[PATCH v4] gdb: add a symbol* argument to get_return_value

[Six, Lancelot]

[AMD Official Use Only]

> Hi Lancelot,
>
> Every time I look I keep finding nits, sorry :(

No worry.

> I have the feeling that value_type is redundant with func_symbol, since the return value type initially comes from the symbol.  So I think we could remove value_type.  In fact, it might have been redundant already, since from `struct value *function`, you should also be able to get the function type.  But there may be edge cases I don't know about.

To be honest, I did have a similar impression about the function parameter.  Once you have the function symbol, you should be able to get a value containing the function address, so this parameter is probably also redundant.  The reason I did not make this change is because the function's address is obtained with a call to:

    struct value *function = read_var_value (func_symbol, NULL, frame);

Moving this call within get_return_value might mean we use a different FRAME argument (get_current_frame ()).  I do not expect it to change anything, but because I am not 100% sure, I did not change that.

> Do you think this change below (that builds on top of your patch) would work?  Tests gdb.*/*finish*.exp pass here.

I'll probably try to remove both the value* and type* arguments and see if I have any regression (unless anyone is aware on some edge cases where this can be problematic).

WDYT?

Thanks,
Lancelot.