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From: | "Stephen J. Turnbull" <turnbull AT sk DOT tsukuba DOT ac DOT jp> |
To: | djgpp AT delorie DOT com |
Subject: | Re: _CRT0_FLAG_NULLOK |
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Date: | Thu, 01 Aug 2013 19:04:45 +0900 |
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Rod Pemberton writes: > E.g., [C definition committees] could've specified a NULL pointer > always points to an emtpy string of just a null character. Such a > specification is unlikely to break C, since a NULL pointer just > needs to have a unique address. This would've allowed a NULL > pointer to safely function as an empty character string too. Which is an arbitrary decision, because it could be a pointer to an arbitrary instance of *any* type. Of course some of those instances may be compatible with an empty string, but I don't see how you can guarantee they *all* will be, on all machines you might want to target with a C compiler. Even if you restrict them to be "do nothing" instances. (Eg, the numeric types have *two* do-nothing instances, 0 and 1, depending on the operation.) So the decision to favor strings is arbitrary.
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