Re: [RFC/RFA?] Should break FILE:LINENO skip prologue?

[Jim Blandy <jimb@codesourcery.com>]

Michael Snyder <msnyder at specifix.com> writes:
> On Sun, 2008-01-13 at 10:21 +0100, Mark Kettenis wrote:
>> > Date: Sun, 13 Jan 2008 06:21:36 +0200
>> > From: Eli Zaretskii <eliz@gnu.org>
>> > 
>> > > In Ada, as Joel said, this is not true.  *FUNCTION won't work
>> > 
>> > That's too bad: this is an important feature, so if we cannot make it
>> > work in all languages, we should at least document that.
>> 
>> This is exactly the reason why documenting *FUNCTION on its own is the
>> wrong thing to do.  What we implement in GDB is *EXPRESSION, where
>> EXPRESSION is an expression in the current language yielding an
>> address. 
>
> Mark, I don't think that is true -- at least it used to be not
> (damn English language...)
>
> When you say "break *<something>", the asterisk is NOT 
> interpreted by the expression parser -- it is interpreted
> by the break command, or more precisely, by the LINESPEC
> parser.

Mark is agreeing with you.  He said the syntax is:

    break *EXPRESSION

Since the * is written out explicitly, it is not part of EXPRESSION.
If Mark had wanted to indicate that the expression parser was handling
that *, he would have written

    break EXPRESSION

We're all in violent agreement that this isn't what GDB does at
present.  :) From decode_line_1:

  /* See if arg is *PC.  */

  if (**argptr == '*')
    return decode_indirect (argptr);

where:

  /* Decode arg of the form *PC.  */

  static struct symtabs_and_lines
  decode_indirect (char **argptr)
  {
    struct symtabs_and_lines values;
    CORE_ADDR pc;

    (*argptr)++;
    pc = parse_and_eval_address_1 (argptr);

    ...
  }