From: Gabor Marton <gabor.marton@ericsson.com>
Date: Wed, 17 Jul 2019 14:40:09 +0000 (+0000)
Subject: [ASTImporter] Fix structural eq of lambdas
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=6d72dd4563e527d09f61b4b3dfafa551bb44bd20;p=clang

[ASTImporter] Fix structural eq of lambdas

Summary:
The structural equivalence check reported false eq between lambda classes
with different parameters in their call signature.
The solution is to check the methods for equality too in case of lambda
classes.

Reviewers: a_sidorin, a.sidorin

Subscribers: rnkovacs, dkrupp, Szelethus, gamesh411, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D64075

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@366332 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/AST/ASTStructuralEquivalence.cpp b/lib/AST/ASTStructuralEquivalence.cpp
index bb2e353eee..912db3c130 100644
--- a/lib/AST/ASTStructuralEquivalence.cpp
+++ b/lib/AST/ASTStructuralEquivalence.cpp
@@ -1085,6 +1085,19 @@ static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
   return true;
 }
 
+/// Determine structural equivalence of two lambda classes.
+static bool
+IsStructurallyEquivalentLambdas(StructuralEquivalenceContext &Context,
+                                CXXRecordDecl *D1, CXXRecordDecl *D2) {
+  assert(D1->isLambda() && D2->isLambda() &&
+         "Must be called on lambda classes");
+  if (!IsStructurallyEquivalent(Context, D1->getLambdaCallOperator(),
+                                D2->getLambdaCallOperator()))
+    return false;
+
+  return true;
+}
+
 /// Determine structural equivalence of two records.
 static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
                                      RecordDecl *D1, RecordDecl *D2) {
@@ -1166,6 +1179,13 @@ static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
         D1CXX->getASTContext().getExternalSource()->CompleteType(D1CXX);
       }
 
+      if (D1CXX->isLambda() != D2CXX->isLambda())
+        return false;
+      if (D1CXX->isLambda()) {
+        if (!IsStructurallyEquivalentLambdas(Context, D1CXX, D2CXX))
+          return false;
+      }
+
       if (D1CXX->getNumBases() != D2CXX->getNumBases()) {
         if (Context.Complain) {
           Context.Diag2(D2->getLocation(),
diff --git a/unittests/AST/ASTImporterTest.cpp b/unittests/AST/ASTImporterTest.cpp
index 8b2f7c5b24..6ea350cc72 100644
--- a/unittests/AST/ASTImporterTest.cpp
+++ b/unittests/AST/ASTImporterTest.cpp
@@ -5122,6 +5122,22 @@ TEST_P(ASTImporterOptionSpecificTestBase, LambdaInFunctionParam) {
   EXPECT_EQ(ToLSize, FromLSize);
 }
 
+TEST_P(ASTImporterOptionSpecificTestBase, LambdaInGlobalScope) {
+  Decl *FromTU = getTuDecl(
+      R"(
+      auto l1 = [](unsigned lp) { return 1; };
+      auto l2 = [](int lp) { return 2; };
+      int f(int p) {
+        return l1(p) + l2(p);
+      }
+      )",
+      Lang_CXX11, "input0.cc");
+  FunctionDecl *FromF = FirstDeclMatcher<FunctionDecl>().match(
+      FromTU, functionDecl(hasName("f")));
+  FunctionDecl *ToF = Import(FromF, Lang_CXX11);
+  EXPECT_TRUE(ToF);
+}
+
 struct LLDBLookupTest : ASTImporterOptionSpecificTestBase {
   LLDBLookupTest() {
     Creator = [](ASTContext &ToContext, FileManager &ToFileManager,
diff --git a/unittests/AST/StructuralEquivalenceTest.cpp b/unittests/AST/StructuralEquivalenceTest.cpp
index 63757987e1..cdb55d90b9 100644
--- a/unittests/AST/StructuralEquivalenceTest.cpp
+++ b/unittests/AST/StructuralEquivalenceTest.cpp
@@ -797,6 +797,58 @@ TEST_F(StructuralEquivalenceRecordTest, RecordsWithDifferentBody) {
   EXPECT_FALSE(testStructuralMatch(t));
 }
 
+struct StructuralEquivalenceLambdaTest : StructuralEquivalenceTest {};
+
+TEST_F(StructuralEquivalenceLambdaTest, LambdaClassesWithDifferentMethods) {
+  // Get the LambdaExprs, unfortunately we can't match directly the underlying
+  // implicit CXXRecordDecl of the Lambda classes.
+  auto t = makeDecls<LambdaExpr>(
+      "void f() { auto L0 = [](int){}; }",
+      "void f() { auto L1 = [](){}; }",
+      Lang_CXX11,
+      lambdaExpr(),
+      lambdaExpr());
+  CXXRecordDecl *L0 = get<0>(t)->getLambdaClass();
+  CXXRecordDecl *L1 = get<1>(t)->getLambdaClass();
+  EXPECT_FALSE(testStructuralMatch(L0, L1));
+}
+
+TEST_F(StructuralEquivalenceLambdaTest, LambdaClassesWithEqMethods) {
+  auto t = makeDecls<LambdaExpr>(
+      "void f() { auto L0 = [](int){}; }",
+      "void f() { auto L1 = [](int){}; }",
+      Lang_CXX11,
+      lambdaExpr(),
+      lambdaExpr());
+  CXXRecordDecl *L0 = get<0>(t)->getLambdaClass();
+  CXXRecordDecl *L1 = get<1>(t)->getLambdaClass();
+  EXPECT_TRUE(testStructuralMatch(L0, L1));
+}
+
+TEST_F(StructuralEquivalenceLambdaTest, LambdaClassesWithDifferentFields) {
+  auto t = makeDecls<LambdaExpr>(
+      "void f() { char* X; auto L0 = [X](){}; }",
+      "void f() { float X; auto L1 = [X](){}; }",
+      Lang_CXX11,
+      lambdaExpr(),
+      lambdaExpr());
+  CXXRecordDecl *L0 = get<0>(t)->getLambdaClass();
+  CXXRecordDecl *L1 = get<1>(t)->getLambdaClass();
+  EXPECT_FALSE(testStructuralMatch(L0, L1));
+}
+
+TEST_F(StructuralEquivalenceLambdaTest, LambdaClassesWithEqFields) {
+  auto t = makeDecls<LambdaExpr>(
+      "void f() { float X; auto L0 = [X](){}; }",
+      "void f() { float X; auto L1 = [X](){}; }",
+      Lang_CXX11,
+      lambdaExpr(),
+      lambdaExpr());
+  CXXRecordDecl *L0 = get<0>(t)->getLambdaClass();
+  CXXRecordDecl *L1 = get<1>(t)->getLambdaClass();
+  EXPECT_TRUE(testStructuralMatch(L0, L1));
+}
+
 TEST_F(StructuralEquivalenceTest, CompareSameDeclWithMultiple) {
   auto t = makeNamedDecls(
       "struct A{ }; struct B{ }; void foo(A a, A b);",