Uninitialized memory treated as poison

[nikic]

It looks like alive2 is treating uninitialized memory as poison: https://alive2.llvm.org/ce/z/VKRwvf

define i8 @src() {
  %a = alloca i8, align 1
  %v = load i8, ptr %a, align 1
  ret i8 %v
}

define i8 @tgt() {
  ret i8 poison
}

This doesn't match LLVM's current semantics.

[IamYJLee]

@nikic @nunoplopes I would like to try to fix this problem. Could I get some help to do so?

[nunoplopes]

First of all, it's not an easy fix. Secondly, I'm trying to fix LLVM rather than fixing Alive2 🙂 Hopefully we can fix LLVM instead in the next few months.