fold_binary in fold-const.c in GNU Compiler Collection (gcc) 4.1 improperly handles pointer overflow when folding a certain expr comparison to a corresponding offset comparison in cases other than EQ_EXPR and NE_EXPR, which might introduce buffer overflow vulnerabilities into applications that could be exploited by context-dependent attackers.NOTE: the vendor states that the essence of the issue is "not correctly interpreting an offset to a pointer as a signed value.".