fix warning when assertions disabled.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52589 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/IntervalPartition.cpp b/lib/Analysis/IntervalPartition.cpp
index a430cff..2d5f1cd 100644
--- a/lib/Analysis/IntervalPartition.cpp
+++ b/lib/Analysis/IntervalPartition.cpp
@@ -91,8 +91,7 @@
 //
 IntervalPartition::IntervalPartition(IntervalPartition &IP, bool)
   : FunctionPass((intptr_t) &ID) {
-  Interval *FunctionStart = IP.getRootInterval();
-  assert(FunctionStart && "Cannot operate on empty IntervalPartitions!");
+  assert(IP.getRootInterval() && "Cannot operate on empty IntervalPartitions!");
 
   // Pass false to intervals_begin because we take ownership of it's memory
   interval_part_interval_iterator I = intervals_begin(IP, false);