[PATCH v2 0/2] Stop some of the abuse of BUG() where compile time checks should be used.

From: David Daney
Date: Tue Nov 22 2011 - 13:14:57 EST


From: David Daney <david.daney@xxxxxxxxxx>

New for v2:

As suggested by 'DM', call the macro BUILD_BUG() instead of
BUILD_BUG_ON_USED(). Linus seemed satisfied with this, so if it still
looks good, can we put it in some linux-next tree (Perhaps Andrew
Morton's) to cook for a while?

The second patch now covers linux/huge_mm.h too.

>From v1:

After some, perhaps justified, reluctance to merge dummy
symbol definitions containing BUG() into header files, I propose
these patches instead.

We define a new compile time assertion BUILD_BUG_ON_USED() that can
be used in places were we expect the compiler's dead code
elimination to get rid of code. This happens mostly in code
dealing with huge pages, but in other places as well.

The first patch adds BUILD_BUG_ON_USED(), the second gets rid of
one of the main abusers of BUG().

David Daney (2):
kernel.h: Add BUILD_BUG() macro.
hugetlb: Replace BUG() with BUILD_BUG() for dummy definitions.

include/linux/compiler-gcc4.h | 1 +
include/linux/compiler.h | 4 +++-
include/linux/huge_mm.h | 8 ++++----
include/linux/hugetlb.h | 14 +++++++-------
include/linux/kernel.h | 16 ++++++++++++++++
5 files changed, 31 insertions(+), 12 deletions(-)

--
1.7.2.3

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/