https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110617
--- Comment #9 from Florian Weimer <fw at gcc dot gnu.org> ---
(In reply to Xi Ruoyao from comment #6)
> (In reply to Richard Biener from comment #5)
> > I think a -f... option to disable the code generation effects would make
> > more sense than adding another attribute kind.
>
> Then maybe we'd just add a -D_GLIBC_NONNULL={0,1} (?) into Glibc cdefs.h
> instead. Anyway I'm already too frustrated about this so I'll not continue
> working on nonnull within Glibc headers. If you don't like this just close
> it as WONTFIX.
For those who are not following libc-alpha, glibc already disables __nonnull
during its build, so it should be totally fine to use __nonnull in installed
headers to improve diagnostics.
We have this in include/sys/cdefs.h (which augments <sys/cdefs.h>):
/* The compiler will optimize based on the knowledge the parameter is
not NULL. This will omit tests. A robust implementation cannot allow
this so when compiling glibc itself we ignore this attribute. */
# undef __nonnull
# define __nonnull(params)
We'd like the diagnostics for building glibc itself, and a new -f option would
help with that.
