These allow some very useful magic in the makefiles.
The comment in var.c describing their behaviour is mostly lifted
from ODE make, but the implementation of the modifiers themselves
is quite different (much simpler) due to divergence of our code base.
Firstly, we ignore getenv("PWD") if MAKEOBJDIRPREFIX is set so that we always
get the same value for .CURDIR regardless of how make was invoked.
Second, when executing a command we check if it is ${.MAKE} or ${.MAKE:T}
without a preceeding chdir, if so we insert a chdir(${.CURDIR}) so that
the Makefile will be found by the child make. Note that this behaviour is
dissabled if MAKEOBJDIRPREFIX is not set or if NOCHECKMAKECHDIR is set.
See the comments in main.c for more detail.
With these two changes, one can successfully build usr/src using MAKEOBJDIRPREFIX
allowing the src to be mounted from a CD-ROM.
someone wants to do freaky stuff with $MAKEOBJDIR.
Initialize the Var system and set .CURDIR, MACHINE and MACHINE_ARCH
before chdir_verify_path() is called.
list of target nodes returned by Make_ExpandUse(). We have to search the
cohorts explicitly while iterating through the tree. So, tweak CompatMake()
to do this.
can (i.e., everything except environment variables, which aren't
stored in hash tables).
While we're here, inline the body of VarDelete into Var_Delete since
it's the only caller and it's just simpler that way when v->name can
share storage with the hash entry and may not need to be freed
separately.
Speeds up the infamous libc build benchhmark maybe 1% on PIII, 4% on
alpha pc164
Suggested by Perry Metzger.
Build a list of `cohorts' as before, but do *not* link each one into all the
parent nodes; instead, copy the `cohort' lists into the stream of targets to
be built inside Make_ExpandUse(). Also do the attribute propagation as a
separate pass after parsing.
This eliminates several O(n^2) algorithms.
passing in the LstNode of the child being inspected. Shaves off another few %,
particularly when there are long child lists containing $ expansions (e.g. in
libc).
in the presence of .PATH directives by specifying:
.PATH: .DOTLAST
This will be used to fixup the build system to work with both crypto-us
and crypto-intl sub-trees.
Make(1) changes by Christos Zoulas, after much badgering by me :-)
sjg