[llvm-branch-commits] [clang] f1ca50a - D88665 id 295585 [ASTImporter][AST] Fix structural equivalency crash on dependent FieldDecl

[Gabor Marton via llvm-branch-commits]

Author: Gabor Marton
Date: 2020-10-14T11:15:06+02:00
New Revision: f1ca50a5094653463e350daa6c508885f61f11b4

URL: https://github.com/llvm/llvm-project/commit/f1ca50a5094653463e350daa6c508885f61f11b4
DIFF: https://github.com/llvm/llvm-project/commit/f1ca50a5094653463e350daa6c508885f61f11b4.diff

LOG: D88665 id 295585 [ASTImporter][AST] Fix structural equivalency crash on dependent FieldDecl

Added: 
    

Modified: 
    clang/lib/AST/ASTStructuralEquivalence.cpp
    clang/unittests/AST/StructuralEquivalenceTest.cpp

Removed: 
    


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diff  --git a/clang/lib/AST/ASTStructuralEquivalence.cpp b/clang/lib/AST/ASTStructuralEquivalence.cpp
index 8b5b2444f1e2..3dcd4159dc0b 100644
--- a/clang/lib/AST/ASTStructuralEquivalence.cpp
+++ b/clang/lib/AST/ASTStructuralEquivalence.cpp
@@ -1071,6 +1071,10 @@ static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
   }
 
   if (Field1->isBitField()) {
+    bool isVD1 = Field1->getBitWidth()->isValueDependent();
+    bool isVD2 = Field2->getBitWidth()->isValueDependent();
+    if (isVD1 || isVD2)
+      return isVD1 && isVD2;
     // Make sure that the bit-fields are the same length.
     unsigned Bits1 = Field1->getBitWidthValue(Context.FromCtx);
     unsigned Bits2 = Field2->getBitWidthValue(Context.ToCtx);

diff  --git a/clang/unittests/AST/StructuralEquivalenceTest.cpp b/clang/unittests/AST/StructuralEquivalenceTest.cpp
index 2b5ce0fed51d..b5aff49eaaee 100644
--- a/clang/unittests/AST/StructuralEquivalenceTest.cpp
+++ b/clang/unittests/AST/StructuralEquivalenceTest.cpp
@@ -906,6 +906,12 @@ TEST_F(StructuralEquivalenceTemplateTest, DifferentTemplateArgKind) {
   EXPECT_FALSE(testStructuralMatch(t));
 }
 
+TEST_F(StructuralEquivalenceTemplateTest, DependentFieldDecl) {
+  const char *Code = "template <class T> class foo { int a : sizeof(T); };";
+  auto t = makeNamedDecls(Code, Code, Lang_CXX03);
+  EXPECT_TRUE(testStructuralMatch(t));
+}
+
 TEST_F(StructuralEquivalenceTemplateTest, ExplicitBoolSame) {
   auto Decls = makeNamedDecls(
       "template <bool b> struct foo {explicit(b) foo(int);};",