Ambiguous C?
Dave Brower
daveb at gonzo.UUCP
Sun Apr 30 04:09:12 AEST 1989
In article <9249 at alice.UUCP> ark at alice.UUCP (Andrew Koenig) suggests:
>To suppress the optimization, you can probably conceal the
>value of SCU_BDID from the compiler by using it in a way that
>the compiler thinks might change. For instance:
>
> static int SCU_BDID = 0x2000;
>
>Now the compiler probably won't be smart enough to realize that
^^^^^^^^
>SCU_BDID is really a constant, so it will have to generate code
>that caters to any bit in the whole word being on.
Since it is static, the compiler might be able to figure it out.
To get a higher degree of confidence, you can remove the static, showing
the compiler that some other file might know about the variable and
change it.
-dB
--
"An expert is someone who's right 75% of the time"
{sun,mtxinu,amdahl,hoptoad}!rtech!gonzo!daveb daveb at gonzo.uucp
More information about the Comp.lang.c
mailing list