Recommended compiler version and flags for Linux x86_64

Hi,

I'm currently building and testing MonetDB on CentOS7, x86_64.

I was wondering about the recommended compiler version and compiler flags.

So far I'm using gcc 9 and specifically enabled SSE3 extensions (though I did not notice any performance gain).

Here's my cmake command cmake3 -DCMAKE_C_FLAGS="pthread -msse3 -O -Wall" -DCMAKE_INSTALL_PREFIX=../install ../MonetDB

Is there a list of recommended compiler flags?

Kind regards, Daniel