build_lin tries to rm stuff around root if builds fail

[leshy]

if make fails, build/lin folder is never created and

cd build/lin

fails, but

cd ../..

passes.
it will try to zip your whole hard drive, which is fine, but after it will run

ls | grep -v '\.zip$' | xargs rm

which will remove files in its current dir. this is most dangerous when it passes through your home folder, it ends at /

rm: cannot remove 'bin': Permission denied                               
rm: cannot remove 'boot': Is a directory                              
rm: cannot remove 'dev': Is a directory        
rm: cannot remove 'etc': Is a directory                                                                           
rm: cannot remove 'home': Is a directory        
rm: cannot remove 'lib': Permission denied        
rm: cannot remove 'lost+found': Is a directory                
rm: cannot remove 'mnt': Is a directory         
rm: cannot remove 'opt': Is a directory                       
rm: cannot remove 'proc': Is a directory                                                                                                                                             
rm: cannot remove 'root': Is a directory                                                                                                                                                                                                                       
rm: cannot remove 'sbin': Permission denied                                                                                                                                                                                                                             
rm: cannot remove 'srv': Is a directory                                                                                                                                     
rm: cannot remove 'sys': Is a directory                                                                                                                                
rm: cannot remove 'tmp': Is a directory                                                                                                                                              
rm: cannot remove 'usr': Is a directory                                                                                                                       
rm: cannot remove 'var': Is a directory                                                                                                                     

[rpasichnyk]

Add
set -e
in the beginning of the build script

[vedderb]

set -e is added, hopefully that solves the problem.