I'm using this gist to collect a bunch of BNF grammars I've written, extracted, or found across the web. All of them are representations of existing languages. I found them useful, someone else might as well
C
c-grammar.bnf
- An incomplete representation of the C language in BNF (from 1988, all newer versions I could find were EBNF or PEG. Let me know if you have a better one.)
Adapted from The C Programming Language, 2nd edition, by Brian W. Kernighan and Dennis M. Ritchie,Prentice Hall, 1988.