diff --git a/lib/Target/X86/X86FastISel.cpp b/lib/Target/X86/X86FastISel.cpp
index 13e20f4eb0e..952cd6011fe 100644
--- a/lib/Target/X86/X86FastISel.cpp
+++ b/lib/Target/X86/X86FastISel.cpp
@@ -1576,10 +1576,11 @@ bool X86FastISel::DoSelectCall(const Instruction *I, const char *MemIntName) {
   SmallVector<unsigned, 8> Args;
   SmallVector<MVT, 8> ArgVTs;
   SmallVector<ISD::ArgFlagsTy, 8> ArgFlags;
-  Args.reserve(CS.arg_size());
-  ArgVals.reserve(CS.arg_size());
-  ArgVTs.reserve(CS.arg_size());
-  ArgFlags.reserve(CS.arg_size());
+  unsigned arg_size = CS.arg_size();
+  Args.reserve(arg_size);
+  ArgVals.reserve(arg_size);
+  ArgVTs.reserve(arg_size);
+  ArgFlags.reserve(arg_size);
   for (ImmutableCallSite::arg_iterator i = CS.arg_begin(), e = CS.arg_end();
        i != e; ++i) {
     // If we're lowering a mem intrinsic instead of a regular call, skip the