Implement support for wildcard exports in modules, allowing a module

to re-export anything that it imports. This opt-in feature makes a
module behave more like a header, because it can be used to re-export
the transitive closure of a (sub)module's dependencies.

llvm-svn: 145811

clang/lib/Basic/Module.cpp

@@ -25,6 +25,18 @@ Module::~Module() {
   
 }
 
+bool Module::isSubModuleOf(Module *Other) const {
+  const Module *This = this;
+  do {
+    if (This == Other)
+      return true;
+    
+    This = This->Parent;
+  } while (This);
+  
+  return false;
+}
+
 std::string Module::getFullModuleName() const {
   llvm::SmallVector<StringRef, 2> Names;