In Ghidra headless, all functions have return type undefined

[ignatirabo]

In Ghidra headless (compiled from the master branch), I want to find all functions that return undefined (*) [16]. However, when I check the return type of all functions, they return /undefined of length 1 with description 'Undefined Byte'.

The thing that surprised me is that if I turn on the Decompiler Parameter ID analyzer, the types are now defined. My guess is that Decompiler Parameter ID is commiting the function signatures.

Assuming my guess is correct: how can I ensure that when I run my AbstractAnalyzer the function signatures are commited?
Or what else could be the case?

This is the function signature if I let Ghidra do it's thing:

/* DISPLAY WARNING: Type casts are NOT being printed */

undefined1 (*) [16] f(undefined1 (*param_1) [16])

{
  *param_1 = 0x0;
  return param_1;
}

Also something I noticed is that when I do have 'Decompiler Parameter ID' on, the return type of this function is not an instance of PointerDataType, neither ArrayDataType (which sounds wrong) and it has length 8, when I would assume it has length 16. Any explanation for this?

Thanks in advance.

[ignatirabo]

For the last comment I did, I realized now that I need to check whether the return type is an instance of Pointer and not PointerDataType.

[ReversingWithMe]

This is somewhat old topic, but how are you checking the type?

the functions return type and the decompiled return type would be disjoint until committed or paramID, but you can query for the decompiled type instead.

Unless you commit several functions, or use paramID which does that for you, the requested types will be incorrect with function.getReturnType, but just accepting all the default types isn't always a good choice. Decompiling all functions may take a long time if the binary you care about is large.

[ReversingWithMe]

A screenshot of a function named `sub_0010d150`, which has signature "long sub_0010d150(undefined8 param_1,undefined8 param_2,undefined8 param_3,undefined8 param_4, undefined8 param_5,code *param_6,char param_7)". In the jython interpreter panel at the bottom, when asking for function.getReturnType() we get undefined, since the disassembly hasn't been synced with the decompilation. A screenshot of a function named `sub_0010d150`, which has signature "long sub_0010d150(undefined8 param_1,undefined8 param_2,undefined8 param_3,undefined8 param_4, undefined8 param_5,code *param_6,char param_7)". When decompiling using DecompInterface, asking for function.getReturnType() we get `long` now.