authorgravatar for david@vortan.devDavid Rubin <david@vortan.dev> 2024-02-06 11:04:09-08:00
committergravatar for noreply@github.comGitHub <noreply@github.com> 2024-02-06 21:04:09+02:00
log24fb6d1f301ee44bbfe865a6130c038094c32b60
treef1b5548dc278da43a173d4eeb54346d817f5d187
parent52066bf8e4855e610754603cbcc64dbfd16796fe
signaturebadge-check Signed by PGP key B5690EEEBB952194

Make `@intFromEnum` an error for empty enums

2 files changed, 26 insertions(+), 1 deletions(-)

src/Sema.zig+14-1
......@@ -8629,6 +8629,7 @@ fn zirIntFromEnum(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError
86298629 .{src},
86308630 );
86318631 };
8632
86328633 break :blk try sema.unionToTag(block, tag_ty, operand, operand_src);
86338634 },
86348635 else => {
......@@ -8638,14 +8639,25 @@ fn zirIntFromEnum(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError
86388639 },
86398640 };
86408641 const enum_tag_ty = sema.typeOf(enum_tag);
8641
86428642 const int_tag_ty = enum_tag_ty.intTagType(mod);
86438643
8644 // TODO: use correct solution
8645 // https://github.com/ziglang/zig/issues/15909
8646 if (enum_tag_ty.enumFieldCount(mod) == 0 and !enum_tag_ty.isNonexhaustiveEnum(mod)) {
8647 return sema.fail(block, operand_src, "cannot use @intFromEnum on empty enum '{}'", .{
8648 enum_tag_ty.fmt(mod),
8649 });
8650 }
8651
86448652 if (try sema.typeHasOnePossibleValue(enum_tag_ty)) |opv| {
86458653 return Air.internedToRef((try mod.getCoerced(opv, int_tag_ty)).toIntern());
86468654 }
86478655
86488656 if (try sema.resolveValue(enum_tag)) |enum_tag_val| {
8657 if (enum_tag_val.isUndef(mod)) {
8658 return mod.undefRef(int_tag_ty);
8659 }
8660
86498661 const val = try enum_tag_val.intFromEnum(enum_tag_ty, mod);
86508662 return Air.internedToRef(val.toIntern());
86518663 }
......@@ -20944,6 +20956,7 @@ fn zirTagName(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError!Air
2094420956 if (enum_ty.enumFieldCount(mod) == 0) {
2094520957 // TODO I don't think this is the correct way to handle this but
2094620958 // it prevents a crash.
20959 // https://github.com/ziglang/zig/issues/15909
2094720960 return sema.fail(block, operand_src, "cannot get @tagName of empty enum '{}'", .{
2094820961 enum_ty.fmt(mod),
2094920962 });
test/cases/compile_errors/int_from_enum_undefined.zig created+12
......@@ -0,0 +1,12 @@
1export fn a() void {
2 const E = enum {};
3 var e: E = undefined;
4 _ = &e;
5 _ = @intFromEnum(e);
6}
7
8// error
9// backend=stage2
10// target=native
11//
12// :5:22: error: cannot use @intFromEnum on empty enum 'tmp.a.E'