On Thu, Nov 09, 2023 at 11:52:33AM -0800, Darrick J. Wong wrote: > > +#ifndef BUILD_BUG_ON_MSG > > +#define BUILD_BUG_ON_MSG(a, b) BUILD_BUG_ON(a) > > How difficult would it be to port the complex kernel macros that > actually result in the message being emitted in the gcc error output? > > It's helpful that when the kernel build breaks, the robots will report > exactly which field/struct/whatever tripped, which makes it easier to > start figuring out where things went wrong on some weird architecture. I did try to pull the entire compile time assert machinery from the kernels compiler_types.h in, especially as atomic.h already uses a differnet part of it. After it pulled in two more depdendencies I gave up, but in principle it should be entirely doable. > Otherwise I'm all for porting xfs_ondisk.h to xfsprogs. IIRC I tried > that a long time ago and Dave or someone said xfs/122 was the answer. I'd much prefer to do it in C code and inside the libxfs we build. If we can agree on that and on killing off xfs/122 I'll look into porting the more complex compile time assert. The other option would be to switch to using static_assert from C11, which doesn't allow a custom message, but at least the default message isn't confusing as hell.
