[patch 1/3] Add BSS to resource tree
sam at ravnborg.org
Thu Oct 18 18:18:13 EDT 2007
On Fri, Oct 19, 2007 at 12:00:48AM +0200, Andi Kleen wrote:
> On Thu, Oct 18, 2007 at 11:58:27PM +0200, Sam Ravnborg wrote:
> > On Thu, Oct 18, 2007 at 11:48:37PM +0200, Andi Kleen wrote:
> > > > > +extern char _text, _end, _etext, _edata, _bss;
> > > >
> > > > These should be in a header file.
> > >
> > > Normally the "no externs in .c" rule doesn't apply to assembler or linker
> > > script defined labels. That's because the point of the header file is to
> > > type check them, but there is nothing to type check here.
> > For linker generated symbols we have sections.h for this purpose.
> > The above symbols are all available if we do an:
> > #include <asm/sections.h>
> > This is the right fix in this case.
> The problem is that they're often the wrong type here. E.g. wrong signedness
> etc. I ran into problems in the past where using this required ugly casts.
But then we should fix them instead of working around the problem - no?
Grepping for _text shows that there are plenty of different ways to declare
that symbol extern - this does not look correct.
And I recall that extern char sym is considered correct by binutils
people - but I'm not 100% sure and google did not give me an appropriate hit.
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