make transparent enums more ordinary

This commit is contained in:
Mazdak Farrokhzad 2019-12-15 15:11:34 +01:00
parent a605441e04
commit 5d73af2d4c

View File

@ -2330,7 +2330,7 @@ fn bad_variant_count<'tcx>(tcx: TyCtxt<'tcx>, adt: &'tcx ty::AdtDef, sp: Span, d
);
let mut err = struct_span_err!(tcx.sess, sp, E0731, "transparent enum {}", msg);
err.span_label(sp, &msg);
if let &[ref start @ .., ref end] = &variant_spans[..] {
if let [start @ .., end] = &*variant_spans {
for variant_span in start {
err.span_label(*variant_span, "");
}
@ -2372,23 +2372,14 @@ fn check_transparent(tcx: TyCtxt<'_>, sp: Span, def_id: DefId) {
}
let sp = tcx.sess.source_map().def_span(sp);
if adt.is_enum() {
if !tcx.features().transparent_enums {
feature_err(
&tcx.sess.parse_sess,
sym::transparent_enums,
sp,
"transparent enums are unstable",
)
.emit();
}
if adt.variants.len() != 1 {
bad_variant_count(tcx, adt, sp, def_id);
if adt.variants.is_empty() {
// Don't bother checking the fields. No variants (and thus no fields) exist.
return;
}
}
if adt.is_enum() && !tcx.features().transparent_enums {
feature_err(
&tcx.sess.parse_sess,
sym::transparent_enums,
sp,
"transparent enums are unstable",
)
.emit();
}
if adt.is_union() && !tcx.features().transparent_unions {
@ -2401,6 +2392,14 @@ fn check_transparent(tcx: TyCtxt<'_>, sp: Span, def_id: DefId) {
.emit();
}
if adt.variants.len() != 1 {
bad_variant_count(tcx, adt, sp, def_id);
if adt.variants.is_empty() {
// Don't bother checking the fields. No variants (and thus no fields) exist.
return;
}
}
// For each field, figure out if it's known to be a ZST and align(1)
let field_infos = adt.all_fields().map(|field| {
let ty = field.ty(tcx, InternalSubsts::identity_for_item(tcx, field.did));