From 0128dc8835c73dac96aa100bd5664b426c95c0a6 Mon Sep 17 00:00:00 2001
From: Richard Smith <richard-llvm@metafoo.co.uk>
Date: Tue, 4 Aug 2015 02:05:09 +0000
Subject: [PATCH] [modules] Make IndirectFieldDecl mergeable to avoid lookup
ambiguity when the same anonymous union is defined across multiple modules.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@243940 91177308-0d34-0410-b5e6-96231b3b80d8
---
include/clang/AST/Decl.h | 6 +++++-
lib/Serialization/ASTReaderDecl.cpp | 9 +++++++++
test/Modules/Inputs/submodules-merge-defs/defs.h | 8 ++++++++
test/Modules/submodules-merge-defs.cpp | 1 +
4 files changed, 23 insertions(+), 1 deletion(-)
diff --git a/include/clang/AST/Decl.h b/include/clang/AST/Decl.h
index 76c05852f72..76fda1c0915 100644
--- a/include/clang/AST/Decl.h
+++ b/include/clang/AST/Decl.h
@@ -2499,7 +2499,8 @@ public:
/// IndirectFieldDecl - An instance of this class is created to represent a
/// field injected from an anonymous union/struct into the parent scope.
/// IndirectFieldDecl are always implicit.
-class IndirectFieldDecl : public ValueDecl {
+class IndirectFieldDecl : public ValueDecl,
+ public Mergeable<IndirectFieldDecl> {
void anchor() override;
NamedDecl **Chaining;
unsigned ChainingSize;
@@ -2537,6 +2538,9 @@ public:
return dyn_cast<VarDecl>(*chain_begin());
}
+ IndirectFieldDecl *getCanonicalDecl() override { return getFirstDecl(); }
+ const IndirectFieldDecl *getCanonicalDecl() const { return getFirstDecl(); }
+
// Implement isa/cast/dyncast/etc.
static bool classof(const Decl *D) { return classofKind(D->getKind()); }
static bool classofKind(Kind K) { return K == IndirectField; }
diff --git a/lib/Serialization/ASTReaderDecl.cpp b/lib/Serialization/ASTReaderDecl.cpp
index 45a3e45bbcf..0242e7eed07 100644
--- a/lib/Serialization/ASTReaderDecl.cpp
+++ b/lib/Serialization/ASTReaderDecl.cpp
@@ -1178,6 +1178,8 @@ void ASTDeclReader::VisitIndirectFieldDecl(IndirectFieldDecl *FD) {
for (unsigned I = 0; I != FD->ChainingSize; ++I)
FD->Chaining[I] = ReadDeclAs<NamedDecl>(Record, Idx);
+
+ mergeMergeable(FD);
}
ASTDeclReader::RedeclarableResult ASTDeclReader::VisitVarDeclImpl(VarDecl *VD) {
@@ -2638,6 +2640,13 @@ static bool isSameEntity(NamedDecl *X, NamedDecl *Y) {
return X->getASTContext().hasSameType(FDX->getType(), FDY->getType());
}
+ // Indirect fields with the same target field match.
+ if (auto *IFDX = dyn_cast<IndirectFieldDecl>(X)) {
+ auto *IFDY = cast<IndirectFieldDecl>(Y);
+ return IFDX->getAnonField()->getCanonicalDecl() ==
+ IFDY->getAnonField()->getCanonicalDecl();
+ }
+
// Enumerators with the same name match.
if (isa<EnumConstantDecl>(X))
// FIXME: Also check the value is odr-equivalent.
diff --git a/test/Modules/Inputs/submodules-merge-defs/defs.h b/test/Modules/Inputs/submodules-merge-defs/defs.h
index e4c86d80ba6..670c400ae3b 100644
--- a/test/Modules/Inputs/submodules-merge-defs/defs.h
+++ b/test/Modules/Inputs/submodules-merge-defs/defs.h
@@ -103,3 +103,11 @@ namespace RedeclDifferentDeclKind {
typedef X X;
using RedeclDifferentDeclKind::X;
}
+
+namespace Anon {
+ struct X {
+ union {
+ int n;
+ };
+ };
+}
diff --git a/test/Modules/submodules-merge-defs.cpp b/test/Modules/submodules-merge-defs.cpp
index 016b8a8f47a..62cbbd51098 100644
--- a/test/Modules/submodules-merge-defs.cpp
+++ b/test/Modules/submodules-merge-defs.cpp
@@ -104,6 +104,7 @@ template<typename T, int N, template<typename> class K> struct J;
J<> post_j2;
FriendDefArg::Y<int> friend_def_arg;
FriendDefArg::D<> friend_def_arg_d;
+int post_anon_x_n = Anon::X().n;
MergeFunctionTemplateSpecializations::X<int>::Q<char> xiqc;
--
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