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Date: Fri, 27 Aug 2004 13:25:50 +0100
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Subject: [PATCH] zend_operators DVAL_TO_LVAL fix
From: jorton@redhat.com (Joe Orton)

The DVAL_TO_LVAL macro is quite weird, I'm not sure exactly what it's
supposed to be doing but it probably isn't doing it. If the integral
part of d is outside the range of a long, the conversion has undefined
behaviour by the C99 standard; an explicit cast makes no difference
AFAICT.

GCC on IA64 does wierd things with this macro, though I think there's a
GCC bug involved there too.  This fixes the macro to have well-defined
behaviour for all values of 'd', and avoids triggering the GCC bug on
IA64 to boot (both PHP users on that platform will be happy):

Index: Zend/zend_operators.c
===================================================================
RCS file: /repository/ZendEngine2/zend_operators.c,v
retrieving revision 1.194
diff -u -r1.194 zend_operators.c
--- Zend/zend_operators.c	19 Jul 2004 07:19:02 -0000	1.194
+++ Zend/zend_operators.c	27 Aug 2004 12:15:12 -0000
@@ -183,7 +183,15 @@
 	}
 
 
-#define DVAL_TO_LVAL(d, l) (l) = (d) > LONG_MAX ? (unsigned long) (d) : (long) (d)
+#define DVAL_TO_LVAL(d, l) do {			\
+	if ((d) > LONG_MAX) {			\
+		l = LONG_MAX;			\
+	} else if ((d) < LONG_MIN) {		\
+		l = LONG_MIN;			\
+	} else {				\
+		l = (d);			\
+	}					\
+} while (0)
 
 #define zendi_convert_to_long(op, holder, result)					\
 	if (op==result) {												\