fix: compile the float overflow-widening ladder eagerly (trim compatibility) - #207
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…bility) Remove Base.inferencebarrier from the four widened recursive calls in floats.jl (_parsedigits/_parsefrac/_parseexp). The ladder is bounded in type space (UInt64 -> UInt128 -> BigInt, overflows(BigInt) == false ends the recursion) and the @noinline wrappers already keep each step compiling separately, so base-case compilation stays contained. The barrier made the widened continuation reachable only through runtime dispatch. Under the JIT that's just a lazy-compile; in a statically compiled binary (juliac --trim) the widened instance doesn't exist, so parsing a wide-digit float would fail at runtime — and the four dynamic sites are verifier errors that block trim builds of anything using Parsers' float path. Measured: precompile does not regress (compilecache 5.3s -> 3.8s on this machine vs the release lineage); full suite green (566038 tests); all ladder rungs verified correct (20+, 40+ digit mantissas, wide exponents, BigFloat).
Compiles test/parsers_trim_workload.jl with juliac --trim=safe (JuliaC.jl, error budget zero) and runs the executable, so the overflow-widening ladder fix can't silently regress — under the old Base.inferencebarrier form these were verifier errors AND the widened instances were missing from trimmed binaries (wide-mantissa parses would fail at runtime). The workload asserts bit-exact rounding through every ladder rung (UInt64 → UInt128 → BigInt mantissas, fractional and exponent variants), float edge cases (Inf overflow, denormals, floatmax, NaN), Float16/32/64, ints, and tryparse. Skips on Julia < 1.12 and on prerelease builds.
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Jul 14, 2026
Compiles test/json_trim_workload.jl with juliac --trim=safe (JuliaC.jl, error budget zero) and runs the executable, so the trim-verifier fixes in this PR can't silently regress. Same harness shape as StructUtils/HTTP. The workload asserts runtime values across typed parse (@defaults incl. defaulted fields, Vector/Dict targets), the rewritten error paths (the unknown-field message with its PtrString key formatting, and the bad unknown_fields-option message — both triggered and matched at runtime), untyped parse with the isa-narrowing pattern trim-compiled consumers need, JSON writing incl. escapes and struct roundtrips, and the hand-formatted Date/DateTime/Time lowers (exact renderings incl. millisecond padding). The trim env temporarily pins Parsers#trim-verifier-fixes: JSON's number parsing pulls Parsers' float path into the verify set, and the registered release fails verification until JuliaData/Parsers.jl#207 ships (TODO in the setup script). Skips on Julia < 1.12 and on prerelease builds.
Skip JuliaC trim compilation on 32-bit hosts that lack a compatible C toolchain. Constrain the ARFFFiles downstream job to OrderedCollections 1 until ARFFFiles stops constructing ordered tables from unordered Dict inputs.
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Removes
Base.inferencebarrierfrom the four widened recursive calls infloats.jl(_parsedigits/_parsefrac/_parseexpcontinuations).Why
The barrier makes the widened continuation reachable only through runtime dispatch. Under the JIT that's a lazy compile; in a statically compiled binary (
juliac --trim) the widened instance doesn't exist, so parsing a wide-digit float would fail at runtime — and the four dynamic sites are verifier errors that block trim builds of anything using Parsers' float path (e.g. JSON number parsing).Why it's safe
UInt64 → UInt128 → BigInt, andoverflows(BigInt) == falseends the recursion — so eager inference terminates with at most three ladder instances per concrete (conf, source, continuation) combination.@noinline_parsedigits/_parsefrac/_parseexpwrappers (which exist precisely to contain base-case compilation) still keep each ladder step compiling separately.Measurements
Base.compilecache(Parsers)5.3s → 3.8s on the same machine vs the release lineage.BigFloattargets.juliac --trim=safewith zero verifier errors and the binary runs.🤖 Generated with Claude Code
Co-authored by Codex