diff --git a/lib/Frontend/CompilerInvocation.cpp b/lib/Frontend/CompilerInvocation.cpp
index 05d2e69..76ceb9b 100644
--- a/lib/Frontend/CompilerInvocation.cpp
+++ b/lib/Frontend/CompilerInvocation.cpp
@@ -131,6 +131,10 @@
     Res.push_back("-disable-llvm-optzns");
   if (Opts.DisableRedZone)
     Res.push_back("-disable-red-zone");
+  if (!Opts.DebugCompilationDir.empty()) {
+    Res.push_back("-fdebug-compilation-dir");
+    Res.push_back(Opts.DebugCompilationDir);
+  }
   if (!Opts.DwarfDebugFlags.empty()) {
     Res.push_back("-dwarf-debug-flags");
     Res.push_back(Opts.DwarfDebugFlags);
@@ -1071,6 +1075,7 @@
   Opts.EmitGcovArcs = Args.hasArg(OPT_femit_coverage_data);
   Opts.EmitGcovNotes = Args.hasArg(OPT_femit_coverage_notes);
   Opts.CoverageFile = Args.getLastArgValue(OPT_coverage_file);
+  Opts.DebugCompilationDir = Args.getLastArgValue(OPT_fdebug_compilation_dir);
 
   if (Arg *A = Args.getLastArg(OPT_fobjc_dispatch_method_EQ)) {
     StringRef Name = A->getValue(Args);