On 30/09/2020 19:04, Zidenberg, Tsahi wrote:
> Ubuntu 20.04 even turned it off by default for gcc-10, which seems
> like a compatibility step with the main gcc-9 compiler.
Ok, I definitely don't want to override that decision.
>> I'm marking this as Rejected in the commitfest. But thanks for the
>> benchmarking, that is valuable information nevertheless.
>
> Could additional data change your mind?
I doubt it. IMO we shouldn't second-guess decisions made by compiler and
distribution vendors, and more performance data won't change that
principle. For comparison, we also don't set -O or -funroll-loops or any
other flags to enable/disable specific optimizations. (Except for a few
specific source files, like checksum.c, but those are exceptions the rule.)
If some other committer thinks differently, I won't object, but I'm not
going to commit this. Maybe you should speak to the distribution vendors
or the folk packaging PostgreSQL for those distributions, instead.
- Heikki
