Messages in this thread | | | From | David Howells <> | Subject | using void variables as linker-script symbol refs | Date | Fri, 10 Oct 2003 18:49:28 +0100 |
| |
I've got a situation in which I'd like to use something like the following to refer to constants defined in the linker script:
extern const void _stext, _etext;
#define __kernel_size ((unsigned long)&_etext - (unsigned long)&_stext)
Rather than:
extern int _stext, _etext;
Or:
extern int _stext[], _etext[];
Or:
struct __not_really_a_struct; struct __not_really_a_struct _stext, _etext;
This has a couple of advantages:
(1) You can't accidentally read/set such variables directly.
(2) GCC doesn't assume they can be referenced by register-relative means, if the CPU has a special data pointer (such as a small-data pointer).
Any thoughts? Or is this just a straight forward shooting offence?
David - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |