Re: [PATCH] sequencer: shut up clang warning

From: Jeff King <peff@peff.net>
Date: Nov 9, 2016, 15:37 UTC
Message-ID: <20161109153733.iauja57zikyb2awv@sigill.intra.peff.net>
In-Reply-To: <efbba4b32515fed7096c1c81dbe97eedd44083b0.1478699713.git.johannes.schindelin@gmx.de>

On Wed, Nov 09, 2016 at 02:56:25PM +0100, Johannes Schindelin wrote:

Show 12 quoted lines

> When comparing a value of type `enum todo_command` with a value that is
> outside the defined enum constants, clang greets the developer with this
> warning:
> 
> 	comparison of constant 2 with expression of type
> 	'const enum todo_command' is always true
> 
> While this is arguably true *iff* the value was never cast from a
> free-form int, we should keep the cautious code in place.
> 
> To shut up clang, we simply introduce an otherwise pointless enum constant
> and compare against that.

This does silence the warning.

I slightly prefer mine because:

  1. It does not carry an implicit requirement that TODO_INVALID remain
     the final enum value.

  2. It also protects the range check against a negative enum value.

But this is code that is getting changed later by you anyway, and I do not care that strongly.

-Peff