CPP serialize always return empty string and cached size is 0 but i can get data

[Thomas Colin]

Hello I've got some troubles because when I build a message and try to serialize it, the func serializeToString return true but the string is empty and if I get the mutables values of my message it gives me the good values some ideas ? btw i'm using protobuf 3.15.8

[Thomas Colin]

here are some screenshots

code : 

breakpoint info :