Not implemented at types.rs:1837 (Solang v0.3.4 --target solana)

[ZeroReR]

Describe the bug
solang panics when a user-defined value type appears as a struct member.

To Reproduce
This code compiles successfully with solc, but panics with solang v0.3.4 --target solana.

type C is address;
struct S { C c; }
contract T { S s; }

Expected behavior
Either compile or emit a diagnostic instead of an internal panic.

Screenshots
If applicable, add screenshots to help explain your problem.

Hyperledger Solang version
Solang v0.3.4 --traget Solana

Include the complete solidity source code

type C is address;
struct S { C c; }
contract T { S s; }

Additional context

[mansiverma897993]

can you assign me this or I can directly raise PR here ?