Ensure that we clean up after a failed module build and cope with the
results in libclang.

llvm-svn: 149200
diff --git a/clang/lib/Frontend/ASTUnit.cpp b/clang/lib/Frontend/ASTUnit.cpp
index c23c644..abeb317 100644
--- a/clang/lib/Frontend/ASTUnit.cpp
+++ b/clang/lib/Frontend/ASTUnit.cpp
@@ -576,6 +576,9 @@
   DiagnosticConsumer *clone(DiagnosticsEngine &Diags) const {
     // Just drop any diagnostics that come from cloned consumers; they'll
     // have different source managers anyway.
+    // FIXME: We'd like to be able to capture these somehow, even if it's just
+    // file/line/column, because they could occur when parsing module maps or
+    // building modules on-demand.
     return new IgnoringDiagConsumer();
   }
 };
diff --git a/clang/lib/Frontend/CompilerInstance.cpp b/clang/lib/Frontend/CompilerInstance.cpp
index cc8d3b4..4f6ba16 100644
--- a/clang/lib/Frontend/CompilerInstance.cpp
+++ b/clang/lib/Frontend/CompilerInstance.cpp
@@ -926,7 +926,7 @@
   const unsigned MaxSeconds = 3600;
   do {
     // Sleep for the designated interval, to allow the owning process time to
-    // finish up and
+    // finish up and remove the lock file.
     // FIXME: Should we hook in to system APIs to get a notification when the
     // lock file is deleted?
 #if LLVM_ON_WIN32