visitor.types
}
+/// Replacement for expr_unreachable which generates intrinsics::unreachable()
+/// instead of unreachable!()
+fn expr_unreachable_intrinsic(cx: &ExtCtxt, sp: Span) -> P<Expr> {
+ let path = cx.std_path(&["intrinsics", "unreachable"]);
+ let call = cx.expr_call_global(
+ sp, path, vec![]);
+ let unreachable = cx.expr_block(P(ast::Block {
+ stmts: vec![],
+ expr: Some(call),
+ id: ast::DUMMY_NODE_ID,
+ rules: ast::BlockCheckMode::Unsafe(ast::CompilerGenerated),
+ span: sp }));
+
+ unreachable
+}
+
impl<'a> TraitDef<'a> {
pub fn expand(&self,
cx: &mut ExtCtxt,
//Since we know that all the arguments will match if we reach the match expression we
//add the unreachable intrinsics as the result of the catch all which should help llvm
//in optimizing it
- let path = cx.std_path(&["intrinsics", "unreachable"]);
- let call = cx.expr_call_global(
- sp, path, vec![]);
- let unreachable = cx.expr_block(P(ast::Block {
- stmts: vec![],
- expr: Some(call),
- id: ast::DUMMY_NODE_ID,
- rules: ast::BlockCheckMode::Unsafe(ast::CompilerGenerated),
- span: sp }));
- match_arms.push(cx.arm(sp, vec![cx.pat_wild(sp)], unreachable));
+ match_arms.push(cx.arm(sp, vec![cx.pat_wild(sp)], expr_unreachable_intrinsic(cx, sp)));
// Final wrinkle: the self_args are expressions that deref
// down to desired l-values, but we cannot actually deref
// derive Debug on such a type could here generate code
// that needs the feature gate enabled.)
- cx.expr_unreachable(sp)
+ expr_unreachable_intrinsic(cx, sp)
}
else {