[PATCH xquartz 04/10] randr: Silence -Wshift-negative-value warnings

Alan Coopersmith alan.coopersmith at oracle.com
Wed Oct 14 15:33:19 PDT 2015

On 10/14/15 03:13 PM, Jeremy Huddleston Sequoia wrote:
> rrtransform.c:199:23: warning: shifting a negative signed value is undefined [-Wshift-negative-value,Semantic Issue]
>              rot_cos = F(-1);

> -            rot_cos = F(-1);
> +            rot_cos = F(~0u);

Is -1 guaranteed to be ~0u on all platforms?   Or just all the ones we know
and care about?

Would it be better to instead do:
-#define F(x)    IntToxFixed(x)
+#define F(x)    IntToxFixed((uint32_t) x)

in randr/rrtransform.c ?

	-Alan Coopersmith-              alan.coopersmith at oracle.com
	 Oracle Solaris Engineering - http://blogs.oracle.com/alanc

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