Re: [PATCH] libstdc++: fix pointer type exception catch [PR105387]

[Jonathan Wakely <jwakely.gcc@gmail.com>]

On Wed, 4 May 2022 at 12:14, Jonathan Wakely wrote:
>
> On Tue, 3 May 2022 at 11:57, Jakob Hasse via Libstdc++
> <libstdc++@gcc.gnu.org> wrote:
> >
> > This is a patch for the bug 105387 reported in bugzilla: 105387 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105387. This report should contain all the necessary information about the issue. But the patch there was just a preliminary one.
> > I created a proper patch with the fix and a test case, based on TAG releases/gcc-11.2.0 (7ca388565af176bd4efd4f8db1e5e9e11e98ef45). The changelog is part of the commit message in the patch.
>
> Thanks for the patch!
>
> Some boring administrative comments:
>
> In the summary line of the git commit message:
> - The component should be libstdc++ not libstdc++-v3.
> - The PR number should include "PR" i.e. [PR105387].
> Your email Subject: gets this right, but the patch doesn't.
> This is (not very well) documented at
> https://gcc.gnu.org/contribute.html#patches

Oh, and libstdc++ patches need to be CC'd to both the libstdc++ list
*and* the gcc-patches list, as per
https://gcc.gnu.org/lists.html


>
> Your new testcase has a FSF copyright notice. Unless you have already
> completed the paperwork to assign your work (either for just this
> change, or this and all future changes) to the FSF then you need to
> either do that legal paperwork, or alternatively contribute under the
> DCO terms without assigning copyright. See
> https://gcc.gnu.org/contribute.html#legal
> For simplicity and to expedite the process, I suggest just removing
> the copyright notice and license notice from the testcase, and adding
> a Signed-off-by: tag to the commit message, as per
> https://gcc.gnu.org/dco.html
>
> As for the actual code ...
>
> The testcase has unused parameters for the 'main' function:
> +int main(int argc, char **argv)
> That should be just 'int main()' because the parameters aren't used.
>
> The testcase should mention the PR, e.g.
> // PR libstdc++/105387
>
> I'd prefer if the test contains the original reproducer from the PR,
> which doesn't rely on internal details like __pointer_type_info. You
> can put the portable test from the PR into one function and the
> non-portable test into another function, and call them both from
> main().
>
> I'd prefer using unsigned char for the buffer, rather than uint8_t
> (which requires the <stdint.h> header, and might be a typedef for
> 'int' on 8-bit targets, rather than a character type).
>
> The test uses nullptr which is not available in C++98. It should
> either require c++11 so it's UNSUPPORTED for c++98 mode:
> // { dg-do run { target c++11 } }
> or just use 0 instead of nullptr.
>
>
>
> > Number of unexpected failures went down by one and the number of unsupported tests went  up by one. 17_intro/headers/c++1998/49745.cc suddenly passes, 22_locale/time_get/get_date/wchar_t/4.cc is suddenly unsupported. I don't know why.
>
> I don't understand that either. I'll try to reproduce that.