Re: LuaHBTeX from TL26 is significantly slower than in TL25

Hi Petr - thanks much for the report. 

    It seems that the problem is related to settings of compilation
    environment when a binary is built. 

Indeed so. It seems I introduced a bug in the ./Build script with the
effect of overriding Autoconf's normal computation of CFLAGS as 
-g -O2. Hence the builds, including x86_64-linux, were happening with
neither debugging (doesn't matter) nor optimization (does matter).

After I see a successful build with optimization (there's an independent
breakage of github on *-linux right now), I'll add a check to the github
build script that optimization was used, since that's always intended
for the github builds.

Very glad you noticed and reported. --thanks, karl.

P.S. I shudder to think how long the armhf and aarch builds will take
now.