Windows: `Maximum call stack size exceeded` when number of items in `anyOf` is more than 1700

I have a schema where one of the field km04 is having 1700+ options, whenever I am trying to validate the object send from client, with 1700+ options for the km04 field, it is specifically throwing an error in windows for Maximum call stack, this error is not replicable in mac, or even in windows if we reduce the number of options available for the km04 field below 1700.

here is the sample schema, schema.txt

The version of Ajv you are using 6.12.3

The environment you have the problem with Windows

Your code (please make it as small as possible to reproduce the issue) ajv.validate(schema, body);

If your issue is in the browser, please list the other packages loaded in the page in the order they are loaded. Please check if the issue gets resolved (or results change) if you move Ajv bundle closer to the top It is not in browser

Results in node.js v8+ Maximum call stack size exceeded

Results and error messages in your platform

Maximum call stack size exceeded

\node_modules\\ajv\\lib\\compile\\index.js:120:26)
   at Ajv.compile (\node_modules\\ajv\\lib\\compile\\index.js:55:13)
   at Ajv._compile (\node_modules\\ajv\\lib\\ajv.js:348:27)
   at Ajv.validate (\node_modules\\ajv\\lib\\ajv.js:96:36)

[epoberezkin]

yes, semantically they are equivalent in this case (value is noop, it’s just metadata that can be provided some other way, e.g. as a map), but the generated code is very different (and enum is way more efficient).

[epoberezkin]

It’s a fundamental call stack depth restriction given which code ajv has to generate without allErrors mode. I am quite reluctant to make compilation asynchronous to be honest…

One more idea is to simply increase the call stack size in nodejs (not 100% sure how many calls it makes per schema level as it compiles, but probably less than 10, so 10-20k should be enough) - please let me know if you try it what stack size makes it compile without any other changes.