C89 might be ancient, but Visual Studio still doesn't support C99 fully. Neither do some other vendor compilers. If you want to write portable C code, you either have to limit your supported compiler to GCC or avoid some C99 features.

Since when has VS-compatibility been such a high priority for Perl development?

Given that there are vast tracts of Perl source that need to be conditionally compiled for different OSs, the requirement that some gcc-enabled C99 syntax might need additional effort for VS is neither here nor there.

That said, as of this month, even gcc doesn't do all of C99. But that's no good reason to restrict the use of features that have been common extensions to virtually every C compiler since long before C99 was ratified.

---

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.

"Science is about questioning the status quo. Questioning authority".

In the absence of evidence, opinion is indistinguishable from prejudice.

RIP an inspiration; A true Folk's Guy