On Mon, Mar 19, 2018 at 10:32 AM, Thomas Munro <thomas.mu...@enterprisedb.com> wrote: > On Sun, Mar 18, 2018 at 7:33 AM, Andres Freund <and...@anarazel.de> wrote: >> On 2018-03-17 14:20:26 -0400, Tom Lane wrote: >>> It might be worth studying the icc manual to see if it has an >>> equivalent of -fwrapv. >> >> Yes. >> >> A *quick* look through https://software.intel.com/en-us/node/522795 >> unfortunately didn't show anything. > > Apparently it does support -fno-strict-overflow. Is that useful here?
Hmm. This was already discussed here: https://www.postgresql.org/message-id/51016409.2020808%40gmail.com Noah seemed to be at least slightly in favour of considering turning it on despite doubt about its precise meaning, but also pointed out that even -fwrapv doesn't mean exactly the same thing in GCC and Clang. Curiously -fno-strict-overflow doesn't seem to appear in the documentation that Andres posted (well I couldn't find it quickly, anyway), but we can see that it exists from this interaction between Xi Wang and Intel compiler engineering: https://software.intel.com/en-us/forums/intel-c-compiler/topic/358200 And we can see a reference here: https://www.spec.org/cpu2017/flags/Intel-ic18.0-official-linux64.html -- Thomas Munro http://www.enterprisedb.com
