On Thu, 28 Aug 2025 15:32:58 GMT, Guanqiang Han <g...@openjdk.org> wrote:
>> src/java.base/share/classes/java/lang/Class.java line 4170: >> >>> 4168: // The check utfLen >= nameLen ensures we don't incorrectly >>> return true in case of int overflow. >>> 4169: int utfLen = ModifiedUtf.utfLen(name, 0); >>> 4170: return utfLen <= JAVA_CLASSNAME_MAX_LEN && utfLen >= nameLen; >> >> A typical overflow-conscious idiom is to subtract the unknown value from the >> known positive number and compare with 0. >> Suggestion: >> >> int utfLen = ModifiedUtf.utfLen(name, 0); >> return JAVA_CLASSNAME_MAX_LEN - utfLen >= 0; > > @RogerRiggs Good catch! Fixed. That doesn't seem right to me. If we massively overflow to get a value > -JAVA_CLASSNAME_MAX_LEN but < 0 then the subtraction becomes addition and we get a small positive value. Really ModifiedUtf.utflen should be defined to return long so the caller can more easily deal with overflow. Giant strings are a PITA. ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/26802#discussion_r2309215932
