Adding -file-list-exec-source-file command to GDB/MI

[Andrew Cagney]

> On Fri, Mar 21, 2003 at 01:55:32AM -0800, Jason Molenda wrote:
> 
>> Hello Bob,
>> 
>> My approval isn't needed for these patches or anything, I'm just
>> an interested observer making comments.
>> 
>> On Thu, Mar 20, 2003 at 05:44:54PM -0500, Bob Rossi wrote:
>> 
> 
>> > This change essentially adds the command -file-list-exec-source-file to
>> > the mi commands. 
> 
>> 
>> I don't understand why this command is useful.
>> 
>> A UI can get the filename of the currently-executing source file
>> easily enough with "stack-list-frames 0 1".  The pathname is returned
>> as it was recorded in the debug info from the compiler - it might
>> be an absolute path or it might be a relative path.  
> 
> 
> At a minumum, it is a strong convienence function for the front end to
> gdb. It guarentees that the front end is thinking about the same file
> that gdb is. The front end needs to know about absolute paths. It cares
> nothing about relative paths.
> 
> 
>> 
>> If the path is relative, gdb will interpret that pathname based on
>> the directory gdb was invoked--which presumably the UI did itself.
>> Or it will be interpreted relative to any paths added with the
>> "dir" (CLI) / "environment-directory" (MI) command, which the UI
>> would have added as well.  (or it can get the list of paths with
>> the environment-directory command without any arguments)
>> 
>> Why does this information have to be provided by gdb?
> 
> 
> The best answer probably is, because its been provided for the last
> decade ( with annotation 1 and 2 ). I strongly believe that just because
> gdb is switching its interface to front ends, doesn't mean it should
> take away functionality that was provided before.
> 
> However, in my opinion, It doesn't really make sense that each front 
> that implements an interface to gdb figure out how to do each of the 
> steps provided above.  Especially since gdb is already doing all that 
> work.
> 
> Why repeat the functionality in all of the front ends to gdb?
> 
> It would seem that the best solution would be if this command could be
> automatically run ( on the front end's request ) every time the source
> file or line number changed. Just like annotation 1 or 2.

Sounds like the MI interface should provide both (hey if the client 
wants a choice of 14 different salad dressings, then who is gdb to argue).

Someone want to add an extra field, containing that absolute path, to 
the stack-list-frames command?

Andrew