commit 21b42af5aa6bc25dd99d2e425aa3df6bac80476e (tree)
parent a226008e32af8700d1aa05bcaef50cb3cf1205d0
Author: Matthew Lugg <mlugg@mlugg.co.uk>
Date: Sun, 8 Feb 2026 14:58:32 +0000
tests: update for accepted language change
`@sizeOf` and `@bitSizeOf` are now more restricted: they are not allowed
on comptime-only or NPV (uninstantiable) types. This is because there is
no correct way to actually use the returned ABI size (e.g. you cannot
copy a comptime-only type by copying all of its runtime bits), so having
a non-zero return value had no benefit and was simply confusing.
Diffstat:
4 files changed, 30 insertions(+), 31 deletions(-)
diff --git a/test/behavior/sizeof_and_typeof.zig b/test/behavior/sizeof_and_typeof.zig
@@ -11,13 +11,6 @@ test "@sizeOf and @TypeOf" {
const x: u16 = 13;
const z: @TypeOf(x) = 19;
-test "@sizeOf on compile-time types" {
- try expect(@sizeOf(comptime_int) == 0);
- try expect(@sizeOf(comptime_float) == 0);
- try expect(@sizeOf(@TypeOf(.hi)) == 0);
- try expect(@sizeOf(@TypeOf(type)) == 0);
-}
-
test "@TypeOf() with multiple arguments" {
{
var var_1: u32 = undefined;
@@ -265,10 +258,6 @@ test "lazy size cast to float" {
}
}
-test "bitSizeOf comptime_int" {
- try expect(@bitSizeOf(comptime_int) == 0);
-}
-
test "runtime instructions inside typeof in comptime only scope" {
if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest;
if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest; // TODO
@@ -336,20 +325,6 @@ test "peer type resolution with @TypeOf doesn't trigger dependency loop check" {
try std.testing.expect(t.next == null);
}
-test "@sizeOf reified union zero-size payload fields" {
- comptime {
- try std.testing.expect(0 == @sizeOf(@Union(.auto, null, &.{}, &.{}, &.{})));
- try std.testing.expect(0 == @sizeOf(@Union(.auto, null, &.{"a"}, &.{void}, &.{.{}})));
- if (builtin.mode == .Debug or builtin.mode == .ReleaseSafe) {
- try std.testing.expect(1 == @sizeOf(@Union(.auto, null, &.{ "a", "b" }, &.{ void, void }, &.{ .{}, .{} })));
- try std.testing.expect(1 == @sizeOf(@Union(.auto, null, &.{ "a", "b", "c" }, &.{ void, void, void }, &.{ .{}, .{}, .{} })));
- } else {
- try std.testing.expect(0 == @sizeOf(@Union(.auto, null, &.{ "a", "b" }, &.{ void, void }, &.{ .{}, .{} })));
- try std.testing.expect(0 == @sizeOf(@Union(.auto, null, &.{ "a", "b", "c" }, &.{ void, void, void }, &.{ .{}, .{}, .{} })));
- }
- }
-}
-
const FILE = extern struct {
dummy_field: u8,
};
diff --git a/test/behavior/type.zig b/test/behavior/type.zig
@@ -278,13 +278,13 @@ test "Type.Union from regular enum" {
test "Type.Union from empty regular enum" {
const E = enum {};
const U = @Union(.auto, E, &.{}, &.{}, &.{});
- try testing.expectEqual(@sizeOf(U), 0);
+ try testing.expectEqual(@typeInfo(U).@"union".fields.len, 0);
}
test "Type.Union from empty Type.Enum" {
const E = @Enum(u0, .exhaustive, &.{}, &.{});
const U = @Union(.auto, E, &.{}, &.{}, &.{});
- try testing.expectEqual(@sizeOf(U), 0);
+ try testing.expectEqual(@typeInfo(U).@"union".fields.len, 0);
}
test "Type.Fn" {
diff --git a/test/cases/compile_errors/alignOf_bad_type.zig b/test/cases/compile_errors/alignOf_bad_type.zig
@@ -1,7 +1,13 @@
-export fn entry() usize {
+export fn entry0() usize {
return @alignOf(noreturn);
}
+const S = struct { a: u32, b: noreturn };
+export fn entry1() usize {
+ return @alignOf(S);
+}
// error
//
-// :2:21: error: no align available for type 'noreturn'
+// :2:21: error: no align available for uninstantiable type 'noreturn'
+// :6:21: error: no align available for uninstantiable type 'alignOf_bad_type.S'
+// :4:11: note: struct declared here
diff --git a/test/cases/compile_errors/sizeOf_bad_type.zig b/test/cases/compile_errors/sizeOf_bad_type.zig
@@ -1,7 +1,25 @@
-export fn entry() usize {
+export fn entry0() usize {
return @sizeOf(@TypeOf(null));
}
+export fn entry1() usize {
+ return @sizeOf(comptime_int);
+}
+export fn entry2() usize {
+ return @sizeOf(noreturn);
+}
+const S3 = struct { a: u32, b: comptime_int };
+export fn entry3() usize {
+ return @sizeOf(S3);
+}
+const S4 = struct { a: u32, b: noreturn };
+export fn entry4() usize {
+ return @sizeOf(S4);
+}
// error
//
-// :2:20: error: no size available for type '@TypeOf(null)'
+// :2:20: error: no size available for comptime-only type '@TypeOf(null)'
+// :5:20: error: no size available for comptime-only type 'comptime_int'
+// :8:20: error: no size available for uninstantiable type 'noreturn'
+// :12:20: error: no size available for comptime-only type 'tmp.S3'
+// :16:20: error: no size available for uninstantiable type 'tmp.S4'
