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SubjectRe: [2.6 patch] drivers/net/smc-mca.c: cleanups
Date
Arjan van de Ven <arjan@infradead.org> wrote:
>
>> I've used this technique in a few very
>> small programs to reduce their size (I could strip off both their bss and
>> data sections to save space). Also, I believe that the compiler is able
>> to optimize code using consts, but this is pure speculation, I've not
>> verified it.
>
> Afaik that's the main difference between C and C++; in C you can still
> change "const" variables... in C++ thats illegal (at least that's what I
> remember and google seems to support somewhat ;)

The compiler does use the const modifier on a static object to optimise
code. Try compiling this program:

const int x;

int bar(int);

int foo(void)
{
bar(x);
return bar(x);
}
With the const gcc (3.3.4) will only load x once while it'll reload
it after calling bar if you remove the const modifier.
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