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0 pointsmoonchild5y ago0 comments

With standard VLAs, you always have a guarantee of being able to access sizeof(buf) bytes from buf, for any variable buf. With your syntax, that guarantee would no longer hold, unless c had dependent types that could prove said guarantee.

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kiwidrew5y ago

Well, given that C is fundamentally about separate compilation and external linkage, most "guarantees" in the language are really just promises or contracts. As demonstrated in david2ndaccount's comment, standard C already handles VLA function arguments just fine (without any need for dependent types).

The only issue is that C99 insists that the first dimension of an array argument must decay to a pointer, discarding the associated type information of that array's dimension.

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0 pointsmoonchild5y ago0 comments

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kiwidrew5y ago

The only issue is that C99 insists that the first dimension of an array argument must decay to a pointer, discarding the associated type information of that array's dimension.

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