Ping: [PATCH] libcpp: Improve location for macro names [PR66290]

[Lewis Hyatt <lhyatt@gmail.com>]

Hello-

https://gcc.gnu.org/pipermail/gcc-patches/2022-August/599397.html
May I please ping this patch? Thank you.

-Lewis

On Fri, Aug 5, 2022 at 12:14 PM Lewis Hyatt <lhyatt@gmail.com> wrote:
>
>
> When libcpp reports diagnostics whose locus is a macro name (such as for
> -Wunused-macros), it uses the location in the cpp_macro object that was
> stored by _cpp_new_macro. This is currently set to pfile->directive_line,
> which contains the line number only and no column information. This patch
> changes the stored location to the src_loc for the token defining the macro
> name, which includes the location and range information.
>
> libcpp/ChangeLog:
>
>         PR c++/66290
>         * macro.cc (_cpp_create_definition): Add location argument.
>         * internal.h (_cpp_create_definition): Adjust prototype.
>         * directives.cc (do_define): Pass new location argument to
>         _cpp_create_definition.
>         (do_undef): Stop passing inferior location to cpp_warning_with_line;
>         the default from cpp_warning is better.
>         (cpp_pop_definition): Pass new location argument to
>         _cpp_create_definition.
>         * pch.cc (cpp_read_state): Likewise.
>
> gcc/testsuite/ChangeLog:
>
>         PR c++/66290
>         * c-c++-common/cpp/macro-ranges.c: New test.
>         * c-c++-common/cpp/line-2.c: Adapt to check for column information
>         on macro-related libcpp warnings.
>         * c-c++-common/cpp/line-3.c: Likewise.
>         * c-c++-common/cpp/macro-arg-count-1.c: Likewise.
>         * c-c++-common/cpp/pr58844-1.c: Likewise.
>         * c-c++-common/cpp/pr58844-2.c: Likewise.
>         * c-c++-common/cpp/warning-zero-location.c: Likewise.
>         * c-c++-common/pragma-diag-14.c: Likewise.
>         * c-c++-common/pragma-diag-15.c: Likewise.
>         * g++.dg/modules/macro-2_d.C: Likewise.
>         * g++.dg/modules/macro-4_d.C: Likewise.
>         * g++.dg/modules/macro-4_e.C: Likewise.
>         * g++.dg/spellcheck-macro-ordering.C: Likewise.
>         * gcc.dg/builtin-redefine.c: Likewise.
>         * gcc.dg/cpp/Wunused.c: Likewise.
>         * gcc.dg/cpp/redef2.c: Likewise.
>         * gcc.dg/cpp/redef3.c: Likewise.
>         * gcc.dg/cpp/redef4.c: Likewise.
>         * gcc.dg/cpp/ucnid-11-utf8.c: Likewise.
>         * gcc.dg/cpp/ucnid-11.c: Likewise.
>         * gcc.dg/cpp/undef2.c: Likewise.
>         * gcc.dg/cpp/warn-redefined-2.c: Likewise.
>         * gcc.dg/cpp/warn-redefined.c: Likewise.
>         * gcc.dg/cpp/warn-unused-macros-2.c: Likewise.
>         * gcc.dg/cpp/warn-unused-macros.c: Likewise.
> ---
>
> Notes:
>     Hello-
>
>     The PR (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66290) was originally
>     about the entirely wrong location for -Wunused-macros in C++ mode, which
>     behavior was fixed by r13-1903, but before closing it out I wanted to also
>     address a second point brought up in the PR comments, namely that we do not
>     include column information when emitting diagnostics for macro names, such as
>     is done for -Wunused-macros. The attached patch updates the location stored in
>     the cpp_macro object so that it includes the column and range information for
>     the token comprising the macro name; previously, the location was just the
>     generic one pointing to the whole line.
>
>     The change to libcpp is very small, the reason for all the testsuite changes is
>     that I have updated all tests explicitly looking for the columnless diagnostics
>     (with the "-:" syntax to dg-warning et al) so that they expect a column
>     instead. I also added a new test which verifies the expected range information
>     in diagnostics with carets.
>
>     Bootstrap + regtest on x86-64 Linux looks good. Please let me know if it looks
>     OK? Thanks!
>
>     -Lewis
>
>  libcpp/directives.cc                          |  13 +-
>  libcpp/internal.h                             |   2 +-
>  libcpp/macro.cc                               |  12 +-
>  libcpp/pch.cc                                 |   2 +-
>  gcc/testsuite/c-c++-common/cpp/line-2.c       |   2 +-
>  gcc/testsuite/c-c++-common/cpp/line-3.c       |   2 +-
>  .../c-c++-common/cpp/macro-arg-count-1.c      |   4 +-
>  gcc/testsuite/c-c++-common/cpp/macro-ranges.c |  52 ++
>  gcc/testsuite/c-c++-common/cpp/pr58844-1.c    |   4 +-
>  gcc/testsuite/c-c++-common/cpp/pr58844-2.c    |   4 +-
>  .../c-c++-common/cpp/warning-zero-location.c  |   2 +-
>  gcc/testsuite/c-c++-common/pragma-diag-14.c   |   2 +-
>  gcc/testsuite/c-c++-common/pragma-diag-15.c   |   2 +-
>  gcc/testsuite/g++.dg/modules/macro-2_d.C      |   4 +-
>  gcc/testsuite/g++.dg/modules/macro-4_d.C      |   4 +-
>  gcc/testsuite/g++.dg/modules/macro-4_e.C      |   2 +-
>  .../g++.dg/spellcheck-macro-ordering.C        |   2 +-
>  gcc/testsuite/gcc.dg/builtin-redefine.c       |  18 +-
>  gcc/testsuite/gcc.dg/cpp/Wunused.c            |   6 +-
>  gcc/testsuite/gcc.dg/cpp/redef2.c             |  20 +-
>  gcc/testsuite/gcc.dg/cpp/redef3.c             |  14 +-
>  gcc/testsuite/gcc.dg/cpp/redef4.c             | 520 +++++++++---------
>  gcc/testsuite/gcc.dg/cpp/ucnid-11-utf8.c      |  12 +-
>  gcc/testsuite/gcc.dg/cpp/ucnid-11.c           |  12 +-
>  gcc/testsuite/gcc.dg/cpp/undef2.c             |   6 +-
>  gcc/testsuite/gcc.dg/cpp/warn-redefined-2.c   |  10 +-
>  gcc/testsuite/gcc.dg/cpp/warn-redefined.c     |  10 +-
>  .../gcc.dg/cpp/warn-unused-macros-2.c         |   2 +-
>  gcc/testsuite/gcc.dg/cpp/warn-unused-macros.c |   2 +-
>  29 files changed, 405 insertions(+), 342 deletions(-)
>  create mode 100644 gcc/testsuite/c-c++-common/cpp/macro-ranges.c
>