grammar: fix regression caused by #17381 #17412
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pwilkin
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Nov 20, 2025
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Yeah, my bad, should've used a system-independent data type to begin with (but see comment on condition).
src/llama-grammar.cpp
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| throw std::runtime_error(std::string("expecting ',' at ") + pos); | ||
| } | ||
| if (min_times > MAX_REPETITION_THRESHOLD || (max_times != UINT64_MAX && max_times > MAX_REPETITION_THRESHOLD)) { | ||
| if (min_times > MAX_REPETITION_THRESHOLD || max_times > MAX_REPETITION_THRESHOLD) { |
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This is going to be wrong. The condition was "if min_times exceeds threshold or (max_times is defined and exceeds threshold)". Now, this is going to trigger if max_times is not defined (so with X{n,} patterns)
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If we're not going to use std::optional like I wanted in the first approach, then I think this is the only way to do it. This is bascially equivalent to checking for == -1 or, as the original test had it, < 0.
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hmm ok I thought one of the condition was overlapping the other.
using uint_max as a special value is fine, the main advantage of std::optional is its readability which is easy to replicate: c0b9903
pwilkin
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Nov 20, 2025
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LGTM now. |
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(I can't merge BTW so you'll have to get someone with write access to approve a review) |
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For extra safe, I'll merge when the windows CI on my fork passes (skipping long waiting line on the main repo) |
ggerganov
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Nov 20, 2025
SamuelOliveirads
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Dec 29, 2025
* grammar : fix JSON Schema for string regex with top-level alt. (ggml-org#9903) Prior to this commit, using a JSON Schema containing a string with `pattern` regular expression that uses top-level alternation (e.g. `"pattern": "^A|B|C|D$"`) would result in invalid JSON output from the constrained sampling grammar, because it ended up creating a grammar rule like this for the string: ``` thing ::= "\"" "A" | "B" | "C" | "D" "\"" space ``` Note that this rule will only match a starting quote for the "A" case, and will only match an ending quote for the "D" case, so this rule will always produce invalid JSON when used for sampling (that is, the JSON will always be lacking the starting quote, the ending quote, or both). This was fixed in a simple way by adding parentheses to the generated rule (for all string pattern rules, to keep it simple), such that the new generated rule looks like this (correct): ``` thing ::= "\"" ("A" | "B" | "C" | "D") "\"" space ``` * grammars : add English-only grammar (ggml-org#10612) * grammar : handle maxItems == 0 in JSON schema (ggml-org#13117) Co-authored-by: Richard Lyons <frob@cloudstaff.com> * grammar-parser : fix possible null-deref (ggml-org#9004) Fixes: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=70680 Signed-off-by: David Korczynski <david@adalogics.com> * llama : fix typo in llama-grammar.h [no ci] (ggml-org#11816) * * server: fix "--grammar-file" parameter (ggml-org#12285) * common : use std::string_view now that we target c++17 (ggml-org#14319) * json : support `enum` values within `allOf` (ggml-org#15830) * grammar : use int64_t to avoid int overflows in int schema to grammar conversion logic (ggml-org#16626) * grammar : support array references in json schema (ggml-org#16792) * grammar : support array references in json schema * Update json-schema-to-grammar.cpp Co-authored-by: Sigbjørn Skjæret <sigbjorn.skjaeret@scala.com> * grammar : improve regex when naming ref derived rules * grammar : replace non-conformant definitions array with anyOf test case --------- Co-authored-by: Sigbjørn Skjæret <sigbjorn.skjaeret@scala.com> # Conflicts: # tests/test-json-schema-to-grammar.cpp * merge fix * llama : minor grammar refactor (ggml-org#10897) * llama: fix error on bad grammar (ggml-org#12628) * grammar : fix integer overflow (ggml-org#17381) * Fix DoS / integer overflow * Remove optional, use INT64_MAX instead as placeholder value (it's technically -1, so it fits :) * White space * Actually, since it's unsigned, use UINT64_MAX # Conflicts: # src/llama-grammar.cpp * grammar: fix regression caused by ggml-org#17381 (ggml-org#17412) * grammar: fix regression caused by ggml-org#17381 * more readable # Conflicts: # src/llama-grammar.cpp * Merge Fix * Fix warnings --------- Signed-off-by: David Korczynski <david@adalogics.com> Co-authored-by: Joe Eli McIlvain <joe.eli.mac@gmail.com> Co-authored-by: Georgi Gerganov <ggerganov@gmail.com> Co-authored-by: frob <rick+github@frob.com.au> Co-authored-by: Richard Lyons <frob@cloudstaff.com> Co-authored-by: DavidKorczynski <david@adalogics.com> Co-authored-by: Daniel Bevenius <daniel.bevenius@gmail.com> Co-authored-by: firecoperana <firecoperana> Co-authored-by: Sigbjørn Skjæret <sigbjorn.skjaeret@scala.com> Co-authored-by: Aldehir Rojas <hello@alde.dev> Co-authored-by: Olivier Chafik <olivier.chafik@gmail.com> Co-authored-by: Piotr Wilkin (ilintar) <piotr.wilkin@syndatis.com> Co-authored-by: Xuan-Son Nguyen <son@huggingface.co> Co-authored-by: Iwan Kawrakow <iwan.kawrakow@gmail.com>
Anico2
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Jan 15, 2026
* grammar: fix regression caused by ggml-org#17381 * more readable
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Ref: #17381 (comment)
uint64_tto align with the rest of the code base