[Bug web/82798] New: Inconsistent descriptions for warning options in documentation

julien at trigofacile dot com gcc-bugzilla@gcc.gnu.org
Wed Nov 1 22:20:00 GMT 2017


https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82798

            Bug ID: 82798
           Summary: Inconsistent descriptions for warning options in
                    documentation
           Product: gcc
           Version: 7.2.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: web
          Assignee: unassigned at gcc dot gnu.org
          Reporter: julien at trigofacile dot com
  Target Milestone: ---

In GCC 7 documentation:

1/ One can read "Some options, such as -Wall and -Wextra, turn on other
options, such as -Wunused" and later in the description of -Wunused:  "note
that -Wall implies -Wunused".

However, "-Wunused" is not listed in the list of warning flags turned on by
-Wall.
4 warning flags are instead listed in the -Wall list: -Wunused-function,
-Wunused-label, -Wunused-value and -Wunused-variable.
And 2 warning flags are listed in the -Werror list: -Wunused-parameter,
-Wunused-but-set-parameter.

It seems a bit confusing, and I believe there is something to fix.
Maybe in fact -Wunused is not turned on by -Wall?


2/ -Wuninitialized is listed in both -Wall and -Werror list.
And the description of -Wuninitialized does not mention either of them.
I believe there is something to fix for that.


3/ -Wall should list "-Walloc-size-larger-than=PTRDIFF_MAX" in the warning
flags turned on (according to GCC 7 changes).  The description should mention
that at the same time.


4/ The description of -Wexpansion-to-defined mentions that it is enabled by
-Wextra and -Wpedantic.  The list of warning flags turned on by them should
mention that.


5/ -Wall mentions two warnings that are not described in the documentation:
-Wmultistatement-macros and -Wreorder.  Can they be described please?


Thanks beforehand for fixing these issues.

Julien ÉLIE


More information about the Gcc-bugs mailing list