Add a clarifying comment that a datastructure is filled in by emitFiles.

Author: bd1976bris

llvm/lib/LTO/LTO.cpp

@@ -2270,11 +2270,13 @@ class OutOfProcessThinBackend : public CGThinBackend {
                                        itostr(Task) + "." + UID + ".native.o");
 
     Job &J = Jobs[Task - ThinLTOTaskOffset];
-    J = {Task,
-         ModulePath,
-         Saver.save(ObjFilePath.str()),
-         Saver.save(ObjFilePath.str() + ".thinlto.bc"),
-         {}};
+    J = {
+        Task,
+        ModulePath,
+        Saver.save(ObjFilePath.str()),
+        Saver.save(ObjFilePath.str() + ".thinlto.bc"),
+        {} // Filled in by emitFiles below.
+    };
 
     assert(ModuleToDefinedGVSummaries.count(ModulePath));
     BackendThreadPool.async(