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X11 lint suppression

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Suppress close to 400 warnings generated by gcc on the win/X11/*.c code,
most due to -Wwrite-strings which makes string literals implicitly have
the 'const' attribute.  (Since modifying a string literal results in
undefined behavior, that is an appropriate check to have enabled, but
it can be troublesome since string literals have type 'char *' and code
that uses them that way is correct provided it avoids modifying them.)

 113  warning: initialization discards qualifiers from pointer target type
 127  warning: assignment discards qualifiers from pointer target type
  29  warning: passing argument discards qualifiers from pointer target type
 109  warning: unused parameter
  12  warning: comparison between signed and unsigned

The nhStr() hack casts to 'char *', explicitly removing 'const', for
situations where it isn't feasible to make code directly honor const.
The vast marjority of uses are for the second parameter to XtSetArg(),
which is a macro that actually performs an assignment with the second
argument rather than passing it in a function.  It takes values like
'XtNtop', which doesn't need to be altered (although in many places I
changed that to nhStr(XtNtop) for uniformity with the surrounding code,
and 'XtNbottom', which does need to have the extra const stripping to
avoid a warning.  Go figure.

The nhUse() hack actually uses its argument in a meaningless way if the
code is compiled with FORCE_ARG_USAGE defined.  When GCC_WARN is defined,
FORCE_ARG_USAGE will be enabled if it hasn't been already.  Example:

 /*ARGUSED*/
 int foo(arg)
   int arg;  /* not used */
 {
+  nhUse(arg);
   return 0;
 }

The extra line will expand to ';' when FORCE_ARG_USAGE is not defined
or too
   nhUse_dummy += (unsigned)arg;
when it is.  I figured direct assignment might lead to a different
warning by some compilers in a situation like
   nhUse(arg);
   nhUse(otherarg);
where the first assignment would be clobbered by the second, and using
bitwise operations or safer '+= (arg != 0)' would most likely generate
more non-useful code.  Some tweaking might turn out to be necessary.
This commit is contained in:
PatR
2015-05-06 00:59:15 -07:00
parent e72246f1d1
commit 9de8b03c03
11 changed files with 542 additions and 341 deletions
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win/X11/winval.c
+4 -4
View File
@@ -1,4 +1,4 @@
/* NetHack 3.5 winval.c $NHDT-Date$ $NHDT-Branch$:$NHDT-Revision$ */
/* NetHack 3.5 winval.c $NHDT-Date: 1430899139 2015/05/06 07:58:59 $ $NHDT-Branch: master $:$NHDT-Revision: 1.5 $ */
/* NetHack 3.5 winval.c $Date: 2009/05/06 10:56:06 $ $Revision: 1.4 $ */
/* SCCS Id: @(#)winval.c 3.5 1992/3/7 */
/* Copyright (c) Dean Luick, 1992 */
@@ -45,7 +45,7 @@ create_value(parent, name_value)
num_args = 0;
XtSetArg(args[num_args], XtNborderWidth, 0); num_args++;
XtSetArg(args[num_args], XtNdefaultDistance, 0); num_args++;
XtSetArg(args[num_args], nhStr(XtNdefaultDistance), 0); num_args++;
form = XtCreateManagedWidget(name_value,
formWidgetClass,
parent, args, num_args);
@@ -62,7 +62,7 @@ create_value(parent, name_value)
num_args = 0;
XtSetArg(args[num_args], XtNjustify, XtJustifyRight); num_args++;
XtSetArg(args[num_args], XtNborderWidth, 0); num_args++;
XtSetArg(args[num_args], XtNfromHoriz, name); num_args++;
XtSetArg(args[num_args], nhStr(XtNfromHoriz), name); num_args++;
XtSetArg(args[num_args], XtNinternalHeight, 0); num_args++;
(void) XtCreateManagedWidget(WVALUE,
labelWidgetClass,
@@ -73,7 +73,7 @@ create_value(parent, name_value)
void
set_name(w, new_label)
Widget w;
char *new_label;
const char *new_label;
{
Arg args[1];
Widget name;