src/test/mir-opt/issues/issue_75439.rs

   1 // EMIT_MIR issue_75439.foo.MatchBranchSimplification.diff
   2
   3 use std::mem::transmute;
   4
   5 pub fn foo(bytes: [u8; 16]) -> Option<[u8; 4]> {
   6     // big endian `u32`s
   7     let dwords: [u32; 4] = unsafe { transmute(bytes) };
   8     const FF: u32 = 0x0000_ffff_u32.to_be();
   9     if let [0, 0, 0 | FF, ip] = dwords {
  10         Some(unsafe { transmute(ip) })
  11     } else {
  12         None
  13     }
  14 }
  15
  16 fn main() {
  17     let _ = foo([0; 16]);
  18 }