Configure options for faster Jenkins builds

[Luboš Luňák]

 Hello,

 is there any specific reason why the Jenkins builds do not 
use --disable-dependency-tracking and/or --disable-symbols?

 I've noticed in the logs that Jenkins builds do 'make clean' at the start, so 
they are one-time builds and thus do not need dependency tracking, so they 
just work just fine with --disable-dependency-tracking (and apparently they 
do, https://gerrit.libreoffice.org/#/c/80730). I have not tried with a 
complete build, but just with the relatively small 'make starmath.build' 
adding 'nodep=TRUE' saves about 10% of build time here (on Windows, where it 
probably makes the biggest difference).

 And --disable-symbols is basically like adding -g0 to CXXFLAGS. Most setups 
build with --enable-dbgutils to build with full debug builds, but in fact 
generating debug symbols mostly seems like a waste for Jenkins builds. Is 
that actually used for something? I know unittests on Linux print backtraces 
on crashes/aborts, but I've just tried adding abort() in a random unittest 
and the backtrace is not very useful, because it doesn't use debug symbols 
anyway. And with just 'make starmath.build' adding 'ENABLE_SYMBOLS_FOR=' 
saves again about 10% of build time here.

 Does somebody know a good reason why I shouldn't push these changes?

-- 
 Luboš Luňák
 l.lunak at collabora.com