[Modules TS] Module ownership semantics for redeclarations.
When declaring an entity in the "purview" of a module, it's never a
redeclaration of an entity in the purview of a default module or in no module
("in the global module"). Don't consider those other declarations as possible
redeclaration targets if they're not visible, and reject any cases where we
pick a prior visible declaration that violates this rule.
This reinstates r315251 and r315256, reverted in r315309 and r315308
respectively, tweaked to avoid triggering a linkage calculation when declaring
implicit special members (this exposed our pre-existing issue with typedef
names for linkage changing the linkage of types whose linkage has already been
computed and cached in more cases). A testcase for that regression has been
added in r315366.
llvm-svn: 315379
diff --git a/clang/lib/AST/Decl.cpp b/clang/lib/AST/Decl.cpp
index 6e5f638..4a9b9be 100644
--- a/clang/lib/AST/Decl.cpp
+++ b/clang/lib/AST/Decl.cpp
@@ -515,6 +515,7 @@
}
static bool isExportedFromModuleIntefaceUnit(const NamedDecl *D) {
+ // FIXME: Handle isModulePrivate.
switch (D->getModuleOwnershipKind()) {
case Decl::ModuleOwnershipKind::Unowned:
case Decl::ModuleOwnershipKind::ModulePrivate:
@@ -546,7 +547,8 @@
// declaration has module linkage.
if (auto *M = D->getOwningModule())
if (M->Kind == Module::ModuleInterfaceUnit)
- if (!isExportedFromModuleIntefaceUnit(D))
+ if (!isExportedFromModuleIntefaceUnit(
+ cast<NamedDecl>(D->getCanonicalDecl())))
return LinkageInfo(ModuleLinkage, DefaultVisibility, false);
return LinkageInfo::external();
@@ -1393,7 +1395,7 @@
: NamedDecl::VisibilityForValue));
}
-Module *NamedDecl::getOwningModuleForLinkage() const {
+Module *Decl::getOwningModuleForLinkage(bool IgnoreLinkage) const {
Module *M = getOwningModule();
if (!M)
return nullptr;
@@ -1411,7 +1413,17 @@
// for linkage purposes. But internal linkage declarations in the global
// module fragment of a particular module are owned by that module for
// linkage purposes.
- return hasExternalFormalLinkage() ? nullptr : M->Parent;
+ if (IgnoreLinkage)
+ return nullptr;
+ bool InternalLinkage;
+ if (auto *ND = dyn_cast<NamedDecl>(this))
+ InternalLinkage = !ND->hasExternalFormalLinkage();
+ else {
+ auto *NSD = dyn_cast<NamespaceDecl>(this);
+ InternalLinkage = (NSD && NSD->isAnonymousNamespace()) ||
+ isInAnonymousNamespace();
+ }
+ return InternalLinkage ? M->Parent : nullptr;
}
llvm_unreachable("unknown module kind");