llama.cpp

e397d388 - common/json-schema: fix: handle non-capturing groups (?:...) in JSON schema pattern converter (#21124)

common/json-schema: fix: handle non-capturing groups (?:...) in JSON schema pattern converter (#21124) The regex-to-grammar converter in _visit_pattern() crashes with SIGSEGV when a JSON schema "pattern" field contains a non-capturing group (?:...). Root cause: when the parser sees '(' followed by '?', it pushes a warning but does not advance past '?:'. The recursive transform() call then interprets '?' as a quantifier and calls seq.back() on an empty vector, causing undefined behavior. This commonly occurs when serving OpenAI-compatible tool calls from clients that include complex regex patterns in their JSON schemas (e.g., date validation patterns like ^(?:(?:\d\d[2468][048]|...)-02-29|...)$). The fix: - Skip '?:' after '(' to treat non-capturing groups as regular groups - For unsupported syntax (?=, ?!, etc.), skip to matching ')' safely, handling escaped characters to avoid miscounting parenthesis depth - Adjust the ')' unbalanced-parentheses check using direct char comparisons instead of substr - Add test cases for non-capturing groups (C++ only, as the JS/Python implementations do not yet support this syntax)