False dependency loop with function pointer

[mitchellh]

Zig Version

0.11.0-dev.1329+37424fd11

Steps to Reproduce and Observed Behavior

zig test test.zig:

pub const A = struct {
    field: B = undefined,
};

pub const B = struct {
    field: *const fn (*A) void,
};

test {
    var a: usize = @sizeOf(B);
    _ = a;
}

Some notes:

• Must be runtime, comptime works fine (var vs const)
• Must be function pointer, regular pointer to *A works fine
• Must have initializer on A's field

Expected Behavior

No error.

[mitchellh]

Maybe a dup of the following, but they seemed slightly different:

#14147
#12325

[nektro]

michal-z's reduction in 12325 is the same as yours

[mitchellh]

Yeah, perhaps it is. There are some weird properties of mine I wasn't sure about and the shape didn't feel identical. For example, if you get rid of the initializer = undefined in mine, it works.

[nektro]

if you remove the = undefined and change the test to @sizeOf(A) does it crash? i think that might be another difference between the two

[mitchellh]

if you remove the = undefined and change the test to @sizeOf(A) does it crash? i think that might be another difference between the two

That also works fine (doesn't produce compiler error).

[perillo]

@mitchellh It seems the bug has been fixed, since with 0.12.0-dev.2341+92211135 the test runs correctly.

[Vexu]

It triggers an assertion failure with a debug build.