Re: [PATCH] warning: `__attribute_used__' redefined

[Daniel Jacobowitz <dan@debian.org>]

On Tue, Feb 10, 2004 at 08:31:24AM -0800, Linus Torvalds wrote:
> 
> 
> On Tue, 10 Feb 2004, Andrew Morton wrote:
> > 
> > ah, thanks.
> > 
> > Like this?
> 
> That will just break. The reason for the "compiler.h" include is the 
> "__user" part of fpstate, so now you'll get a parse error later if 
> non-kernel code includes this.
> 
> So the rule should still be: don't include kernel headers from user 
> programs. But if it's needed for some reason, that #ifdef needs to be 
> somewhere else (inside "compiler.h" or something).

This is what Debian has been using.  I believe the other folks with a
glibc-kernel-headers package based on 2.6 do something similar.  I
don't know how you'll feel about adding this sort of crap to the
kernel, though.  Someone else needs to find time to start linuxabi
moving again...

--- include/linux/compiler.h	2003-10-15 11:13:09.000000000 -0400
+++ include/linux/compiler.h.t	2003-11-01 18:04:19.000000000 -0500
@@ -9,6 +9,15 @@
 # define __kernel
 #endif
 
+#if !defined(__KERNEL__)
+/* Debian: Most of these are inappropriate for userspace.  */
+/* We don't define likely, unlikely, or barrier; they're namespace-intrusive
+   and should not be needed outside of __KERNEL__.  For __attribute_pure__
+   and __attribute_used__ we use glibc's definitions.  */
+# include <sys/cdefs.h>
+# define __deprecated
+#else
+
 #if __GNUC__ > 3
 # include <linux/compiler-gcc+.h>	/* catch-all for GCC 4, 5, etc. */
 #elif __GNUC__ == 3
@@ -86,4 +95,6 @@
     (typeof(ptr)) (__ptr + (off)); })
 #endif
 
+#endif /* __KERNEL__ */
+
 #endif /* __LINUX_COMPILER_H */

-- 
Daniel Jacobowitz
MontaVista Software                         Debian GNU/Linux Developer