POSIX _t Namespace Conflict about wasm-c-api HOT 5 OPEN

Hm, interesting, but the way I read it is that the restrictions stated there constrain implementations of POSIX and what implementation-specific symbols they can add to POSIX header files. AFAICS they do not constrain third-party libraries with independent header files.

For the Wasm API, all C names have consciously been given a wasm_ prefix, so I expect the potential for conflict to be minimal to non-existent.

from wasm-c-api.

The suffix is reserved for all POSIX and C headers. (Note the [CX], which means it's extending the C standard, which means its reserving for C headers as well.) If your code never includes a header like <stdlib.h>, then you're good. I've written C source file that didn't include any C or POSIX header. But if your code includes such a header and also defines identifiers (directly or indirectly) with the _t suffix, then there's potential for namespace clash, especially if you're defining them in headers to be used by other applications.

In practice few people know this, let alone obey it. But I figured standards should probably be neighborly.

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Sigh, modularity and name spacing are such a sad story in C.

The only unqualified type names we define are the byte_t, float32_t, and float64_t synonyms. I agree that we should probably avoid those. (It's unfortunate that they do not exist in any standard header.)

For everything else I don't know. We indeed include some C headers. However, as mentioned, all our names are sanitised with wasm_ prefixes. If POSIX makes such a sweeping land grab in the C name space that it even prevents harmless uses like that -- and generally is in conflict with large parts of dev reality -- then I don't know if third parties should feel obliged to obey to the letter. And I'm saying that as a person who usually very much prefers conforming to standards

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FWIW, the use of _t in the API doesn't really add anything. For years, before I read and understood the standards, I thought _t was an idiom for scalar typedefs (integers, pointers) or more generally (in my rationalizations) POD types that could be copied by simple assignment, and that's how I always used it. IME most software that uses _t rarely uses it for aggregate objects like structs or unions. What originally clued me into the issue was how the pthreads API uses _t for aggregate objects, including ones that couldn't be copied, which seemed irregular until I learned that the whole point of _t was for namespacing, not readability.

That said, I only wanted to bring the issue to your attention. I don't care to bikeshed style. Feel free to dispose of this issue however you want ;)

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Actually, the main benefit of the convention from my perspective is that you don't get into syntactic issues where you want to name a variable or function after a type, because C syntax does not properly separate the name spaces.

Anyway, thanks for bringing this up. I at least want to reconsider the use of unqualified type names.

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