Weird Problem

[carbonBased]

you don't need all that..

Code: Select all

unsigned char cpu_sign[13] = {0};

this will initialize the entire array to zero.

If I recall the C standard correctly, this is only true for static arrays. Since cpu_sign isn't static, the remainder of the array (1 to 12) is undefined.

--Jeff

[mrd]

If I recall the C standard correctly, this is only true for static arrays. Since cpu_sign isn't static, the remainder of the array (1 to 12) is undefined.

According to both of my references, K&R C and C99, if there are fewer initializers than members of an aggregate (which includes arrays), then remaining members are implicity initialized to zero, the same as static aggregate members are.

[carbonBased]

Well I'd, of course, trust K&R over my memory

A lot of compilers don't fully support C99 yet (unfortunately), but if it's listed in K&R... and empirical evidence shows that GCC certainly behaves this way.

Cheers,
Jeff

[Da_Maestro]

The size increase you get when you initialise variables is small compared to the benefit you get from maintainability. Of course I wouldn't recommend intialising entire arrays (like page tables), but for small arrays like this a little benefit goes a long way in the future.

I say that succession planning holds the key to producing a stable and robust OS. If your current kernel *only just* manages to run, then what hope do future versions of your OS have?

We don't want to re-invent M$Win here.