avoid quadratic backtracking in the oracle hint comment pattern - #2495
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manticore-projects merged 1 commit intoAug 22, 2026
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OracleHint checks every comment that precedes a select/insert/update/delete/merge against the block-hint pattern with an unanchored find, so a single line comment that happens to contain a /*+ marker followed by a long run of stars and no closing / makes the greedy match backtrack quadratically (a comment with 100k stars takes around twelve seconds), and this is reachable straight through CCJSqlParserUtil.parse. A hint only ever begins the comment though, so anchoring the pattern at the start of the input lets it reject that line-comment case immediately while still matching every real /+ ... */ hint exactly as before. I have added a regression test that pins the crafted comment under a short preemptive timeout.