Re: [PATCH 4/5] Use TARGET_FILENAME_PREFIX as the system root in some cases

[Sandra Loosemore <sandra@codesourcery.com>]

On 07/28/2015 11:35 AM, Doug Evans wrote:
>
> One thing that comes to mind is that there's no indication/warning
> here of the potential massive responsiveness hit people may take
> if they turn this feature on, plus an explanation of what's going
> on, or how they can do things differently to avoid it.

Yes.  The delay would be more tolerable if users were given some clue 
what GDB is doing.

> If, after doing:
>
> (gdb) target remote :9999
>
> the user was first prompted with something like:
>
> "Warning: I have no way to find files with debug info locally,
> and auto-target-prefix is set to "on",
> so I will try to fetch these files from the target.
> This may take time.  If you want to avoid having me try to transfer
> files from the target, you can do the following:
> blah blah blah
> Are you sure you want to continue?"
> [suitably cleaned up, I didn't want to spend any time wordsmithing that]
>
> then that may be sufficient.  What do others think?

The problem with forcing the user to answer question here is that it'll 
screw up a lot of GDB startup scripts.  Maybe stuff like launching GDB 
from Eclipse, too.

My preference would be to make GDB give a message when transferring 
files from the target, like

Reading /full/path/to/libc-2.21.so (12236020 bytes) from target.
Use "set sysroot" to set a local pathname for this file instead.

and make the read operation interruptible so that if it's taking too 
long, the user can stop the transfer and do the "set sysroot" thing as 
suggested.

-Sandra