krb4 library major version bump
Jacques A. Vidrine
nectar at celabo.org
Fri Feb 7 08:07:33 EST 2003
On Fri, Feb 07, 2003 at 02:46:07AM -0500, Tom Yu wrote:
> >>>>> "raeburn" == Ken Raeburn <raeburn at MIT.EDU> writes:
> raeburn> Currently, aklog is crashing for me while printing an error message.
> raeburn> It's getting the error message by indexing into krb_err_txt. In
> raeburn> previous releases, this was a char* array. Now it's a char**.
> raeburn> That's another incompatible change. Tom checked it in in December as
> raeburn> part of merging some of the Mac code. Is this change required?
> Hm. It used to be
> const char *const krb_err_txt ;
> which is an array of const pointers to const char, and now it's
> const char * const * const krb_err_txt;
> which is a const pointer to const pointer to const char.
> I think the only significant differences have to do with the
> qualifiers, since an array type should be equivalent to a const
> pointer to its member type. I'm still puzzled as to why that would
> cause a problem.
> The reason the change is needed is that we're doing a gross hack to
> get krb_err_txt from the generated krb_err.c. Is there an actual ABI
> difference between (const char * const ) and (const char * const * const)?
> That would seem rather broken.
I'm not sure to what code this is in reference, but you cannot define
a symbol as an array in one file and declare it as a pointer in
krb.c: const char *const krb_err_txt ;
krb.h: const char * const * const krb_err_txt;
will cause undefined behavior because the pointer arithmetic will be
wrong in consumers of <krb.h>.
Jacques A. Vidrine <nectar at celabo.org> http://www.celabo.org/
NTT/Verio SME . FreeBSD UNIX . Heimdal Kerberos
jvidrine at verio.net . nectar at FreeBSD.org . nectar at kth.se
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