resolve some TODOs

Author: Vexu

src/Sema.zig

@@ -3319,8 +3319,6 @@ fn zirEnsureErrUnionPayloadVoid(sema: *Sema, block: *Block, inst: Zir.Inst.Index
         operand_ty.childType()
     else
         operand_ty;
-    // TODO this should be validated in a more generic instruction that is
-    // emitted for all ifs and whiles with an error union condition.
     if (err_union_ty.zigTypeTag() != .ErrorUnion) return;
     const payload_ty = err_union_ty.errorUnionPayload().zigTypeTag();
     if (payload_ty != .Void and payload_ty != .NoReturn) {
@@ -21596,7 +21594,7 @@ fn zirVarExtended(
         .owner_decl = sema.owner_decl_index,
         .init = init_val,
         .is_extern = small.is_extern,
-        .is_mutable = true, // TODO get rid of this unused field
+        .is_mutable = true,
         .is_threadlocal = small.is_threadlocal,
         .is_weak_linkage = false,
         .lib_name = null,
@@ -22075,7 +22073,7 @@ fn zirBuiltinExtern(
         .owner_decl = sema.owner_decl_index,
         .init = Value.initTag(.unreachable_value),
         .is_extern = true,
-        .is_mutable = false, // TODO get rid of this unused field
+        .is_mutable = false,
         .is_threadlocal = options.is_thread_local,
         .is_weak_linkage = options.linkage == .Weak,
         .lib_name = null,

src/Zir.zig

@@ -100,8 +100,7 @@ pub fn nullTerminatedString(code: Zir, index: usize) [:0]const u8 {
 
 pub fn refSlice(code: Zir, start: usize, len: usize) []Inst.Ref {
     const raw_slice = code.extra[start..][0..len];
-    // TODO we should be able to directly `@ptrCast` the slice to the other slice type.
-    return @ptrCast([*]Inst.Ref, raw_slice.ptr)[0..len];
+    return @ptrCast([]Inst.Ref, raw_slice);
 }
 
 pub fn hasCompileErrors(code: Zir) bool {

src/main.zig

@@ -3412,8 +3412,7 @@ fn runOrTest(
                         } else if (watch) {
                             warn("process exited with code {d}", .{code});
                         } else {
-                            // TODO https://github.com/ziglang/zig/issues/6342
-                            process.exit(1);
+                            process.exit(code);
                         }
                     },
                     else => {

src/type.zig

@@ -1236,7 +1236,7 @@ pub const Type = extern union {
             // we can't hash these based on tags because they wouldn't match the expanded version.
             .type_info => unreachable, // needed to resolve the type before now
 
-            .bound_fn => unreachable, // TODO delete from the language
+            .bound_fn => unreachable,
             .var_args_param => unreachable, // can be any type
         }
     }
@@ -3272,7 +3272,7 @@ pub const Type = extern union {
             .fn_ccc_void_no_args => unreachable, // represents machine code; not a pointer
             .function => unreachable, // represents machine code; not a pointer
             .@"opaque" => unreachable, // no size available
-            .bound_fn => unreachable, // TODO remove from the language
+            .bound_fn => unreachable,
             .noreturn => unreachable,
             .inferred_alloc_const => unreachable,
             .inferred_alloc_mut => unreachable,
@@ -4088,47 +4088,6 @@ pub const Type = extern union {
         }
     }
 
-    /// Returns if type can be used for a runtime variable
-    pub fn isValidVarType(self: Type, is_extern: bool) bool {
-        var ty = self;
-        while (true) switch (ty.zigTypeTag()) {
-            .Bool,
-            .Int,
-            .Float,
-            .ErrorSet,
-            .Enum,
-            .Frame,
-            .AnyFrame,
-            => return true,
-
-            .Opaque => return is_extern,
-            .ComptimeFloat,
-            .ComptimeInt,
-            .EnumLiteral,
-            .NoReturn,
-            .Type,
-            .Void,
-            .Undefined,
-            .Null,
-            => return false,
-
-            .Optional => {
-                var buf: Payload.ElemType = undefined;
-                return ty.optionalChild(&buf).isValidVarType(is_extern);
-            },
-            .Pointer, .Array, .Vector => ty = ty.elemType(),
-            .ErrorUnion => ty = ty.errorUnionPayload(),
-
-            .Fn => @panic("TODO fn isValidVarType"),
-            .Struct => {
-                // TODO this is not always correct; introduce lazy value mechanism
-                // and here we need to force a resolve of "type requires comptime".
-                return true;
-            },
-            .Union => @panic("TODO union isValidVarType"),
-        };
-    }
-
     /// For *[N]T,  returns [N]T.
     /// For *T,     returns T.
     /// For [*]T,   returns T.
@@ -5434,7 +5393,6 @@ pub const Type = extern union {
     }
 
     /// Asserts the type is an enum or a union.
-    /// TODO support unions
     pub fn intTagType(ty: Type, buffer: *Payload.Bits) Type {
         switch (ty.tag()) {
             .enum_full, .enum_nonexhaustive => return ty.cast(Payload.EnumFull).?.data.tag_ty,

src/value.zig

@@ -814,7 +814,6 @@ pub const Value = extern union {
             .float_80 => return out_stream.print("{}", .{val.castTag(.float_80).?.data}),
             .float_128 => return out_stream.print("{}", .{val.castTag(.float_128).?.data}),
             .@"error" => return out_stream.print("error.{s}", .{val.castTag(.@"error").?.data.name}),
-            // TODO to print this it should be error{ Set, Items }!T(val), but we need the type for that
             .eu_payload => {
                 try out_stream.writeAll("(eu_payload) ");
                 val = val.castTag(.eu_payload).?.data;
@@ -989,8 +988,7 @@ pub const Value = extern union {
         switch (val.tag()) {
             .enum_field_index => {
                 const field_index = val.castTag(.enum_field_index).?.data;
-                // TODO should `@intToEnum` do this `@intCast` for you?
-                return @intToEnum(E, @intCast(@typeInfo(E).Enum.tag_type, field_index));
+                return @intToEnum(E, field_index);
             },
             .the_only_possible_value => {
                 const fields = std.meta.fields(E);