NamespaceInlineVsInline) {
-  auto Decls = makeDecls<CXXRecordDecl>(
-      "namespace A { inline namespace A { class X; } }",
-      "namespace A { inline namespace B { class X; } }", Lang_CXX17,
-      cxxRecordDecl());
-  EXPECT_TRUE(testStructuralMatch(Decls));
-}
-
-TEST_F(StructuralEquivalenceRecordContextTest, NamespaceInlineTopLevel) {
-  auto Decls = makeDecls<CXXRecordDecl>("inline namespace A { class X; } }",
-                                        "inline namespace B { class X; } }",
-                                        Lang_CXX17, cxxRecordDecl());
-  EXPECT_TRUE(testStructuralMatch(Decls));
-}
-
-TEST_F(StructuralEquivalenceRecordContextTest, TransparentContext) {
-  auto Decls = makeDecls<CXXRecordDecl>("extern \"C\" { class X; }", "class X;",
-                                        Lang_CXX03, cxxRecordDecl());
-  EXPECT_TRUE(testStructuralMatch(Decls));
-}
-
-TEST_F(StructuralEquivalenceRecordContextTest, TransparentContextNE) {
-  auto Decls = makeDecls<CXXRecordDecl>("extern \"C\" { class X; }",
-                                        "namespace { class X; }", Lang_CXX03,
-                                        cxxRecordDecl());
-  EXPECT_FALSE(testStructuralMatch(Decls));
-}
-
-TEST_F(StructuralEquivalenceRecordContextTest, TransparentContextInNamespace) {
-  auto Decls = makeDecls<CXXRecordDecl>(
-      "extern \"C\" { namespace N { class X; } }",
-      "namespace N { extern \"C\" { class X; } }", Lang_CXX03, cxxRecordDecl());
-  EXPECT_TRUE(testStructuralMatch(Decls));
-}
-
-TEST_F(StructuralEquivalenceTest, NamespaceOfRecordMember) {
-  auto Decls = makeDecls<CXXRecordDecl>(
-      R"(
-      class X;
-      class Y { X* x; };
-      )",
-      R"(
-      namespace N { class X; }
-      class Y { N::X* x; };
-      )",
-      Lang_CXX03, cxxRecordDecl(hasName("Y")));
-  EXPECT_FALSE(testStructuralMatch(Decls));
-}
-
-TEST_F(StructuralEquivalenceTest, StructDefinitionInPrototype) {
-  auto Decls = makeDecls<FunctionDecl>(
-      "struct Param { int a; }; void f(struct Param *p);",
-      "void f(struct Param { int a; } *p);", Lang_C89,
-      functionDecl(hasName("f")));
-  EXPECT_TRUE(testStructuralMatch(Decls));
-}
-
-TEST_F(StructuralEquivalenceTest, StructDefinitionInPrototypeDifferentName) {
-  auto Decls = makeDecls<FunctionDecl>(
-      "struct Param1 { int a; }; void f(struct Param1 *p);",
-      "void f(struct Param2 { int a; } *p);", Lang_C89,
-      functionDecl(hasName("f")));
-  EXPECT_FALSE(testStructuralMatch(Decls));
-}
-
-TEST_F(StructuralEquivalenceRecordContextTest, RecordInsideFunction) {
-  auto Decls = makeDecls<RecordDecl>("struct Param { int a; };",
-                                     "void f() { struct Param { int a; }; }",
-                                     Lang_C89, recordDecl(hasName("Param")));
-  EXPECT_TRUE(testStructuralMatch(Decls));
-}
-
 struct StructuralEquivalenceEnumTest : StructuralEquivalenceTest {};
 
 TEST_F(StructuralEquivalenceEnumTest, FwdDeclEnumShouldBeEqualWithFwdDeclEnum) {