Re: mmotm 2009-04-24-18-14 uploaded - NVidia indigestion

From: Nick Piggin
Date: Wed Apr 29 2009 - 03:03:31 EST


On Tue, Apr 28, 2009 at 12:01:21PM -0400, Valdis.Kletnieks@xxxxxx wrote:
> On Tue, 28 Apr 2009 08:15:57 +0200, Nick Piggin said:
>
> Here's the code (pretty much *all* the code):
>
> > #include <linux/version.h>
> > #include <linux/utsname.h>
> > int main() {
> > if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,0)) {
> > return 0;
> > } else {
> > return 1;
> > }
> > }
>
> > Hmm, yes if you build without -O, then it appears like the compiler
> > trips over this. I wouldn't be unhappy with just removing the BUILD_BUG_ON,
> > but shouldn't the module be using -O[s2]?
>
> It's a little autoconfig chunk from vendor code that determines if we're
> building on a sane/recent kernel. Not the sort of thing you'd expect to
> need to invoke the frikking optimizer for program *correctness* :)

The kernel I think has for a long time required -O to compile correctly
because some things marked inline have had to be inlined for correctness.
This might have changed now that we have __always_inline, but anyway.

But I'll just get rid of that BUILD_BUG_ON.

Thanks,
Nick
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