Re: OSX doesn't accept identical source/target for strcpy() anymore - Mailing list pgsql-hackers

From Peter Geoghegan
Subject Re: OSX doesn't accept identical source/target for strcpy() anymore
Date
Msg-id CAM3SWZTBtqdSAAVGJUhp2en4yf6R+E1sG_YvfXPCq6nzqk9ZEg@mail.gmail.com
Whole thread Raw
In response to Re: OSX doesn't accept identical source/target for strcpy() anymore  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: OSX doesn't accept identical source/target for strcpy() anymore  (Peter Eisentraut <peter_e@gmx.net>)
List pgsql-hackers
On Mon, Oct 28, 2013 at 6:11 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Both gcc and glibc have been moving steadily in the direction of
> aggressively exploiting "undefined behavior" cases for optimization
> purposes.  I don't know if there is yet a platform where strncpy with
> src == dest behaves oddly, but we'd be foolish to imagine that it's
> not going to happen eventually.  If anything, Apple is probably doing
> us a service by making it obvious where we're failing to adhere to spec.

It's worth being aware of the fact that the upcoming GCC 4.9 release
is expected to ship with an "Undefined Behavior Sanitizer", as
described here:

http://gcc.gnu.org/gcc-4.9/changes.html

-- 
Peter Geoghegan



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