I wanted to see if /bin/dash was really that much faster (*), and found several problems. Some of them I can send patches for; some are in libtool which should really ditch its poor-man echo replacement; one is worth discussing here. The problem is that /bin/dash did not pass the "suggested" tests: it does not support $LINENO and AS_VAR_APPEND test. Now: 1) ditching $LINENO may be a little too heavy-weight, also because the replacement does not work for config.status (the parent script replaced $LINENO throughout, even in the generated scripts). By the way, this means that we can remove _AS_LINENO_PREPARE from _AS_PREPARE: since _AS_PREPARE has invoked AS_PREPARE and required _AS_LINENO_PREPARE in the parent, we know that there will be no $LINENO in the child script unless $LINENO works. We can then beg the dash developers to implement $LINENO. 2) The AS_VAR_APPEND technique, right now, does not give any speedup in Autoconf-generated scripts, as far as I could read. Nevertheless, we are rejecting all shells that do not support +=. This, unlike LINENO, is a pity, because it means that for everybody who's not using bash or zsh, but has it installed, the scripts will rerun in bash or zsh. This means in turn that we get much less coverage of shells in the wild. So, what about disabling the _AS_VAR_APPEND_WORKS test until it gives substantial performance improvements? Paolo (*) it is somewhat faster, but not that much: dash: real 0m41.898s user 0m22.629s sys 0m15.605s bash: real 0m46.232s user 0m23.905s sys 0m17.537s _______________________________________________ Autoconf mailing list Autoconf@xxxxxxx http://lists.gnu.org/mailman/listinfo/autoconf
