[cairo] compiler warnings in cairo_wideint.h/c

Andreas Tobler toa at pop.agri.ch
Wed Oct 13 13:38:04 PDT 2004

Keith Packard wrote:

> Around 8 o'clock on Oct 13, "Andreas Tobler" wrote:
>>/* Type qualifiers on a function return type are
>>   normally permitted by the standard but have no
>>   effect.
> Hmm.  The effect I was trying to induce was to teach the compiler that 
> given fixed arguments, these functions always return the same result 
> (i.e., they are "pure" functions).  I thought that's what the 'const' 
> qualifier on the return value did.

Not quite, the const has only a meaning in terms of compile time issue.
e.g, you can say 'const int a = 10;' Then the compiler assigns 'a' a ten 
(value 10).
At runtime the const has no influence. Only if someone outside your 
program/application is modifying the 'a'. (e.g) a hw issue.

Your program/application can not modify const's.
And a function is meant to be modifying at runtime.

This is my understanding of using const.

If I'm wrong, please tell me.

Maybe, you may get something out of using 'static'.


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