C++ modules: fix a bug where loading a declaration with some name would prevent

name lookup from lazily deserializing the other declarations with the same
name, by tracking a bit to indicate whether a name in a DeclContext might have
additional external results. This also allows lazier reconciling of the lookup
table if a module import adds decls to a pre-existing DC.

However, this exposes a pre-existing bug, which causes a regression in
test/Modules/decldef.mm: if we have a reference to a declaration, and a
later-imported module adds a redeclaration, nothing causes us to load that
redeclaration when we use or emit the reference (which can manifest as a
reference to an undefined inline function, a use of an incomplete type, and so
on). decldef.mm has been extended with an additional testcase which fails with
or without this change.

llvm-svn: 190293

1 files changed, 5 insertions, 0 deletions

diff --git a/clang/test/Modules/Inputs/namespaces-top.h b/clang/test/Modules/Inputs/namespaces-top.h
index 0c607f52851..7aa8490eb7e 100644
--- a/clang/test/Modules/Inputs/namespaces-top.h
+++ b/clang/test/Modules/Inputs/namespaces-top.h
@@ -12,3 +12,8 @@ namespace N3 {
 
 namespace N12 { }
 
+namespace N13 {
+  void f();
+  int f(int);
+  void (*p)() = &f;
+}