$ java -version
openjdk version "25.0.4.1" 2026-08-18 LTS
OpenJDK Runtime Environment Temurin-25.0.4.1+1 (build 25.0.4.1+1-LTS)
OpenJDK 64-Bit Server VM Temurin-25.0.4.1+1 (build 25.0.4.1+1-LTS, mixed mode, sharing)

$ unzip -p lib/src.zip java.base/java/util/regex/Pattern.java | sed -n "/Optimize the greedy Loop/,/^        }$/p"
        // Optimize the greedy Loop to prevent exponential backtracking, IF there
        // is no group ref in this pattern. With a non-negative localTCNCount value,
        // the greedy type Loop, Curly will skip the backtracking for any starting
        // position "i" that failed in the past.
        if (!hasGroupRef) {
            for (Node node : topClosureNodes) {
                if (node instanceof Loop) {
                    // non-deterministic-greedy-group
                    ((Loop)node).posIndex = localTCNCount++;
                }
            }
        }

$ grep -ci timeout Pattern.java Matcher.java
Pattern.java: 0
Matcher.java: 0
