The real fix for this whole mess is to require the operand of the
alias to be a *GlobalValue* (not a general constant, including
constant exprs) but allow the operand and the alias type to be
unrelated.
This fixes PR4066
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70079 91177308-0d34-0410-b5e6-96231b3b80d8