c - Does Comments/Identifiers can impact on code performance/operability? -

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today presented wiered fact (or not)

it said:
"at disallowed write long, descriptive identifier names, , forbidden write comments linux drivers written in ansi c."

when asked "wtf? why?" told caused performence issues , errors of such...
not many details there.

i supprised, have ask...
can real?
knowing comments stripped compilation pre-processor,
, identifiers either way converted adresses.

so... can cause problems ?

well, ansi c standard, , standard must follow (i mean compiler designers , programmers, if decide support it).

ansi c standard states exported identifiers (yeah, exported identifiers stored symbols in symbols table is, not addresses) must not longer 6 characters, , non-exported identifiers ok not longer 31 character.

on commenting. except obvious pitfalls accidental code swallowing multi-line commenting, recommend read coding style article kernel developers explains kind of comments not encouraged.


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