Applied mega patch from Christian Biere to greatly improve feature detection

and make a huge step towards better support for cross-compiling.


git-svn-id: svn://svn.code.sf.net/p/dist/code/trunk/dist@34 2592e710-e01b-42a5-8df0-11608a6cc53d

1 files changed, 11 insertions, 19 deletions

diff --git a/mcon/U/d_sgndchr.U b/mcon/U/d_sgndchr.U
index 08179c9..2f28121 100644
--- a/mcon/U/d_sgndchr.U
+++ b/mcon/U/d_sgndchr.U
@@ -18,7 +18,7 @@
 ?RCS: Revision 3.0  1993/08/18  12:07:16  ram
 ?RCS: Baseline for dist 3.0 netwide release.
 ?RCS:
-?MAKE:d_sgndchr: cat rm +cc +ccflags Setvar
+?MAKE:d_sgndchr: Trylink cat
 ?MAKE:	-pick add $@ %<
 ?S:d_sgndchr:
 ?S:	This variable conditionally defines the SIGNEDCHAR symbol, which
@@ -31,29 +31,21 @@
 ?C:.
 ?H:#$d_sgndchr SIGNEDCHAR	/**/
 ?H:.
-?F:!try
 ?LINT:set d_sgndchr
 : check for signed chars
 echo " "
 echo "Checking to see if your C compiler can do signed chars..." >&4
-$cat >try.c <<'EOCP'
-int main()
+$cat >try.c <<EOC
+int main(void)
 {
-	char c = 0;
-
-	c--;
-	exit(c >= 0);
+	switch (1) {
+	case 0:
+	case ((char) -1 < 0):
+		break;
+	}
+	return 0;
 }
-EOCP
-$cc $ccflags -o try try.c
-if ./try; then
-	val="$define"
-	echo "It certainly can."
-else
-	val="$undef"
-	echo "It can't.  I'll have to make some things type short."
-fi
+EOC
 set d_sgndchr
-eval $setvar
-$rm -f try*
+eval $trylink