[krbdev.mit.edu #8151] Build errors on OpenWrt/GCC 4.8

["W.Michael Petullo" via RT]

I am trying to build krb5-1.13.1 for OpenWrt using GCC 4.8. The build
process fails with a number of errors. For example:

	cc_file.c:396:5: error: 'maxsize' may be used uninitialized in this function [-Werror=maybe-uninitialized]
	     return load_data(context, id, maxsize, buf);
	     ^
	cc_file.c:1091:12: note: 'maxsize' was declared here
	     size_t maxsize;
		    ^
	cc_file.c: In function 'read_principal':
	cc_file.c:414:9: error: 'maxsize' may be used uninitialized in this function [-Werror=maybe-uninitialized]
	     ret = load_principal(context, id, maxsize, &buf);
		 ^
	cc1: some warnings being treated as errors
	Makefile:779: recipe for target 'cc_file.so' failed
	make[7]: *** [cc_file.so] Error 1
	make[7]: Leaving directory '/home/mike/Source/openwrt/openwrt/build_dir/target-mips_34kc_uClibc-0.9.33.2/krb5-1.13.1/src/lib/krb5/ccache'

and later:

	pkinit_crypto_openssl.c: In function 'pkinit_open_session':
	pkinit_crypto_openssl.c:3650:9: warning: assuming pointer wraparound does not occur when comparing P +- C1 with P +- C2 [-Wstrict-overflow]
		 for (cp = tinfo.label + sizeof(tinfo.label); cp > tinfo.label; cp--) {
		 ^
	pkinit_crypto_openssl.c:3650:9: warning: assuming pointer wraparound does not occur when comparing P +- C1 with P +- C2 [-Wstrict-overflow]
	pkinit_crypto_openssl.c:3650:9: warning: assuming pointer wraparound does not occur when comparing P +- C1 with P +- C2 [-Wstrict-overflow]
	pkinit_crypto_openssl.c:3650:9: warning: assuming pointer wraparound does not occur when comparing P +- C1 with P +- C2 [-Wstrict-overflow]
	pkinit_crypto_openssl.c:3684:29: error: 'label_len' may be used uninitialized in this function [-Werror=maybe-uninitialized]
			 if (asprintf(&p11name,
				     ^
	cc1: some warnings being treated as errors
	Makefile:804: recipe for target 'pkinit_crypto_openssl.so' failed
	make[5]: *** [pkinit_crypto_openssl.so] Error 1
	make[5]: Leaving directory '/home/mike/Source/openwrt/openwrt/build_dir/target-mips_34kc_uClibc-0.9.33.2/krb5-1.13.1/src/plugins/preauth/pkinit'

I am not suggesting that the following is the proper fix, but it does
illustrate where the problem seems to lie. krb5-1.13.1 builds with the
following patch applied:

	diff -u --recursive krb5-1.13.1-vanilla/src/lib/krad/packet.c krb5-1.13.1/src/lib/krad/packet.c
	--- krb5-1.13.1-vanilla/src/lib/krad/packet.c   2015-02-22 10:08:38.213087138 -0500
	+++ krb5-1.13.1/src/lib/krad/packet.c   2015-02-22 10:13:25.223709951 -0500
	@@ -253,7 +253,7 @@
	 {
	     krb5_error_code retval;
	     krad_packet *pkt;
	-    uchar id;
	+    uchar id = 0;
	     size_t attrset_len;

	     pkt = packet_new();
	diff -u --recursive krb5-1.13.1-vanilla/src/lib/krb5/ccache/cc_file.c krb5-1.13.1/src/lib/krb5/ccache/cc_file.c
	--- krb5-1.13.1-vanilla/src/lib/krb5/ccache/cc_file.c   2015-02-22 10:08:38.211087133 -0500
	+++ krb5-1.13.1/src/lib/krb5/ccache/cc_file.c   2015-02-22 10:14:15.410819464 -0500
	@@ -401,7 +401,7 @@
	 {
	     krb5_error_code ret;
	     struct k5buf buf;
	-    size_t maxsize;
	+    size_t maxsize = 0;

	     *princ = NULL;
	     k5_cc_mutex_assert_locked(context, &((fcc_data *)id->data)->lock);
	@@ -1088,7 +1088,7 @@
	     krb5_fcc_cursor *fcursor = *cursor;
	     fcc_data *data = id->data;
	     struct k5buf buf;
	-    size_t maxsize;
	+    size_t maxsize = 0;

	     memset(creds, 0, sizeof(*creds));
	     k5_cc_mutex_lock(context, &data->lock);
	diff -u --recursive krb5-1.13.1-vanilla/src/plugins/preauth/pkinit/pkinit_crypto_openssl.c krb5-1.13.1/src/plugins/preauth/pkinit/pkinit_crypto_openssl.c
	--- krb5-1.13.1-vanilla/src/plugins/preauth/pkinit/pkinit_crypto_openssl.c      2015-02-22 10:08:38.190087088 -0500
	+++ krb5-1.13.1/src/plugins/preauth/pkinit/pkinit_crypto_openssl.c      2015-02-22 10:17:37.981263250 -0500
	@@ -3593,7 +3593,7 @@
	 {
	     CK_ULONG i, r;
	     unsigned char *cp;
	-    size_t label_len;
	+    size_t label_len = 0;
	     CK_ULONG count = 0;
	     CK_SLOT_ID_PTR slotlist;
	     CK_TOKEN_INFO tinfo;

-- 
Mike

:wq