Dear Dave,
Thanks for sharing all of that! It was very helpful to read it
over again, and it was helpful in IRC yesterday.
As a bit of a "that was strange" moment, I ran the builds again
and did NOT do --disable-bootstrap with the patch on a different
machine. They built and ran fine, with no segfaults during calls to
error(...). I probably forgot to properly clean/build something in my
debugging environment, which caused most of the problems.
I already assigned my Copyright to the FSF, so that part should
be fine! Is there anything else I should be doing?
Sincerely,
JeanHeyd
On Wed, Oct 16, 2019 at 8:51 AM David Malcolm <dmalc...@redhat.com> wrote:
>
> On Tue, 2019-10-15 at 20:31 -0400, JeanHeyd Meneide wrote:
> > Attached is a patch for p1301 that improves in the way Jason Merrill
> > specified earlier
> > (https://gcc.gnu.org/ml/gcc-patches/2019-09/msg00858.html), but it
> > keeps segfaulting on my build of GCC. I don't know what changes I've
> > made that cause it to segfault: it does so whenever the error()
> > function is called but the backtraces aren't showing me anything
> > conclusive.
> >
> > The tests test what I expect them to and the output is fine, I just
> > can't get the segfaults to stop, so I'm putting the patch up so
> > someone can critique what I've written, or someone else to test it
> > too. Sorry for taking so long.
> >
> > Thanks,
> > JeanHeyd
>
> Thanks for posting these patches.
>
> I believe you're a new GCC contributor - welcome!
>
> Having said "welcome", for good or ill, GCC has some legalese that we
> have to follow - to get a patch accepted, see the "Legal Prerequisites"
> section of: https://gcc.gnu.org/contribute.html so you'll need to
> follow that at some point (I hate having to say this).
>
> I got the impression on IRC yesterday that you were having some trouble
> getting your debugging environment set up - it sounded to me like
> you've been "making do" by adding print statements to the parser and
> recompiling each time.
>
> If that's the case, then the best next step is probably to figure out
> how to get you debugging cc1plus using a debugger.
>
> Normally, I run:
> ./xgcc -B.
> and add "-wrapper gdb,--args" to the command line so that the driver
> invokes gdb.
>
> Another way is to invoke gdb and have it directly invoke cc1plus:
> gdb --args ./cc1plus -quiet x.C
>
> In both cases, run it from <your-build-dir>/gcc
>
> See also:
> https://dmalcolm.fedorapeople.org/gcc/newbies-guide/debugging.html
> which has further hints and info on a "nicer" debugging experience.
>
> You mentioned that you normally use gdbserver, which makes me think
> that you're most comfortable using gdb from an IDE. I'm not very
> familiar with gdbserver, but hopefully someone here knows the recipe
> for this that will let you comfortably debug the frontend - without
> needing to add print statements and recompile each time (ugh).
>
> Note that for hacking on the frontend and debugging, I normally
> configure gcc with --disable-bootstrap which saves a *lot* of time;
> similarly I also only build the "gcc" subdirectory and its dependencies
> (I still do a full bootstrap and regression test in a separate
> directory once I've got a candidate patch that I want to test properly
> before submitting to the mailing list).
>
> [I know that you know some/all of this, but I'm posting it here for the
> benefit of people reading the list archives]
>
> Hope this is helpful, and welcome again.
> Dave
>
>
