Thanks for all the replies, both on the list and off. The problem actually ended up being a lack of virtual destructor in our String class. Not sure how it worked before... maybe it always had this problem but the Intel libraries didn't catch the invalid free in the same way. Not sure. Thanks again, -Tom -- View this message in context: http://www.nabble.com/Problem-going-to-GCC-from-ICC-tp15743483p15768977.html Sent from the gcc - Help mailing list archive at Nabble.com.