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BUG: AttributeError: 'NoneType' object has no attribute 'c'

See original GitHub issue

ghidra2dwarf.py> Running...
Traceback (most recent call last):
  File "/root/ghidra_scripts/ghidra2dwarf/ghidra2dwarf.py", line 499, in <module>
    add_debug_info()
  File "/root/ghidra_scripts/ghidra2dwarf/ghidra2dwarf.py", line 138, in add_debug_info
    add_function(cu, f, file_index)
  File "/root/ghidra_scripts/ghidra2dwarf/ghidra2dwarf.py", line 318, in add_function
    d = res.decompiledFunction.c
AttributeError: 'NoneType' object has no attribute 'c'
ghidra2dwarf.py> Finished!

I’m new to Ghidra, so idk if my solution is right, but I found in docs that api got getC method.

and try to fix:


def add_function(cu, func, file_index):
    die = dwarf_new_die(dbg, DW_TAG_subprogram, cu, None, None, None)
    loc_expr = dwarf_new_expr(dbg)
    dwarf_add_expr_gen(loc_expr, DW_OP_call_frame_cfa, 0, 0)
    dwarf_add_AT_location_expr(dbg, die, DW_AT_frame_base, loc_expr)
    f_name = func.name
    dwarf_add_AT_name(die, f_name)
    dwarf_add_AT_string(dbg, die, DW_AT_linkage_name, f_name)

    # TODO: Check for multiple ranges
    f_start, f_end = get_function_range(func)

    t = func.returnType
    ret_type_die = add_type(cu, func.returnType)
    dwarf_add_AT_reference(dbg, die, DW_AT_type, ret_type_die)

    dwarf_add_AT_targ_address(dbg, die, DW_AT_low_pc, f_start, 0)
    dwarf_add_AT_targ_address(dbg, die, DW_AT_high_pc, f_end - 1, 0)

    func_line = len(decomp_lines) + 1

    res = get_decompiled_function(func)
    if res:
        try:
            d = res.decompiledFunction.c
        except:
            d = res.decompiledFunction.getC
    else:
        return

    decomp_lines.extend(d.split("\n"))
    dwarf_add_AT_unsigned_const(dbg, die, DW_AT_decl_file, file_index)
    dwarf_add_AT_unsigned_const(dbg, die, DW_AT_decl_line, func_line)
    dwarf_add_line_entry(dbg, file_index, f_start, func_line, 0, True, False)
    add_decompiler_func_info(cu, die, func, file_index, func_line)

    return die

But, no luck:

ghidra2dwarf.py> Running...
Traceback (most recent call last):
  File "/root/ghidra_scripts/ghidra2dwarf/ghidra2dwarf.py", line 505, in <module>
    add_debug_info()
  File "/root/ghidra_scripts/ghidra2dwarf/ghidra2dwarf.py", line 138, in add_debug_info
    add_function(cu, f, file_index)
  File "/root/ghidra_scripts/ghidra2dwarf/ghidra2dwarf.py", line 322, in add_function
    d = res.decompiledFunction.getC
AttributeError: 'NoneType' object has no attribute 'getC'
ghidra2dwarf.py> Finished!

I found this in api docs:

   
   // Make calls to the decompiler:
   DecompileResults res = ifc.decompileFunction(func,0,taskmonitor);
   
   // Check for error conditions
   if (!res.decompileCompleted()) {
        system.out.println(res.getErrorMessage());
      return;
   }