Fix an edge case with BinaryOperator's in -Wuninitialized.  Add testcases for
the other visitors as well.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@218366 91177308-0d34-0410-b5e6-96231b3b80d8
Fix the argument index error of __builtin___memccpy_chk

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

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@218367 91177308-0d34-0410-b5e6-96231b3b80d8