NationalSecurityAgency/ghidra · warning · ValueError

Conversion of string arrays unimplemented

Error message

Conversion of string arrays unimplemented

What it means

Thrown as a ValueError during type conversion in the gdb agent when a gdb.Value has type code gdb.TYPE_CODE_STRING inside an array context. The code explicitly raises this because conversion of Pascal-style string arrays (common in Fortran/Ada) to Ghidra trace values has not been implemented yet. The TODO comment confirms this is a known gap.

Source

Thrown at Ghidra/Debug/Debugger-agent-gdb/src/main/py/src/ghidragdb/commands.py:845

                        return to_string(val, type, 'utf-16', full=False), sch.STRING
                    schema = sch.SHORT_ARR
                elif schema == sch.CHAR_ARR:
                    return to_string(val, type, 'utf-16', full=True), schema
                return to_int_list(val, type), schema
            elif etype.sizeof == 4:
                if schema is None:
                    if etype.name == 'wchar_t':
                        return to_string(val, type, 'utf-32', full=False), sch.STRING
                    schema = sch.INT_ARR
                elif schema == sch.CHAR_ARR:
                    return to_string(val, type, 'utf-32', full=True), schema
                return to_int_list(val, type), schema
            elif schema is not None:
                return to_int_list(val, type), schema
            elif etype.sizeof == 8:
                return to_int_list(val, type), sch.LONG_ARR
        elif etype.code == gdb.TYPE_CODE_STRING:
            raise ValueError("Conversion of string arrays unimplemented")
        # TODO: Array of C strings?
    elif type.code == gdb.TYPE_CODE_STRING:
        return val.string(), sch.STRING
    elif type.code == gdb.TYPE_CODE_PTR:
        offset = int(val)
        inf = gdb.selected_inferior()
        base, addr = STATE.require_trace().extra.require_mm().map(inf, offset)
        return (base, addr), sch.ADDRESS
    raise ValueError(f"Cannot convert ({schema}): '{value}', value='{val}'")


@cmd('ghidra trace set-value', '-ghidra-trace-set-value', gdb.COMMAND_DATA, True)
def ghidra_trace_set_value(path: str, key: str, value: str,
                           schema: Optional[str] = None, *, is_mi: bool,
                           **kwargs) -> None:
    """Set a value (attribute or element) in the Ghidra trace's object tree.

    A void value implies removal. NOTE: The type of an expression may be

View on GitHub (pinned to d5f144c24d)

Solutions

  1. Avoid setting trace values for string-array typed variables — this conversion is unimplemented.
  2. If the value is a simple string (not an array), access it via val.string() outside the array branch.
  3. Convert the value to a byte array or int list manually before passing to the trace API.
  4. File a feature request with the Ghidra project for TYPE_CODE_STRING array support.
Defensive patterns

Strategy: try-catch

Validate before calling

def is_string_array_value(val: gdb.Value) -> bool:
    try:
        t = val.type.strip_typedefs()
        if t.code == gdb.TYPE_CODE_ARRAY:
            etype = t.target()
            if etype.code == gdb.TYPE_CODE_STRING:
                return True
    except Exception:
        pass
    return False

Type guard

def is_convertible_value(val: gdb.Value) -> bool:
    try:
        t = val.type.strip_typedefs()
        if t.code == gdb.TYPE_CODE_ARRAY:
            etype = t.target()
            if etype.code == gdb.TYPE_CODE_STRING:
                return False
        return True
    except Exception:
        return False

Try / catch

try:
    result = convert_value(val, type, schema)
except ValueError as e:
    if 'string arrays unimplemented' in str(e):
        print('TYPE_CODE_STRING array conversion is not supported. Skipping this value.')
        result = None
    else:
        raise

Prevention

When it happens

Trigger: Calling ghidra_trace_set_value or any value-conversion path with a gdb.Value whose dynamic type has code gdb.TYPE_CODE_STRING within an array. This occurs primarily when debugging Fortran or Ada programs that use fixed-length string arrays, or when evaluating expressions that yield such types.

Common situations: Debugging Fortran CHARACTER arrays, Ada string types, or Pascal STRING arrays; setting a value on a variable whose type resolves to TYPE_CODE_STRING in an array context; evaluating an expression in a mixed-language session.

Related errors

AI-assisted analysis of NationalSecurityAgency/ghidra@d5f144c24d (2026-08-14). Data as JSON: /api/errors/840fa2dba3ec6308. Report an issue: GitHub.