also use *idx_begin in the same expression, giving unpredictable results. This fixes this bug: http://lists.cs.uiuc.edu/pipermail/llvmdev/2008-July/015877.html git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53670 91177308-0d34-0410-b5e6-96231b3b80d8