[astrange]

The C spec is certainly not formal or precise.

https://www.ralfj.de/blog/2020/12/14/provenance.html

Another example is that it's unclear from the standard if you can write malloc() in C.

[butterNaN]

Sure but the point OP is making is that it is still more spec'd than most real world problems

[astrange]

You're welcome to try writing a C compiler and standard library doing no research other than reading the spec.