https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120673
--- Comment #4 from Gaius Mulley <gaius at gcc dot gnu.org> ---
$ cat cyclictypes4.mod
MODULE cyclictypes4 ;
TYPE
A = B ;
B = C ;
C = D ;
D = A ;
VAR
v: A ;
BEGIN
END cyclictypes4.
$ gm2 -c cyclictypes4.mod
cyclictypes4.mod:4:4: error: circular dependency error found when trying to
resolve ‘A’
4 | A = B ;
| ^
cyclictypes4.mod:5:4: error: circular dependency error found when trying to
resolve ‘B’
5 | B = C ;
| ^
cyclictypes4.mod:6:4: error: circular dependency error found when trying to
resolve ‘C’
6 | C = D ;
| ^
cyclictypes4.mod:7:4: error: circular dependency error found when trying to
resolve ‘D’
7 | D = A ;
| ^
cyclictypes4.mod:10:4: error: circular dependency error found when trying to
resolve ‘v’
10 | v: A ;
| ^~~~
