Stack overflow in Type_binary.Decode (?)

[smondet]

This happened with Tezos v15.1 (old version) which uses repr 0.6.1
(see here)

Reporting here in case it helps because I see a non-tail-recursive function at
type_binary.ml:172 but maybe the stack trace is just messed up (or the outer List.map is the culprit?).

Thread 2 killed on uncaught exception Stack_overflow
Raised by primitive operation at Repr__Binary.Mono_container.decode.sub in file "src/repr/binary.ml", line 232, characters 18-34
Called from Repr__Type_binary.Decode.map.(fun) in file "src/repr/type_binary.ml", line 211, characters 32-56
Called from Index__Data.Entry.Make.decode_key in file "src/data.ml", line 79, characters 16-35
Called from Index__Log_file.Make.key_of_offset in file "src/log_file.ml", line 74, characters 8-68
Called from Index__Log_file.Make.replace_memory.(fun) in file "src/log_file.ml", line 128, characters 25-56
Called from Stdlib__List.map in file "list.ml", line 92, characters 20-23
Called from Stdlib__List.map in file "list.ml", line 92, characters 32-39
Called from Stdlib__List.map in file "list.ml", line 92, characters 32-39