Hi Dave, On Wed, Nov 30, 2016 at 10:25:49AM +1100, Dave Chinner wrote: > > So, builddefs.in should really detect if autoconf set a "large file > required" flag, and in that case add the _FILE_OFFSET_BITS value > that autoconf has generated to the PCFLAGS variable, right? (PCFLAGS > are "Platform CFLAGS") > > Or, if we are just going to unconditionally define > -D_FILE_OFFSET_BITS=64 in CFLAGS, then the autoconf checks are > completely useless and should be removed? > I don't believe it's possible to use the results of AC_SYS_LARGEFILE without using a config header that is included *first* in all .c files. So the other option is to define _FILE_OFFSET_BITS=64 ourselves in CFLAGS. (Or PCFLAGS for just the platforms that need it; I know it's needed on 32-bit Linux, but I don't know about other platforms.) And yes, in that case the autoconf macros are useless and should be removed. Sorry for not explaining more in the commit message --- I hadn't looked into the details of what was going on with the autoconf macros (or that they were recently added, for that matter) until you pointed them out. Eric > > The reason AC_NEED_LFS still passes is that 'configure' includes a > > temporary header confdefs.h rather than the final generated > > header, and the temporary header includes the _FILE_OFFSET_BITS > > definition. > > IOWs, stupid code backed by ambiguous documentation means that > developers that try to do the right thing still end up with broken > builds. > > Eric, to speed things up a bit next time, can you try to explain how > something is broken in the commit message, not just say "it's > broken, fix it". This avoids the need to go back and forth multiple > times just so we can understand what the problem is that you are > fixing.... > > Cheers, > > -Dave. > -- > Dave Chinner > david@xxxxxxxxxxxxx -- To unsubscribe from this list: send the line "unsubscribe linux-xfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
