Fix 41 of the 61 tests which fail with modules enabled: we were computing and

caching the linkage for a declaration before we set up its redeclaration chain,
when determining whether a declaration could be a redeclaration of something
from an unimported submodule. We actually want to look at the declaration as if
it were not a redeclaration here, so compute the linkage but don't cache it.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@178733 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 16 insertions, 2 deletions

diff --git a/lib/AST/Decl.cpp b/lib/AST/Decl.cpp
index 9505d299ab..bf807aeb1d 100644
--- a/lib/AST/Decl.cpp
+++ b/lib/AST/Decl.cpp
@@ -866,6 +866,10 @@ bool NamedDecl::isLinkageValid() const {
     Linkage(CachedLinkage);
 }
 
+bool NamedDecl::hasExternalLinkageUncached() const {
+  return getLVForDecl(this, LVForExplicitValue).getLinkage() == ExternalLinkage;
+}
+
 Linkage NamedDecl::getLinkage() const {
   if (HasCachedLinkage)
     return Linkage(CachedLinkage);
diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index 1288568401..42d7d2bdf5 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -1605,8 +1605,18 @@ static void filterNonConflictingPreviousDecls(ASTContext &context,
   if (previous.empty())
     return;
 
-  // If this declaration has external
-  bool hasExternalLinkage = decl->hasExternalLinkage();
+  // If this declaration would have external linkage if it were the first
+  // declaration of this name, then it may in fact be a redeclaration of
+  // some hidden declaration, so include those too. We don't need to worry
+  // about some previous visible declaration giving this declaration external
+  // linkage, because in that case, we'll mark this declaration as a redecl
+  // of the visible decl, and that decl will already be a redecl of the
+  // hidden declaration if that's appropriate.
+  //
+  // Don't cache this linkage computation, because it's not yet correct: we
+  // may later give this declaration a previous declaration which changes
+  // its linkage.
+  bool hasExternalLinkage = decl->hasExternalLinkageUncached();
 
   LookupResult::Filter filter = previous.makeFilter();
   while (filter.hasNext()) {