Fix the argument index error of __builtin___memccpy_chk

memccpy_check should have source and dest size at arg 3 and 4
rdar://18431336

llvm-svn: 218367
diff --git a/clang/lib/Sema/SemaChecking.cpp b/clang/lib/Sema/SemaChecking.cpp
index 7462869..5ea862c 100644
--- a/clang/lib/Sema/SemaChecking.cpp
+++ b/clang/lib/Sema/SemaChecking.cpp
@@ -365,7 +365,6 @@
   // check secure string manipulation functions where overflows
   // are detectable at compile time
   case Builtin::BI__builtin___memcpy_chk:
-  case Builtin::BI__builtin___memccpy_chk:
   case Builtin::BI__builtin___memmove_chk:
   case Builtin::BI__builtin___memset_chk:
   case Builtin::BI__builtin___strlcat_chk:
@@ -375,6 +374,9 @@
   case Builtin::BI__builtin___stpncpy_chk:
     SemaBuiltinMemChkCall(*this, FDecl, TheCall, 2, 3);
     break;
+  case Builtin::BI__builtin___memccpy_chk:
+    SemaBuiltinMemChkCall(*this, FDecl, TheCall, 3, 4);
+    break;
   case Builtin::BI__builtin___snprintf_chk:
   case Builtin::BI__builtin___vsnprintf_chk:
     SemaBuiltinMemChkCall(*this, FDecl, TheCall, 1, 3);