diff --git a/lib/CodeGen/CGCall.cpp b/lib/CodeGen/CGCall.cpp
index 92d15d9..0d6a70c 100644
--- a/lib/CodeGen/CGCall.cpp
+++ b/lib/CodeGen/CGCall.cpp
@@ -38,6 +38,7 @@
   default: return llvm::CallingConv::C;
   case CC_X86StdCall: return llvm::CallingConv::X86_StdCall;
   case CC_X86FastCall: return llvm::CallingConv::X86_FastCall;
+  case CC_X86ThisCall: return llvm::CallingConv::X86_ThisCall;
   }
 }
 
@@ -97,6 +98,9 @@
   if (D->hasAttr<FastCallAttr>())
     return CC_X86FastCall;
 
+  if (D->hasAttr<ThisCallAttr>())
+    return CC_X86ThisCall;
+
   return CC_C;
 }