Re: Configure options for faster Jenkins builds

On Monday 14 of October 2019, Stephan Bergmann wrote:
> On 13/10/2019 21:15, Luboš Luňák wrote:
> >   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.
>
> Was the backtrace printed by gdb inspecting the core file, or was it
> printed from within the implementation of abort(2) in glibc?

 It was backtrace().

> For the tests to print gdb-generated backtraces on Linux, core files
> must be enabled (`ulimit -c unlimited`) and be stored as files named
> core* in cwd (see /proc/sys/kernel/core_pattern).  When those conditions
> are not met anyway for the relevant Gerrit/Jenkins builds,
> --enable-symbols likely doesn't give any benefit.

 I see. Both Linux Jenkins builds use that and print the backtrace using gdb. 
Windows and Mac on the other hand do not print any backtrace at all, so those 
either should get fix if possible and wanted, or there the build could be 
sped up this way (and they are usually the bottlenecks, right?).

-- 
 Luboš Luňák
 l.lunak@collabora.com