will cause kpathsea to consider all subdirectories recursively at that point
in the path. Normally double-slashes and trailing slashes will not be present
in VARBASE, etc. But if they are there the resulting behaviour is so
unexpected, expensive, and difficult to diagnose that it is worth going to
extra effort to clean them out here.
The problem is easy to hit when using Pkgsrc installing under $HOME on a
system where the user's home directories contain a trailing slash.
Somewhat reluctantly bump PKGREVISION.
This changes the buildlink3.mk files to use an include guard for the
recursive include. The use of BUILDLINK_DEPTH, BUILDLINK_DEPENDS,
BUILDLINK_PACKAGES and BUILDLINK_ORDER is handled by a single new
variable BUILDLINK_TREE. Each buildlink3.mk file adds a pair of
enter/exit marker, which can be used to reconstruct the tree and
to determine first level includes. Avoiding := for large variables
(BUILDLINK_ORDER) speeds up parse time as += has linear complexity.
The include guard reduces system time by avoiding reading files over and
over again. For complex packages this reduces both %user and %sys time to
half of the former time.
Kpathsea is a library to do path searching. It is used in the Web2C
implementation of TeX and friends. The library's fundamental purpose
is to return a filename from a list of directories specified by the
user, similar to what shells do when looking up program names to
execute.
