[Bug rtl-optimization/81194] [8 Regression] ICE during RTL pass: expand

["bergner at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81194

Peter Bergner <bergner at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED
           Assignee|unassigned at gcc dot gnu.org      |bergner at gcc dot gnu.org

--- Comment #8 from Peter Bergner <bergner at gcc dot gnu.org> ---
So we have a switch statement with onc case and a default case statement.  The
normal case statement contains an __builtin_unreachable() call, so we delete
the case statement, leaving us with only the default case.  We then call into
expand_case() and we have this code which has been there for a while:

  /* Get upper and lower bounds of case values.  */
  elt = gimple_switch_label (stmt, 1);

Since there is only one default case statement in stmt, asking for the label at
offset "1" is illegal and that leads to the ICE.  Either we need to protect
this code or maybe we can remove the switch statement all together.