[vpnc-devel] uninitialised variables in vpnc.c

[Jukka Salmi]

Hello,

(Joerg, thanks for your nightly commits!)

while building vpnc.c there are some warnings:

[...]
vpnc.c: In function 'lifetime_ipsec_process':
vpnc.c:1173: warning: 'value' may be used uninitialized in this function
vpnc.c: In function 'lifetime_ike_process':
vpnc.c:1146: warning: 'value' may be used uninitialized in this function
[...]

The code fragments causing these warnings are

	uint32_t value;
	[...]
	if (...)
		value = ...;
	else if (...)
		value = ...;
	else
		assert(0);
	[...]
	(use value)
	[...]

This obviously becomes a problem as soon as NDEBUG is defined.

So, how should this be fixed?  By initialising value?  By explicitly
calling abort(3) after assert(0)?  Or by ignoring the warnings and
adding a comment to the README telling that NDEBUG should never be
defined? ;-)


Regards, Jukka

-- 
This email fills a much-needed gap in the archives.
-------------- next part --------------
Index: vpnc.c
===================================================================
--- vpnc.c	(revision 421)
+++ vpnc.c	(working copy)
@@ -1143,7 +1143,7 @@
 
 static void lifetime_ike_process(struct sa_block *s, struct isakmp_attribute *a)
 {
-	uint32_t value;
+	uint32_t value = 0;
 
 	assert(a != NULL);
 	assert(a->type == IKE_ATTRIB_LIFE_TYPE);
@@ -1170,7 +1170,7 @@
 
 static void lifetime_ipsec_process(struct sa_block *s, struct isakmp_attribute *a)
 {
-	uint32_t value;
+	uint32_t value = 0;
 
 	assert(a != NULL);
 	assert(a->type == ISAKMP_IPSEC_ATTRIB_SA_LIFE_TYPE);
-------------- next part --------------
Index: vpnc.c
===================================================================
--- vpnc.c	(revision 421)
+++ vpnc.c	(working copy)
@@ -1156,8 +1156,10 @@
 		value = a->next->u.attr_16;
 	else if (a->next->af == isakmp_attr_lots && a->next->u.lots.length == 4)
 		value = ntohl(*((uint32_t *) a->next->u.lots.data));
-	else
+	else {
 		assert(0);
+		abort();
+	}
 
 	DEBUG(2, printf("got ike lifetime attributes: %d %s\n", value,
 		(a->u.attr_16 == IKE_LIFE_TYPE_SECONDS) ? "seconds" : "kilobyte"));
@@ -1183,8 +1185,10 @@
 		value = a->next->u.attr_16;
 	else if (a->next->af == isakmp_attr_lots && a->next->u.lots.length == 4)
 		value = ntohl(*((uint32_t *) a->next->u.lots.data));
-	else
+	else {
 		assert(0);
+		abort();
+	}
 
 	DEBUG(2, printf("got ipsec lifetime attributes: %d %s\n", value,
 		(a->u.attr_16 == IPSEC_LIFE_SECONDS) ? "seconds" : "kilobyte"));