Chris says it's better to assert that TheModule is valid than silently return 0.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@9212 91177308-0d34-0410-b5e6-96231b3b80d8

lib/VMCore/ModuleProvider.cpp

@@ -20,8 +20,7 @@ ModuleProvider::~ModuleProvider() {
 /// materializeFunction - make sure the given function is fully read.
 ///
 Module* ModuleProvider::materializeModule() {
-  // FIXME: throw an exception instead?
-  if (!TheModule) return 0;
+  assert(TheModule && "Attempting to materialize an invalid module!");
 
   for (Module::iterator i = TheModule->begin(), e = TheModule->end();
        i != e; ++i)