On Wed, 15 Oct 2014 12:52:44 -0700 Joe Perches <[email protected]> wrote:
> On Wed, 2014-10-15 at 12:50 -0700, Andrew Morton wrote: > > On Wed, 15 Oct 2014 12:45:48 -0700 Joe Perches <[email protected]> wrote: > > > > > On Wed, 2014-10-15 at 12:42 -0700, Andrew Morton wrote: > > > > On Wed, 15 Oct 2014 12:32:08 -0700 Joe Perches <[email protected]> wrote: > > > > > > > > > Using weak can have unintended link defects. > > > > > Emit an error on its use. > > > > > > > > Well, we don't want a warning about use of __weak in function > > > > definitions. Only in declarations. > > > > > > Why is that? > > > > Because the problem we're trying to detect is when __weak is used on a > > declaration. > > > > This is OK: > > > > foo.h: > > extern int foo(void); > > foo.c: > > int __weak foo(void) > > { > > ... > > } > > > > But this is not OK: > > > > foo.h: > > extern __weak int foo(void); > > foo.c: > > int __weak foo(void) > > { > > ... > > } > > > > And this? > > foo.c: > > extern __weak int foo(void); > > int __weak foo(void) > { > } > That's why I just said "And this bit maybe is checking for use in a header file, which is not as good as checking for a declaration but is probably good enough." I don't think that would trigger the bug anyway. The problem is that extern __weak int foo(void); int foo(void) { } unexpectedly and undesirably turns foo() into __weak. I think it would be sufficient to check for __weak in a declaration. If that isn't practical then checking for __weak in a .h file should suffice. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
