On Thu, Dec 15, 2016 at 12:57 PM, Diego Biurrun <[email protected]> wrote: > On Thu, Dec 15, 2016 at 08:43:16AM +0100, Steve Lhomme wrote: >> On Wed, Dec 14, 2016 at 5:12 PM, Diego Biurrun <[email protected]> wrote: >> > On Wed, Dec 14, 2016 at 04:46:54PM +0100, Steve Lhomme wrote: >> >> From: Steve Lhomme <[email protected]> >> >> >> >> Without any optimization flags, MSVC does no dead code elimination (DCE) >> >> at >> >> all, even for the most trivial cases. DCE is a prerequisite for building >> >> libav >> >> correctly, otherwise there are undefined references to functions for other >> >> architectures and disabled components. >> >> >> >> -Os -Og is the minimal optimization flags for MSVC that does include DCE. >> >> It >> > >> > -Os -Og are .. that do .. >> >> I would say "the setting '-Os -Og' is". One could say "the flags '-Os -Og' >> are". > > Now that you added the quotes it is indeed right ;-p > >> >> warns that -Og will be removed but it doesn't work without. -O1 includes >> >> these >> >> flags and some other ones not necessary to link properly. >> > >> > What does "warn" mean? And is this combination really preferable to plain >> > -O1? >> >> Every C file compiled warns that Og is deprecated and may be removed >> soon. I prefer it to -O1 because it involves less optimizations, which >> is the goal of --disable-optimizations. O1 sets "-Og -Os -Oy -Ob2 -Gs >> -GF -Gy". > > Adding a warning for every file is not something we should do lightly. > Warnings are valuable and they become complete noise when the silly > warnings drown out the real ones. > > If Og is deprecated, what is its replacement? >
Microsoft is discontinuing the fine-grained optimization options and recommends to just stick to O1 and O2. - Hendrik _______________________________________________ libav-devel mailing list [email protected] https://lists.libav.org/mailman/listinfo/libav-devel
