We want to use -flto=auto in Arch Linux to speed up building, but we
can't hardcode it in buildenv/lto.sh because other downstreams might
have clang < 13.0.0 which did not recognize -flto=auto as equivalent
to -flto=full.
Introducing an LTOFLAGS variable to makepkg.conf seems the way to go.
Signed-off-by: Allan McRae <allan@archlinux.org>
GCC automatically detects when it is linking LTO objects, but clang does
not. Add -flto to LDFLAGS to make this work for clang too.
Signed-off-by: Allan McRae <allan@archlinux.org>
Add the 'lto' option to enable building with link time optimization
by adding '-flto' to both CFLAGS and CXXFLAGS. The 'lto' option can
be specificed both in the PKGBUILD or by setting the default in
makepkg.conf.
Signed-off-by: Allan McRae <allan@archlinux.org>
