Re: sort dynamic linking overhead

[Paul Eggert]

Thanks for the patch. I was hoping that we didn't need to worry about 
older platforms needing -ldl. Oh well.

The patch causes 'configure' to search for dlopen even when there's no 
crypto library. 'configure' could instead use AC_SEARCH_LIBS only if the 
AC_LINK_IFELSE fails (or simply put AC_LINK_ELSE in an 'for LIB_DL in "" 
-ldl' loop). But perhaps it's better to leave things be, in case we ever 
need dlopen for something else.

Also, if I understand things correctly, with this patch it's 
theoretically possible to pass -ldl to gcc even when 'sort' doesn't do 
dynamic linking, and we could complicate configure.ac further to omit 
-ldl in that case. But I doubt whether it's worth worrying about this.