Take care of most of include/*.h. I punted on extern.h.
For both src/*.c and include/*.h, I used mismatched checks of
width > 79 to decide which files to look at and then width > 78
to decide which lines to maybe revise, so I didn't look at a bunch
of the files.
I don't plan to go back and do it right. Shortening lines that are
80 or wider to less than 80 is the significant part. Otherwise
emacs puts a backslash in column 80 and the rest of the line of text
on the next line of the screen, making things harder to read.
whitelist the valid cases showing up
If an earlier version of clang is showing more cases (particularly
if they don't make sense), the re-enabling of the warning in
sys/unix/hints/include/compiler.2020 can be made clang-version
specific instead. I had no way to test earlier versions.
option ‘-Wimplicit’ is valid for C/ObjC but not for C++
option ‘-Wimplicit-function-declaration’ is valid for C/ObjC but not for C++
option ‘-Wimplicit-int’ is valid for C/ObjC but not for C++
option ‘-Wmissing-prototypes’ is valid for C/ObjC but not for C++
option ‘-Wmissing-parameter-type’ is valid for C/ObjC but not for C++
option ‘-Wold-style-definition’ is valid for C/ObjC but not for C++
option ‘-Wstrict-prototypes’ is valid for C/ObjC but not for C++
Whitelist all the verified existing triggers:
makedefs.c: In function ‘name_file’
attrib.c: one compiler balks at a ? b : c for fmtstring
cmd.c: In function ‘extcmd_via_menu’
cmd.c: In function ‘wiz_levltyp_legend’
do.c: In function ‘goto_level’
do_name.c: In function ‘coord_desc’
dungeon.c: In function ‘overview_stats’
eat.c: one compiler balks at a ? b : c for fmtstring
end.c: one compiler balks at a ? b : c for fmtstring
engrave.c: In function ‘engr_stats’
hack:c one compiler balks at a ? b : c for fmtstring
hacklib.c: one compiler balks at a ? b : c for fmtstring
insight.c: one compiler balks at a ? b : c for fmtstring
invent.c: In function ‘let_to_name’
light.c: In function ‘light_stats’
mhitm.c: In function ‘missmm’
options.c: In function ‘handler_symset’
options.c: In function ‘basic_menu_colors’
options.c: In function ‘optfn_o_autopickup_exceptions’
options.c: In function ‘optfn_o_menu_colors’
options.c: In function ‘optfn_o_message_types’
options.c: In function ‘optfn_o_status_cond’
options.c: In function ‘optfn_o_status_hilites’
options.c: In function ‘doset’
options.c: In function ‘doset_add_menu’
options.c: In function ‘show_menu_controls’
options.c: In function ‘handle_add_list_remove’
pager.c: In function ‘do_supplemental_info’
pager.c: In function ‘dohelp’
region.c: In function ‘region_stats’
rumors.c: sscanf usage
sounds.c: In function ‘domonnoise’
spell.c: In function ‘dospellmenu’
timeout.c: In function ‘timer_stats’
topten.c: In function ‘outentry’, fscanf, sscanf, fprintf usage
windows.c: In function ‘genl_status_update’
zap.c: one compiler balks at a ? b : c for fmtstring
win/curses/cursstat.c: In function ‘curses_status_update’
win/tty/wintty.c: In function ‘tty_status_update’
win/win32/mswproc.c: In function ‘mswin_status_update’
It turns out that macOS barked when a POP was issued without
a prior PUSH, so since the DISABLE_WARNING_CONDEXPR_IS_CONSTANT
expanded to an empty macro on that platform.
Include a corresponding
RESTORE_WARNING_CONDEXPR_IS_CONSTANT macro for use with that
particular warning.
Microsoft and other non-GNU compilers don't recognize gcc tricks
like /*NOTREACHED*/ to suppress individual warnings. clang recognizes most
of them because it tries to be gcc-compatible. Because of that, a lot of
potentially useful warnings have had to be completely suppressed in the
past in all source files when using the non-gcc compatible compilers.
Now that the code is C99, take advantage of a way to suppress warnings for
individual functions, a big step up from suppressing the warnings
altogether.
Unfortunately, it does require a bit of ugliness caused by the
insertion of some macros in a few spots, but I'm not aware of
a cleaner alternative that still allows warnings to be enabled
in general, while suppressing a warning for known white-listed
instances.
Prior to the warning-tiggering function, place whichever one of
the following is needed to suppress the warning being encountered:
DISABLE_WARNING_UNREACHABLE_CODE
DISABLE_WARNING_CONDEXPR_IS_CONSTANT
After the warning-triggering function, place this:
RESTORE_WARNINGS
Under the hood, the compiler-appropriate warning-disabling
mechanics involve the use of C99 _Pragma, which can be used
in macros.
For unrecognized or inappropriate compilers, or if
DISABLE_WARNING_PRAGMAS is defined, the macros expand
to nothing.