RE: [PATCH] kbuild: treat char as always signed

David Laight
2022-10-19T21:07:07Z

From: Linus Torvalds
> Sent: 19 October 2022 19:11
...
> Explicit casts are bad (unless, of course, you are explicitly trying
> to violate the type system, when they are both required, and a great
> way to say "look, I'm doing something dangerous").

The worst ones in the kernel are the __force ones for sparse.
They really ought to be a function (#define) so that they
are not seen by the compiler at all.
Otherwise they can hide a multitude of sins.

There are also the casts to convert integer values to/from unsigned.
and to different sized integers.
They all happen far too often and can hide things.
A '+ 0u' will convert into to unsigned int without a cast.
Casts really ought to be rare.
Even the casts to from (void *) (for 'buffers') can usually be
made implicit in a function call argument.

David

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