I have a small Jamfile that sits in libs/regex and contains nothing except:

subproject libs/regex ;

subinclude libs/regex/example ;
subinclude libs/regex/test ;

However when I try and build this Jamfile the regex lib itself fails to
build (none of the <template> options in the libs/regex/build/Jamfile get
applied, so the compiler can't find the include files among other things).
Building from libs/regex/test or libs/regex/example works just fine however.
This is a new issue - it was all working just fine prior to some recent
build system changes.

John.