Compiler Bug: V panic: sym: invalid type (typ=ast.Type(0x0 = 0) idx=0)

[UbadahJ]

Hi!

Just getting started with V language (with no prior experience with Go or similar languages) and I am having issues compiling this piece of code.

import json

struct Node[T] {
	value T
mut:
	next ?&Node[T] = none
}

struct LinkedList[T] {
mut:
	head ?Node[T]
}

fn (mut ll LinkedList[T]) push(n Node[T]) LinkedList[T] {
	if ll.head == none {
		ll.head = n
		return ll
	} else {
		mut node := ll.head or { panic('unreachable') }
		for node.next != none {
			node = *node.next or { panic('unreachable') }
		}
		node.next = &n
		return ll
	}
}

fn main() {
	mut ll := LinkedList[int]{}
	ll.push(Node[int]{value: 1})
	ll.push(Node[int]{value: 2})
	ll.push(Node[int]{value: 3})
	println(json.encode(ll))
}

$ v file.v

V panic: sym: invalid type (typ=ast.Type(0x0 = 0) idx=0). Compiler bug. This should never happen. Please report the bug using `v bug file.v`.

v hash: 23e385e
0   v                                   0x000000010d9956b1 v__ast__default_table_panic_handler + 33
1   v                                   0x000000010d995708 v__ast__Table_panic + 72
2   v                                   0x000000010d98e5c2 v__ast__Table_sym + 354
3   v                                   0x000000010da93618 v__gen__c__Gen_expr_with_tmp_var + 296
4   v                                   0x000000010db8202f v__gen__c__Gen_zero_struct_field + 1807
5   v                                   0x000000010db239c6 v__gen__c__Gen_struct_init + 13014
6   v                                   0x000000010da7bd07 v__gen__c__Gen_expr + 11399
7   v                                   0x000000010da7e316 v__gen__c__Gen_expr_with_cast + 7830
8   v                                   0x000000010da93b5e v__gen__c__Gen_expr_with_tmp_var + 1646
9   v                                   0x000000010db81d8f v__gen__c__Gen_zero_struct_field + 1135
10  v                                   0x000000010db239c6 v__gen__c__Gen_struct_init + 13014
11  v                                   0x000000010da7bd07 v__gen__c__Gen_expr + 11399
12  v                                   0x000000010da996ce v__gen__c__Gen_assign_stmt + 22542
13  v                                   0x000000010dae1653 v__gen__c__Gen_stmt + 467
14  v                                   0x000000010dae106c v__gen__c__Gen_stmts_with_tmp_var + 4284
15  v                                   0x000000010da92c5c v__gen__c__Gen_stmts + 92
16  v                                   0x000000010db3d7e2 v__gen__c__Gen_gen_fn_decl + 14258
17  v                                   0x000000010daeabcf v__gen__c__Gen_fn_decl + 2671
18  v                                   0x000000010dae1d9f v__gen__c__Gen_stmt + 2335
19  v                                   0x000000010dae106c v__gen__c__Gen_stmts_with_tmp_var + 4284
20  v                                   0x000000010da92c5c v__gen__c__Gen_stmts + 92
21  v                                   0x000000010dac73b8 v__gen__c__Gen_gen_file + 504
22  v                                   0x000000010dac6e45 v__gen__c__cgen_process_one_file_cb + 5285
23  v                                   0x000000010d97d21a sync__pool__process_in_thread + 122
24  v                                   0x000000010d8e6aa4 sync__pool__process_in_thread_thread_wrapper + 36
25  libsystem_pthread.dylib             0x00007ff80b325259 _pthread_start + 125
26  libsystem_pthread.dylib             0x00007ff80b320c7b thread_start + 15

The compiler asks to report the issue but it seems like there might be an issue with how I am writing the generic types.

Any help would be appreciated!