```mermaid
flowchart TD
    Start([Function Called]) --> CheckErr{Did an error occur?}

    %% Error path
    CheckErr -->|Yes| PushBit["Bitwise OR error code into err<br/>err |= ERROR_BIT"]
    PushBit --> CheckOrigin{Is origin == NULL?}
    CheckOrigin -->|Yes| SetOrigin["Record location in origin<br/>origin = __func__ / __FILE__"]
    CheckOrigin -->|No| KeepOrigin[Preserve original root cause]

    SetOrigin --> ReturnStruct
    KeepOrigin --> ReturnStruct

    %% Success / Normal path
    CheckErr -->|No| ComputeValue["Write computation result<br/>value = result"]
    ComputeValue --> ReturnStruct

    ReturnStruct(["Return / Pass Out _err_t"]) --> Caller{Caller Inspection}

    Caller -->|Check errors| InspectBits[Inspect bit flags in err]
    Caller -->|Read payload| ReadValue[Access value data]
    Caller -->|Debug / Log| PrintOrigin[Print root cause origin]
```