maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity

[ASTImporter] Fix for import of friend class template with definition. 

Summary:
If there is a friend class template "prototype" (forward declaration)
and later a definition for it in the existing code, this existing
definition may be not found by ASTImporter because it is not linked
to the prototype (under the friend AST node). The problem is fixed by
looping over all found matching decls instead of break after the first
found one.

Reviewers: martong, a.sidorin, shafik, a_sidorin

Reviewed By: a_sidorin

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

Tags: #clang

Differential Revision: https://reviews.llvm.org/D65269

llvm-svn: 368551
This commit is contained in:
Balazs Keri 2019-08-12 10:07:38 +00:00
parent 3cafdfddcb
commit 2e16060a8b
2 changed files with 50 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
clang/lib/AST/ASTImporter.cpp
View File

@ -5082,11 +5082,13 @@ ExpectedDecl ASTNodeImporter::VisitClassTemplateDecl(ClassTemplateDecl *D) {
if (IsStructuralMatch(D, FoundTemplate)) {
ClassTemplateDecl *TemplateWithDef =
getTemplateDefinition(FoundTemplate);
if (D->isThisDeclarationADefinition() && TemplateWithDef) {
if (D->isThisDeclarationADefinition() && TemplateWithDef)
return Importer.MapImported(D, TemplateWithDef);
}
FoundByLookup = FoundTemplate;
break;
if (!FoundByLookup)
FoundByLookup = FoundTemplate;
// Search in all matches because there may be multiple decl chains,
// see ASTTests test ImportExistingFriendClassTemplateDef.
continue;
}
}

44
clang/unittests/AST/ASTImporterTest.cpp
View File

@ -5191,6 +5191,50 @@ TEST_P(ASTImporterOptionSpecificTestBase, LambdaInGlobalScope) {
EXPECT_TRUE(ToF);
}
TEST_P(ASTImporterOptionSpecificTestBase,
ImportExistingFriendClassTemplateDef) {
auto Code =
R"(
template <class T1, class T2>
struct Base {
template <class U1, class U2>
friend struct Class;
};
template <class T1, class T2>
struct Class { };
)";
TranslationUnitDecl *ToTU = getToTuDecl(Code, Lang_CXX);
TranslationUnitDecl *FromTU = getTuDecl(Code, Lang_CXX, "input.cc");
auto *ToClassProto = FirstDeclMatcher<ClassTemplateDecl>().match(
ToTU, classTemplateDecl(hasName("Class")));
auto *ToClassDef = LastDeclMatcher<ClassTemplateDecl>().match(
ToTU, classTemplateDecl(hasName("Class")));
ASSERT_FALSE(ToClassProto->isThisDeclarationADefinition());
ASSERT_TRUE(ToClassDef->isThisDeclarationADefinition());
// Previous friend decl is not linked to it!
ASSERT_FALSE(ToClassDef->getPreviousDecl());
ASSERT_EQ(ToClassDef->getMostRecentDecl(), ToClassDef);
ASSERT_EQ(ToClassProto->getMostRecentDecl(), ToClassProto);
auto *FromClassProto = FirstDeclMatcher<ClassTemplateDecl>().match(
FromTU, classTemplateDecl(hasName("Class")));
auto *FromClassDef = LastDeclMatcher<ClassTemplateDecl>().match(
FromTU, classTemplateDecl(hasName("Class")));
ASSERT_FALSE(FromClassProto->isThisDeclarationADefinition());
ASSERT_TRUE(FromClassDef->isThisDeclarationADefinition());
ASSERT_FALSE(FromClassDef->getPreviousDecl());
ASSERT_EQ(FromClassDef->getMostRecentDecl(), FromClassDef);
ASSERT_EQ(FromClassProto->getMostRecentDecl(), FromClassProto);
auto *ImportedDef = Import(FromClassDef, Lang_CXX);
// At import we should find the definition for 'Class' even if the
// prototype (inside 'friend') for it comes first in the AST and is not
// linked to the definition.
EXPECT_EQ(ImportedDef, ToClassDef);
}
struct LLDBLookupTest : ASTImporterOptionSpecificTestBase {
LLDBLookupTest() {
Creator = [](ASTContext &ToContext, FileManager &ToFileManager,