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?RCS: $Id: d_casti32.U,v 3.0 1993/08/18 12:05:47 ram Exp $
?RCS:
?RCS: Copyright (c) 1991-1993, Raphael Manfredi
?RCS: 
?RCS: You may redistribute only under the terms of the Artistic Licence,
?RCS: as specified in the README file that comes with the distribution.
?RCS: You may reuse parts of this distribution only within the terms of
?RCS: that same Artistic Licence; a copy of which may be found at the root
?RCS: of the source tree for dist 3.0.
?RCS:
?RCS: $Log: d_casti32.U,v $
?RCS: Revision 3.0  1993/08/18  12:05:47  ram
?RCS: Baseline for dist 3.0 netwide release.
?RCS:
?X:
?X:	Can the compiler cast large floats to 32-bit integers?
?X:
?MAKE:d_casti32: cat cc ccflags rm intsize Setvar test
?MAKE:	-pick add $@ %<
?S:d_casti32:
?S:	This variable conditionally defines CASTI32, which indicates
?S:	wether the C compiler can cast large floats to 32-bit ints.
?S:.
?T:xxx yyy
?C:CASTI32:
?C:	This symbol is defined if the C compiler can cast negative
?C:	or large floating point numbers to 32-bit ints.
?C:.
?H:#$d_casti32	CASTI32		/**/
?H:.
?LINT:set d_casti32
: check for ability to cast large floats to 32-bit ints.
echo " "
echo 'Checking whether your C compiler can cast large floats to int32.' >&4
if $test "$intsize" -eq 4; then
    xxx=int
else
    xxx=long
fi

$cat >try.c <<EOCP
#include <sys/types.h>
#include <signal.h>
blech() { exit(3); }
main()
{
        $xxx i32;
	double f;
	int result = 0;
	signal(SIGFPE, blech);

	f = (double) 0x7fffffff;
	f = 10 * f;
	i32  = ( $xxx )f;

	if (i32 != ( $xxx )f)
		result |= 1;
	exit(result);
}
EOCP
if $cc -o try $ccflags try.c >/dev/null 2>&1; then
	./try
	yyy=$?
else
	yyy=1
fi
case "$yyy" in
0)	val="$define"
	echo "Yup, it can."
	;;
*)	val="$undef"
	echo "Nope, it can't."
	;;
esac
set d_casti32
eval $setvar
$rm -f try try.*