[Ecls-list] clang compiler is slower than gss

[Anton Vodonosov]

Hi.

There was a discussion in cl-test-grid google group
(https://groups.google.com/forum/#!topic/cl-test-grid/6uqyuj6Jy-0)
about timeouts when running ECL tests on MacOSX Maverick,
which uses clang as the C compiler.

What might be interesting to ECL users is that
clang takes much longer to compile some of the C
code generated by ECL from Lisp code.

For example to recompile jwacs system I use
the following command on linux:

  rm -rf ~/.cache/common-lisp/   
  time ~/lisps/ecl-bin-git/bin/ecl -norc -eval '(require :cmp)' -load ~/quicklisp/setup.lisp -eval '(ql:quickload :jwacs)' -eval '(quit)' 

The results (linux + gcc): 

  real    7m26.532s 
  user    7m22.304s 
  sys     0m2.880s 


The results for MacOSX Maverick + clang:

  real    68m9.271s
  user    58m58.793s
  sys     2m40.499s

For cl-test-grid this lead to improvement of handling timeouts
of tested lisp processes on unix. Namely, when timeout is detected
tg-agent kills not only ECL, but whole process tree,
including the C processes started by ECL

Best regards,
- Anton