On Thu, Jan 25, 2018 at 2:53 PM, Sérgio Basto <sergio@serjux.com> wrote:

Hi,
Question about gcc cflag ffast-math .
Should I enable cflag ffast-math on opencv build explicitly
( -DENABLE_FAST_MATH=ON ) ? and I keep disable cflag ffast-math in mlt
build [1] ?

I have no meaningful comment on compiling with -ffast-math, but you absolutely should not *link* with -ffast-math. See:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=55522

and

https://bugzilla.redhat.com/show_bug.cgi?id=1248744

Also, if any toolchain people are listening, maybe you could consider fixing the GCC bug? It should be easy, since it mostly consists of option tweaking.