diff --git a/lib/Frontend/CompilerInvocation.cpp b/lib/Frontend/CompilerInvocation.cpp
index d1de31b..b8b5011 100644
--- a/lib/Frontend/CompilerInvocation.cpp
+++ b/lib/Frontend/CompilerInvocation.cpp
@@ -1477,6 +1477,9 @@
   if (Args.hasArg(OPT_fno_operator_names))
     Opts.CXXOperatorNames = 0;
 
+  if (Args.hasArg(OPT_fgnu89_inline))
+    Opts.GNUInline = 1;
+
   if (Args.hasArg(OPT_fobjc_gc_only))
     Opts.setGCMode(LangOptions::GCOnly);
   else if (Args.hasArg(OPT_fobjc_gc))