Compiler segfault on mutually recursive structs

[MrMugame]

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Zig Version

0.12.0

Steps to Reproduce and Observed Behavior

test.zig

const struct_A = struct {
    b: struct_B,
};

const struct_B = struct {
    a: struct_A,
};

pub fn main() void {
    const s: struct_B = undefined;
    _ = s;
}

Run with: zig run test.zig

This results in the compiler to segfault: [1] 59758 segmentation fault (core dumped) zig run test.zig

Expected Behavior

I expected the compiler to throw an error message on mutually recursive structs not being allowed, instead it segfaults.

[Rexicon226]

The segfault happens because of infinite recursion in the compiler. Related #13724.

Back trace:

....
frame #18132: 0x0000000008955669 zig`type.Type.hasRuntimeBitsAdvanced at type.zig:585:64
frame #18133: 0x0000000008955669 zig`type.Type.hasRuntimeBitsAdvanced at type.zig:585:64
frame #18134: 0x0000000008955669 zig`type.Type.hasRuntimeBitsAdvanced at type.zig:585:64
frame #18135: 0x0000000008955669 zig`type.Type.hasRuntimeBitsAdvanced at type.zig:585:64
frame #18136: 0x0000000008955669 zig`type.Type.hasRuntimeBitsAdvanced at type.zig:585:64
frame #18137: 0x000000000851cab3 zig`Sema.typeHasRuntimeBits at Sema.zig:37679:37
frame #18138: 0x0000000009c55225 zig`Sema.addDbgVar at Sema.zig:6747:38
frame #18139: 0x00000000094b2f84 zig`Sema.zirDbgVar at Sema.zig:6727:23
frame #18140: 0x0000000008df6bce zig`Sema.analyzeBodyInner at Sema.zig:1317:35
frame #18141: 0x0000000008816252 zig`Sema.analyzeFnBody at Sema.zig:892:26

[tau-dev]

Can reproduce on 0.13.0, seems to be fixed on latest master.