Re: [RFC] bloody mess with __attribute__() syntax

From: Al Viro
Date: Thu Jul 05 2007 - 12:43:48 EST


On Thu, Jul 05, 2007 at 08:36:35AM -0700, Josh Triplett wrote:
> Wow. Insane. So these all declare the same type:
> __attribute__((foo)) T *v;
> T __attribute__((foo)) *v;
> T *__attribute__((foo)) v;
> ? Specifically, they point to a foo-T, for convenient shooting?

They all give you foo-pointer-to-T.
T (__attribute__((foo)) *v);
would give pointer-to-foo-T.

> context also represents a qualifier; the position of the qualifier should
> determine things like whether you want to enforce the context when you access
> a pointer or dereference a pointer.

Since __context__ is (sparse-only) keyword, we are not constrained by
anything anyway.

> > Frankly, I would rather add a new primitive (__qualifier__) mirroring the
> > __attribute__, but acting like real qualifiers do. And switched the
> > noderef et.al. to it.
>
> Something like that sounds vaguely reasonable. It should allow the same set
> of attributes, and just change what they apply to. To use your example,
> T __qualifier__((foo)) *v;
> and
> T (__attribute__((foo)) *v);
> would mean the same thing.

Yup, except that it would not accept storage-class-like attributes (e.g.
always_inline). And yes, __qualifier__((context(...))) probably might
be a replacement for __context__, to reduce the number of primitives.
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