Re: [PATCH 0/2] Better handling of slow remote transfers

Gary Benson
2015-08-12T10:38:35Z

Pedro Alves wrote:
> On 08/12/2015 10:48 AM, Gary Benson wrote:
> > Joel Brobecker wrote:
> > > > At any rate, I think the default behaviour for 7.10 has to be
> > > > the default behaviour of 7.9 (given that, for example, we're
> > > > not going to make file transfer more adequately interruptible
> > > > for 7.10).
> > >
> > > That makes sense to me.
> >
> > If we are to reset the default sysroot to "" then please
> > consider the series I posted that added the auto-target-prefix
> > functionality:
> >
> > https://sourceware.org/ml/gdb-patches/2015-07/msg00828.html
>
> I'd really prefer not adding magic at the last minute to the 7.10
> release. That would leave no breathing space to sort out further
> design mistakes, which I'm sure we'll trip on.

The only real "magic" that series adds is this:

+ if (target_filesystem_is_local ())
...
+ else if (auto_target_prefix && *gdb_sysroot == '\0')
+ {
+ /* Set the absolute prefix to "target:" for executable files
+ and for shared libraries whose executable filename has a
+ "target:"-prefix. */
+ if (!is_solib
+ || (exec_filename != NULL
+ && is_target_filename (exec_filename)))
+ {
+ sysroot = xstrdup (TARGET_FILENAME_PREFIX);
+ make_cleanup (xfree, sysroot);
+ }
+ }

*If* it proves to be a problem then we can deprecate the set/show
auto-target-prefix boolean.

It seems like you're saying this series is a big change, but it's
really not: the core of it is that little snippet of logic, which
is easy enough to reason about:

IF target filesystem is remote
AND auto_target_prefix is enabled
AND no sysroot is set
AND (we're looking for an executable
OR we're looking for a solib loaded by a target-prefixed executable):
Prefix the filename with "target:"

It's certainly way less invasive a change than making transfers
interruptible would be.

> I think we need to unblock 7.10 as soon as possible so that 7.11
> with all the neat sysroot features happens sooner too. :-)

Sure, but why not unblock it this way so that 7.10 users can have
the neat sysroot features, *if and only if* they use GDB in a way
that didn't make sense in 7.9?

Thanks,
Gary

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