Re: Upraded from 7.0.1 to 7.0.2 --> could not run ELF binary

On Thu, Nov 03, 2016 at 12:13:52PM +1000, Ray Phillips wrote:
> Thanks for responding Hubert and Stephen.  Unfortunately it turns out
> I was wasting your time.  I do have the old binaries (which were
> compiled on 7.0.1) but I've discovered they're x86-64 binaries.  I
> must have upgraded an amd64 7.0.1 system (on a USB key in this case)
> to i386 7.0.2. :(
> 
> BTW, a few years ago I upgraded an i386 system (I'm not sure what the
> pre and post upgrade versions were now) and afterwards sendmail didn't
> run properly.  Recompiling the sleepycat database and sendmail cured
> the problem that time.  That system had been upgraded several times
> before without any issues.  Is it generally wise to expect programs
> will need to be recompiled when going from one major version number to
> another?  Is there any way to check if it'll be necessary before doing
> the upgrade?
> 
> 
> Ray

For *most* things, there is a strong emphasis on backwards compatibility.
To the point that if you upgrade a NetBSD 1.5 system to NetBSD 7.99.x,
and some program fails to run, it will be probably considered a bug.