| Message ID | 1351457835-7553-8-git-send-email-daniel.santos@pobox.com (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
On Sun, Oct 28, 2012 at 03:57:14PM -0500, danielfsantos@att.net wrote: > Add BUILD_BUG_ON_MSG which behaves like BUILD_BUG_ON (with optimizations > enabled), except that it allows you to specify the error message you > want emitted as the third parameter. Under the hood, this relies on > _BUILD_BUG_INTERNAL, which does the actual work and is pretty-much > identical to BUILD_BUG_ON. > > Signed-off-by: Daniel Santos <daniel.santos@pobox.com> > --- > include/linux/bug.h | 22 ++++++++++++++++++++++ > 1 files changed, 22 insertions(+), 0 deletions(-) > > diff --git a/include/linux/bug.h b/include/linux/bug.h > index 6c38988..3bc1ddf 100644 > --- a/include/linux/bug.h > +++ b/include/linux/bug.h > @@ -16,6 +16,7 @@ struct pt_regs; > #define BUILD_BUG_ON_NOT_POWER_OF_2(n) > #define BUILD_BUG_ON_ZERO(e) (0) > #define BUILD_BUG_ON_NULL(e) ((void*)0) > +#define BUILD_BUG_ON_MSG(cond, msg) (0) > #define BUILD_BUG_ON(condition) (0) > #define BUILD_BUG() (0) > #else /* __CHECKER__ */ > @@ -38,6 +39,27 @@ struct pt_regs; > */ > #define BUILD_BUG_ON_INVALID(e) ((void)(sizeof((__force long)(e)))) > > +#define __BUILD_BUG_INTERNAL(condition, msg, line) \ > + do { \ > + extern void __build_bug_on_failed_ ## line \ > + (void) __compiletime_error(msg); \ > + __compiletime_error_fallback(condition); \ > + if (condition) \ > + __build_bug_on_failed_ ## line(); \ > + } while (0) > + > +#define _BUILD_BUG_INTERNAL(condition, msg, line) \ > + __BUILD_BUG_INTERNAL(condition, msg, line) Stupid question: can BUILD_BUG_ON and BUILD_BUG_ON_MSG both use __BUILD_BUG_INTERNAL? In the BUILD_BUG_ON msg will be "BUILD_BUG_ON failed" and line empty. Can that even work? Thanks.
On Tue, Oct 30, 2012 at 06:17:47PM +0100, Borislav Petkov wrote: > can BUILD_BUG_ON and BUILD_BUG_ON_MSG both use __BUILD_BUG_INTERNAL? > > In the BUILD_BUG_ON msg will be "BUILD_BUG_ON failed" and line empty. > Can that even work? Yes it can, I should simply look at patch 9/9 first :-).
diff --git a/include/linux/bug.h b/include/linux/bug.h index 6c38988..3bc1ddf 100644 --- a/include/linux/bug.h +++ b/include/linux/bug.h @@ -16,6 +16,7 @@ struct pt_regs; #define BUILD_BUG_ON_NOT_POWER_OF_2(n) #define BUILD_BUG_ON_ZERO(e) (0) #define BUILD_BUG_ON_NULL(e) ((void*)0) +#define BUILD_BUG_ON_MSG(cond, msg) (0) #define BUILD_BUG_ON(condition) (0) #define BUILD_BUG() (0) #else /* __CHECKER__ */ @@ -38,6 +39,27 @@ struct pt_regs; */ #define BUILD_BUG_ON_INVALID(e) ((void)(sizeof((__force long)(e)))) +#define __BUILD_BUG_INTERNAL(condition, msg, line) \ + do { \ + extern void __build_bug_on_failed_ ## line \ + (void) __compiletime_error(msg); \ + __compiletime_error_fallback(condition); \ + if (condition) \ + __build_bug_on_failed_ ## line(); \ + } while (0) + +#define _BUILD_BUG_INTERNAL(condition, msg, line) \ + __BUILD_BUG_INTERNAL(condition, msg, line) + +/** + * BUILD_BUG_ON_MSG - break compile if a condition is true & emit supplied + * error message. + * @condition: the condition which the compiler should know is false. + * + * See BUILD_BUG_ON for description. + */ +#define BUILD_BUG_ON_MSG(cond, msg) _BUILD_BUG_INTERNAL(cond, msg, __LINE__) + /** * BUILD_BUG_ON - break compile if a condition is true. * @condition: the condition which the compiler should know is false.
Add BUILD_BUG_ON_MSG which behaves like BUILD_BUG_ON (with optimizations enabled), except that it allows you to specify the error message you want emitted as the third parameter. Under the hood, this relies on _BUILD_BUG_INTERNAL, which does the actual work and is pretty-much identical to BUILD_BUG_ON. Signed-off-by: Daniel Santos <daniel.santos@pobox.com> --- include/linux/bug.h | 22 ++++++++++++++++++++++ 1 files changed, 22 insertions(+), 0 deletions(-)