fix(builtins): clamp printf precision to prevent panic on large values#1010
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fix(builtins): clamp printf precision to prevent panic on large values#1010
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Closes #1003 — format! panics when precision exceeds u16::MAX (65535). Clamp user-controlled precision to 10000 in FormatSpec::parse to prevent thread panics and associated backtrace information disclosure.
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Summary
FormatSpec::parseformat!u16 limit (65535)What & Why
printf "%.65536f" 1.0caused a thread panic in Rust'sformat!macro, dumping a full stack backtrace to stderr that leaks internal paths and dependency versions. Now precision is clamped to a safe maximum (10000).Tests Added
test_large_precision_no_panic— verifies no panic on precision > 65535test_normal_precision_still_works— verifies normal precision works correctlyCloses #1003