Make clang emit linkage names in debug info for subprograms when coverage info
is enabled. Also add a new -test-coverage cc1 flag which makes testing coverage
possible and add our first clang-side coverage test.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@177470 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/BackendUtil.cpp b/lib/CodeGen/BackendUtil.cpp
index 9c9c561..23d8b97 100644
--- a/lib/CodeGen/BackendUtil.cpp
+++ b/lib/CodeGen/BackendUtil.cpp
@@ -302,7 +302,8 @@
   // Set up the per-module pass manager.
   PassManager *MPM = getPerModulePasses(TM);
 
-  if (CodeGenOpts.EmitGcovArcs || CodeGenOpts.EmitGcovNotes) {
+  if (!CodeGenOpts.DisableGCov &&
+      (CodeGenOpts.EmitGcovArcs || CodeGenOpts.EmitGcovNotes)) {
     // Not using 'GCOVOptions::getDefault' allows us to avoid exiting if
     // LLVM's -default-gcov-version flag is set to something invalid.
     GCOVOptions Options;