diff --git a/Zend/tests/bug39018.phpt b/Zend/tests/bug39018.phpt
index 32566ba8646..a00e1fb819d 100644
--- a/Zend/tests/bug39018.phpt
+++ b/Zend/tests/bug39018.phpt
@@ -64,6 +64,8 @@ print "\nDone\n";
 --EXPECTF--
 Notice: String offset cast occurred in %s on line %d
 
+Notice: Uninitialized string offset: %s in %s on line 6
+
 Notice: Uninitialized string offset: 0 in %s on line %d
 
 Notice: Uninitialized string offset: 0 in %s on line %d
diff --git a/Zend/tests/dval_to_lval_32.phpt b/Zend/tests/dval_to_lval_32.phpt
new file mode 100644
index 00000000000..f2acc39f51f
--- /dev/null
+++ b/Zend/tests/dval_to_lval_32.phpt
@@ -0,0 +1,32 @@
+--TEST--
+zend_dval_to_lval preserves low bits  (32 bit long)
+--SKIPIF--
+<?php
+if (PHP_INT_SIZE != 4)
+	 die("skip for machines with 32-bit longs");
+?>
+--FILE--
+<?php
+	/* test doubles around -4e21 */
+	$values = [
+		-4000000000000001048576.,
+		-4000000000000000524288.,
+		-4000000000000000000000.,
+		-3999999999999999475712.,
+		-3999999999999998951424.,
+	];
+	/* see if we're rounding negative numbers right */
+	$values[] = -2147483649.8;
+
+	foreach ($values as $v) {
+		var_dump((int)$v);
+	}
+
+?>
+--EXPECT--
+int(-2056257536)
+int(-2055733248)
+int(-2055208960)
+int(-2054684672)
+int(-2054160384)
+int(2147483647)
diff --git a/Zend/tests/dval_to_lval_64.phpt b/Zend/tests/dval_to_lval_64.phpt
new file mode 100644
index 00000000000..da7f56d81ce
--- /dev/null
+++ b/Zend/tests/dval_to_lval_64.phpt
@@ -0,0 +1,29 @@
+--TEST--
+zend_dval_to_lval preserves low bits  (64 bit long)
+--SKIPIF--
+<?php
+if (PHP_INT_SIZE != 8)
+	 die("skip for machines with 64-bit longs");
+?>
+--FILE--
+<?php
+	/* test doubles around -4e21 */
+	$values = [
+		-4000000000000001048576.,
+		-4000000000000000524288.,
+		-4000000000000000000000.,
+		-3999999999999999475712.,
+		-3999999999999998951424.,
+	];
+
+	foreach ($values as $v) {
+		var_dump((int)$v);
+	}
+
+?>
+--EXPECT--
+int(2943463994971652096)
+int(2943463994972176384)
+int(2943463994972700672)
+int(2943463994973224960)
+int(2943463994973749248)
diff --git a/Zend/zend_operators.h b/Zend/zend_operators.h
index 93c60e49015..a82c14b8c26 100644
--- a/Zend/zend_operators.h
+++ b/Zend/zend_operators.h
@@ -68,22 +68,40 @@ END_EXTERN_C()
 
 #if ZEND_DVAL_TO_LVAL_CAST_OK
 # define zend_dval_to_lval(d) ((long) (d))
-#elif SIZEOF_LONG == 4 && defined(HAVE_ZEND_LONG64)
+#elif SIZEOF_LONG == 4
 static zend_always_inline long zend_dval_to_lval(double d)
 {
 	if (d > LONG_MAX || d < LONG_MIN) {
-		return (long)(unsigned long)(zend_long64) d;
+		double	two_pow_32 = pow(2., 32.),
+				dmod;
+
+		dmod = fmod(d, two_pow_32);
+		if (dmod < 0) {
+			/* we're going to make this number positive; call ceil()
+			 * to simulate rounding towards 0 of the negative number */
+			dmod = ceil(dmod) + two_pow_32;
+		}
+		return (long)(unsigned long)dmod;
 	}
-	return (long) d;
+	return (long)d;
 }
 #else
 static zend_always_inline long zend_dval_to_lval(double d)
 {
 	/* >= as (double)LONG_MAX is outside signed range */
-	if (d >= LONG_MAX) {
-		return (long)(unsigned long) d;
+	if (d >= LONG_MAX || d < LONG_MIN) {
+		double	two_pow_64 = pow(2., 64.),
+				dmod;
+
+		dmod = fmod(d, two_pow_64);
+		if (dmod < 0) {
+			/* no need to call ceil; original double must have had no
+			 * fractional part, hence dmod does not have one either */
+			dmod += two_pow_64;
+		}
+		return (long)(unsigned long)dmod;
 	}
-	return (long) d;
+	return (long)d;
 }
 #endif
 /* }}} */