clang-cl: pass -debug flag to the linker when compiling with debug info

llvm-svn: 207233
diff --git a/clang/lib/Driver/Tools.cpp b/clang/lib/Driver/Tools.cpp
index 0a45fa1..924e040 100644
--- a/clang/lib/Driver/Tools.cpp
+++ b/clang/lib/Driver/Tools.cpp
@@ -7435,6 +7435,10 @@
 
   CmdArgs.push_back("-nologo");
 
+  if (Args.hasArg(options::OPT_g_Group)) {
+    CmdArgs.push_back("-debug");
+  }
+
   bool DLL = Args.hasArg(options::OPT__SLASH_LD, options::OPT__SLASH_LDd);
 
   if (DLL) {