1 ?RCS: $Id: d_castneg.U 1 2006-08-24 12:32:52Z rmanfredi $
3 ?RCS: Copyright (c) 1991-1997, 2004-2006, Raphael Manfredi
5 ?RCS: You may redistribute only under the terms of the Artistic Licence,
6 ?RCS: as specified in the README file that comes with the distribution.
7 ?RCS: You may reuse parts of this distribution only within the terms of
8 ?RCS: that same Artistic Licence; a copy of which may be found at the root
9 ?RCS: of the source tree for dist 4.0.
11 ?RCS: $Log: d_castneg.U,v $
12 ?RCS: Revision 3.0.1.2 1995/05/12 12:11:21 ram
13 ?RCS: patch54: made sure cc and ccflags are conditional dependencies
14 ?RCS: patch54: added improved test case for Interactive Unix
16 ?RCS: Revision 3.0.1.1 1994/10/29 16:10:50 ram
17 ?RCS: patch36: don't forget to tell user about compilation failures (ADO)
18 ?RCS: patch36: declare signal handler correctly using 'signal_t' (ADO)
20 ?RCS: Revision 3.0 1993/08/18 12:05:47 ram
21 ?RCS: Baseline for dist 3.0 netwide release.
24 ?X: Can the compiler cast negative / odd floats to unsigned values.
26 ?MAKE:d_castneg castflags: cat +cc +ccflags rm Setvar signal_t
27 ?MAKE: -pick add $@ %<
29 ?S: This variable conditionally defines CASTNEG, which indicates
30 ?S: wether the C compiler can cast negative float to unsigned.
33 ?S: This variable contains a flag that precise difficulties the
34 ?S: compiler has casting odd floating values to unsigned long:
36 ?S: 1 = couldn't cast < 0
37 ?S: 2 = couldn't cast >= 0x80000000
38 ?S: 4 = couldn't cast in argument expression list
41 ?C: This symbol is defined if the C compiler can cast negative
42 ?C: numbers to unsigned longs, ints and shorts.
45 ?C: This symbol contains flags that say what difficulties the compiler
46 ?C: has casting odd floating values to unsigned long:
48 ?C: 1 = couldn't cast < 0
49 ?C: 2 = couldn't cast >= 0x80000000
50 ?C: 4 = couldn't cast in argument expression list
52 ?H:#$d_castneg CASTNEGFLOAT /**/
53 ?H:#define CASTFLAGS $castflags /**/
57 : check for ability to cast negative floats to unsigned
59 echo 'Checking whether your C compiler can cast negative float to unsigned.' >&4
61 #include <sys/types.h>
63 $signal_t blech() { exit(7); }
64 $signal_t blech_in_list() { exit(4); }
65 unsigned long dummy_long(p) unsigned long p; { return p; }
66 unsigned int dummy_int(p) unsigned int p; { return p; }
67 unsigned short dummy_short(p) unsigned short p; { return p; }
73 unsigned short ashort;
76 signal(SIGFPE, blech);
77 along = (unsigned long)f;
78 aint = (unsigned int)f;
79 ashort = (unsigned short)f;
80 if (along != (unsigned long)-123)
82 if (aint != (unsigned int)-123)
84 if (ashort != (unsigned short)-123)
86 f = (double)0x40000000;
89 along = (unsigned long)f;
90 if (along != 0x80000000)
94 along = (unsigned long)f;
95 if (along != 0x7fffffff)
99 along = (unsigned long)f;
100 if (along != 0x80000001)
105 ?X: The following is a test for Interactive Unix Version 4.1, which
106 ?X: has an 'improved' compiler which can correctly cast negative
107 ?X: floats in expression lists, but apparently not in argument lists.
108 ?X: Contributed by Winfried Koenig <win@incom.rhein-main.de>
110 signal(SIGFPE, blech_in_list);
112 along = dummy_long((unsigned long)f);
113 aint = dummy_int((unsigned int)f);
114 ashort = dummy_short((unsigned short)f);
115 if (along != (unsigned long)123)
117 if (aint != (unsigned int)123)
119 if (ashort != (unsigned short)123)
125 if $cc $ccflags -o try try.c >/dev/null 2>&1; then
129 echo "(I can't seem to compile the test program--assuming it can't)"
137 echo "Nope, it can't."