Simply and speed up buildlink3.mk files and processing.

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.

32 files changed, 192 insertions, 416 deletions

diff --git a/math/R/buildlink3.mk b/math/R/buildlink3.mk
index 4c63eb8dc61..c8bdf4c4ff9 100644
--- a/math/R/buildlink3.mk
+++ b/math/R/buildlink3.mk
@@ -1,20 +1,13 @@
-# $NetBSD: buildlink3.mk,v 1.7 2006/07/08 23:10:58 jlam Exp $
+# $NetBSD: buildlink3.mk,v 1.8 2009/03/20 19:24:56 joerg Exp $
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH}+
-R_BUILDLINK3_MK:=	${R_BUILDLINK3_MK}+
+BUILDLINK_TREE+=	R
 
-.if !empty(BUILDLINK_DEPTH:M+)
-BUILDLINK_DEPENDS+=	R
-.endif
+.if !defined(R_BUILDLINK3_MK)
+R_BUILDLINK3_MK:=
 
-BUILDLINK_PACKAGES:=	${BUILDLINK_PACKAGES:NR}
-BUILDLINK_PACKAGES+=	R
-BUILDLINK_ORDER:=	${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}R
-
-.if !empty(R_BUILDLINK3_MK:M+)
 BUILDLINK_API_DEPENDS.R+=	R>=1.7.0
 BUILDLINK_ABI_DEPENDS.R?=	R>=2.2.1nb2
 BUILDLINK_PKGSRCDIR.R?=	../../math/R
-.endif	# R_BUILDLINK3_MK
+.endif # R_BUILDLINK3_MK
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH:S/+$//}
+BUILDLINK_TREE+=	-R
diff --git a/math/blas/buildlink3.mk b/math/blas/buildlink3.mk
index a8050cd8585..80124c99072 100644
--- a/math/blas/buildlink3.mk
+++ b/math/blas/buildlink3.mk
@@ -1,20 +1,13 @@
-# $NetBSD: buildlink3.mk,v 1.7 2006/07/08 23:10:59 jlam Exp $
+# $NetBSD: buildlink3.mk,v 1.8 2009/03/20 19:24:56 joerg Exp $
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH}+
-BLAS_BUILDLINK3_MK:=	${BLAS_BUILDLINK3_MK}+
+BUILDLINK_TREE+=	blas
 
-.if !empty(BUILDLINK_DEPTH:M+)
-BUILDLINK_DEPENDS+=	blas
-.endif
+.if !defined(BLAS_BUILDLINK3_MK)
+BLAS_BUILDLINK3_MK:=
 
-BUILDLINK_PACKAGES:=	${BUILDLINK_PACKAGES:Nblas}
-BUILDLINK_PACKAGES+=	blas
-BUILDLINK_ORDER:=	${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}blas
-
-.if !empty(BLAS_BUILDLINK3_MK:M+)
 BUILDLINK_API_DEPENDS.blas+=	blas>=1.0nb2
 BUILDLINK_ABI_DEPENDS.blas+=	blas>=1.0nb3
 BUILDLINK_PKGSRCDIR.blas?=	../../math/blas
-.endif	# BLAS_BUILDLINK3_MK
+.endif # BLAS_BUILDLINK3_MK
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH:S/+$//}
+BUILDLINK_TREE+=	-blas
diff --git a/math/cln/buildlink3.mk b/math/cln/buildlink3.mk
index 711e6587202..5d596386383 100644
--- a/math/cln/buildlink3.mk
+++ b/math/cln/buildlink3.mk
@@ -1,20 +1,13 @@
-# $NetBSD: buildlink3.mk,v 1.8 2006/07/08 23:10:59 jlam Exp $
+# $NetBSD: buildlink3.mk,v 1.9 2009/03/20 19:24:56 joerg Exp $
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH}+
-CLN_BUILDLINK3_MK:=	${CLN_BUILDLINK3_MK}+
+BUILDLINK_TREE+=	cln
 
-.if !empty(BUILDLINK_DEPTH:M+)
-BUILDLINK_DEPENDS+=	cln
-.endif
+.if !defined(CLN_BUILDLINK3_MK)
+CLN_BUILDLINK3_MK:=
 
-BUILDLINK_PACKAGES:=	${BUILDLINK_PACKAGES:Ncln}
-BUILDLINK_PACKAGES+=	cln
-BUILDLINK_ORDER:=	${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}cln
-
-.if !empty(CLN_BUILDLINK3_MK:M+)
 BUILDLINK_API_DEPENDS.cln+=		cln>=1.1.6
 BUILDLINK_ABI_DEPENDS.cln+=	cln>=1.1.9nb1
 BUILDLINK_PKGSRCDIR.cln?=	../../math/cln
-.endif	# CLN_BUILDLINK3_MK
+.endif # CLN_BUILDLINK3_MK
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH:S/+$//}
+BUILDLINK_TREE+=	-cln
diff --git a/math/djbfft/buildlink3.mk b/math/djbfft/buildlink3.mk
index 8f45f62b3f5..a4b05080a66 100644
--- a/math/djbfft/buildlink3.mk
+++ b/math/djbfft/buildlink3.mk
@@ -1,20 +1,13 @@
-# $NetBSD: buildlink3.mk,v 1.5 2006/07/08 23:10:59 jlam Exp $
+# $NetBSD: buildlink3.mk,v 1.6 2009/03/20 19:24:56 joerg Exp $
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH}+
-DJBFFT_BUILDLINK3_MK:=	${DJBFFT_BUILDLINK3_MK}+
+BUILDLINK_TREE+=	djbfft
 
-.if !empty(BUILDLINK_DEPTH:M+)
-BUILDLINK_DEPENDS+=	djbfft
-.endif
+.if !defined(DJBFFT_BUILDLINK3_MK)
+DJBFFT_BUILDLINK3_MK:=
 
-BUILDLINK_PACKAGES:=	${BUILDLINK_PACKAGES:Ndjbfft}
-BUILDLINK_PACKAGES+=	djbfft
-BUILDLINK_ORDER:=	${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}djbfft
-
-.if !empty(DJBFFT_BUILDLINK3_MK:M+)
 BUILDLINK_API_DEPENDS.djbfft+=	djbfft>=0.76
 BUILDLINK_PKGSRCDIR.djbfft?=	../../math/djbfft
 BUILDLINK_DEPMETHOD.djbfft?=	build
-.endif	# DJBFFT_BUILDLINK3_MK
+.endif # DJBFFT_BUILDLINK3_MK
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH:S/+$//}
+BUILDLINK_TREE+=	-djbfft
diff --git a/math/eigen2/buildlink3.mk b/math/eigen2/buildlink3.mk
index abe58f29fbb..0c95fa375dc 100644
--- a/math/eigen2/buildlink3.mk
+++ b/math/eigen2/buildlink3.mk
@@ -1,20 +1,13 @@
-# $NetBSD: buildlink3.mk,v 1.1.1.1 2009/01/10 01:02:47 markd Exp $
+# $NetBSD: buildlink3.mk,v 1.2 2009/03/20 19:24:56 joerg Exp $
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH}+
-EIGEN_BUILDLINK3_MK:=	${EIGEN_BUILDLINK3_MK}+
+BUILDLINK_TREE+=	eigen
 
-.if ${BUILDLINK_DEPTH} == "+"
-BUILDLINK_DEPENDS+=	eigen
-.endif
+.if !defined(EIGEN_BUILDLINK3_MK)
+EIGEN_BUILDLINK3_MK:=
 
-BUILDLINK_PACKAGES:=	${BUILDLINK_PACKAGES:Neigen}
-BUILDLINK_PACKAGES+=	eigen
-BUILDLINK_ORDER:=	${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}eigen
-
-.if ${EIGEN_BUILDLINK3_MK} == "+"
 BUILDLINK_API_DEPENDS.eigen+=	eigen>=2.0beta3
 BUILDLINK_PKGSRCDIR.eigen?=	../../math/eigen2
 BUILDLINK_DEPMETHOD.eigen?=	build
-.endif	# EIGEN_BUILDLINK3_MK
+.endif # EIGEN_BUILDLINK3_MK
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH:S/+$//}
+BUILDLINK_TREE+=	-eigen
diff --git a/math/fftw/buildlink3.mk b/math/fftw/buildlink3.mk
index 354e59a612f..da4835a80bc 100644
--- a/math/fftw/buildlink3.mk
+++ b/math/fftw/buildlink3.mk
@@ -1,20 +1,13 @@
-# $NetBSD: buildlink3.mk,v 1.7 2006/07/08 23:10:59 jlam Exp $
+# $NetBSD: buildlink3.mk,v 1.8 2009/03/20 19:24:56 joerg Exp $
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH}+
-FFTW_BUILDLINK3_MK:=	${FFTW_BUILDLINK3_MK}+
+BUILDLINK_TREE+=	fftw
 
-.if !empty(BUILDLINK_DEPTH:M+)
-BUILDLINK_DEPENDS+=	fftw
-.endif
+.if !defined(FFTW_BUILDLINK3_MK)
+FFTW_BUILDLINK3_MK:=
 
-BUILDLINK_PACKAGES:=	${BUILDLINK_PACKAGES:Nfftw}
-BUILDLINK_PACKAGES+=	fftw
-BUILDLINK_ORDER:=	${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}fftw
-
-.if !empty(FFTW_BUILDLINK3_MK:M+)
 BUILDLINK_API_DEPENDS.fftw+=	fftw>=3.0
 BUILDLINK_ABI_DEPENDS.fftw+=	fftw>=3.1nb1
 BUILDLINK_PKGSRCDIR.fftw?=	../../math/fftw
-.endif	# FFTW_BUILDLINK3_MK
+.endif # FFTW_BUILDLINK3_MK
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH:S/+$//}
+BUILDLINK_TREE+=	-fftw
diff --git a/math/fftw2/buildlink3.mk b/math/fftw2/buildlink3.mk
index 1324bd49e05..74979071ba2 100644
--- a/math/fftw2/buildlink3.mk
+++ b/math/fftw2/buildlink3.mk
@@ -1,20 +1,13 @@
-# $NetBSD: buildlink3.mk,v 1.7 2006/07/08 23:10:59 jlam Exp $
+# $NetBSD: buildlink3.mk,v 1.8 2009/03/20 19:24:56 joerg Exp $
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH}+
-FFTW2_BUILDLINK3_MK:=	${FFTW2_BUILDLINK3_MK}+
+BUILDLINK_TREE+=	fftw2
 
-.if !empty(BUILDLINK_DEPTH:M+)
-BUILDLINK_DEPENDS+=	fftw2
-.endif
+.if !defined(FFTW2_BUILDLINK3_MK)
+FFTW2_BUILDLINK3_MK:=
 
-BUILDLINK_PACKAGES:=	${BUILDLINK_PACKAGES:Nfftw2}
-BUILDLINK_PACKAGES+=	fftw2
-BUILDLINK_ORDER:=	${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}fftw2
-
-.if !empty(FFTW2_BUILDLINK3_MK:M+)
 BUILDLINK_API_DEPENDS.fftw2+=	fftw2>=2.1.3
 BUILDLINK_ABI_DEPENDS.fftw2?=	fftw2>=2.1.5nb2
 BUILDLINK_PKGSRCDIR.fftw2?=	../../math/fftw2
-.endif	# FFTW2_BUILDLINK3_MK
+.endif # FFTW2_BUILDLINK3_MK
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH:S/+$//}
+BUILDLINK_TREE+=	-fftw2
diff --git a/math/fftwf/buildlink3.mk b/math/fftwf/buildlink3.mk
index 21d8e9c70c3..c18b6c81c87 100644
--- a/math/fftwf/buildlink3.mk
+++ b/math/fftwf/buildlink3.mk
@@ -1,22 +1,15 @@
-# $NetBSD: buildlink3.mk,v 1.6 2006/07/08 23:10:59 jlam Exp $
+# $NetBSD: buildlink3.mk,v 1.7 2009/03/20 19:24:56 joerg Exp $
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH}+
-FFTWF_BUILDLINK3_MK:=	${FFTWF_BUILDLINK3_MK}+
+BUILDLINK_TREE+=	fftwf
 
-.if !empty(BUILDLINK_DEPTH:M+)
-BUILDLINK_DEPENDS+=	fftwf
-.endif
+.if !defined(FFTWF_BUILDLINK3_MK)
+FFTWF_BUILDLINK3_MK:=
 
-BUILDLINK_PACKAGES:=	${BUILDLINK_PACKAGES:Nfftwf}
-BUILDLINK_PACKAGES+=	fftwf
-BUILDLINK_ORDER:=	${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}fftwf
-
-.if !empty(FFTWF_BUILDLINK3_MK:M+)
 BUILDLINK_API_DEPENDS.fftwf+=	fftwf>=3.0
 BUILDLINK_ABI_DEPENDS.fftwf+=	fftwf>=3.0.1nb1
 BUILDLINK_PKGSRCDIR.fftwf?=	../../math/fftwf
-.endif	# FFTWF_BUILDLINK3_MK
 
 .include "../../math/fftw/buildlink3.mk"
+.endif # FFTWF_BUILDLINK3_MK
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH:S/+$//}
+BUILDLINK_TREE+=	-fftwf
diff --git a/math/glpk/buildlink3.mk b/math/glpk/buildlink3.mk
index 35c0a5db0da..3034cc2b040 100644
--- a/math/glpk/buildlink3.mk
+++ b/math/glpk/buildlink3.mk
@@ -1,22 +1,15 @@
-# $NetBSD: buildlink3.mk,v 1.8 2007/01/04 22:38:49 adam Exp $
+# $NetBSD: buildlink3.mk,v 1.9 2009/03/20 19:24:57 joerg Exp $
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH}+
-GLPK_BUILDLINK3_MK:=	${GLPK_BUILDLINK3_MK}+
+BUILDLINK_TREE+=	glpk
 
-.if !empty(BUILDLINK_DEPTH:M+)
-BUILDLINK_DEPENDS+=	glpk
-.endif
+.if !defined(GLPK_BUILDLINK3_MK)
+GLPK_BUILDLINK3_MK:=
 
-BUILDLINK_PACKAGES:=	${BUILDLINK_PACKAGES:Nglpk}
-BUILDLINK_PACKAGES+=	glpk
-BUILDLINK_ORDER:=	${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}glpk
-
-.if !empty(GLPK_BUILDLINK3_MK:M+)
 BUILDLINK_API_DEPENDS.glpk+=	glpk>=4.8nb1
 BUILDLINK_ABI_DEPENDS.glpk+=	glpk>=4.9nb1
 BUILDLINK_PKGSRCDIR.glpk?=	../../math/glpk
-.endif	# GLPK_BUILDLINK3_MK
 
 .include "../../devel/gmp/buildlink3.mk"
+.endif # GLPK_BUILDLINK3_MK
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH:S/+$//}
+BUILDLINK_TREE+=	-glpk
diff --git a/math/gsl/buildlink3.mk b/math/gsl/buildlink3.mk
index 5da3d236a3a..bfa24953ada 100644
--- a/math/gsl/buildlink3.mk
+++ b/math/gsl/buildlink3.mk
@@ -1,20 +1,13 @@
-# $NetBSD: buildlink3.mk,v 1.7 2006/07/08 23:10:59 jlam Exp $
+# $NetBSD: buildlink3.mk,v 1.8 2009/03/20 19:24:57 joerg Exp $
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH}+
-GSL_BUILDLINK3_MK:=	${GSL_BUILDLINK3_MK}+
+BUILDLINK_TREE+=	gsl
 
-.if !empty(BUILDLINK_DEPTH:M+)
-BUILDLINK_DEPENDS+=	gsl
-.endif
+.if !defined(GSL_BUILDLINK3_MK)
+GSL_BUILDLINK3_MK:=
 
-BUILDLINK_PACKAGES:=	${BUILDLINK_PACKAGES:Ngsl}
-BUILDLINK_PACKAGES+=	gsl
-BUILDLINK_ORDER:=	${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}gsl
-
-.if !empty(GSL_BUILDLINK3_MK:M+)
 BUILDLINK_API_DEPENDS.gsl+=		gsl>=1.4
 BUILDLINK_ABI_DEPENDS.gsl+=	gsl>=1.5nb1
 BUILDLINK_PKGSRCDIR.gsl?=	../../math/gsl
-.endif	# GSL_BUILDLINK3_MK
+.endif # GSL_BUILDLINK3_MK
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH:S/+$//}
+BUILDLINK_TREE+=	-gsl
diff --git a/math/lapack/buildlink3.mk b/math/lapack/buildlink3.mk
index bc804754892..1eb9492d3d5 100644
--- a/math/lapack/buildlink3.mk
+++ b/math/lapack/buildlink3.mk
@@ -1,20 +1,13 @@
-# $NetBSD: buildlink3.mk,v 1.8 2007/12/10 17:50:31 adam Exp $
+# $NetBSD: buildlink3.mk,v 1.9 2009/03/20 19:24:57 joerg Exp $
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH}+
-LAPACK_BUILDLINK3_MK:=	${LAPACK_BUILDLINK3_MK}+
+BUILDLINK_TREE+=	lapack
 
-.if !empty(BUILDLINK_DEPTH:M+)
-BUILDLINK_DEPENDS+=	lapack
-.endif
+.if !defined(LAPACK_BUILDLINK3_MK)
+LAPACK_BUILDLINK3_MK:=
 
-BUILDLINK_PACKAGES:=	${BUILDLINK_PACKAGES:Nlapack}
-BUILDLINK_PACKAGES+=	lapack
-BUILDLINK_ORDER:=	${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}lapack
-
-.if !empty(LAPACK_BUILDLINK3_MK:M+)
 BUILDLINK_API_DEPENDS.lapack+=	lapack>=3.1.1
 BUILDLINK_ABI_DEPENDS.lapack+=	lapack>=3.1.1
 BUILDLINK_PKGSRCDIR.lapack?=	../../math/lapack
-.endif	# LAPACK_BUILDLINK3_MK
+.endif # LAPACK_BUILDLINK3_MK
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH:S/+$//}
+BUILDLINK_TREE+=	-lapack
diff --git a/math/libffm/buildlink3.mk b/math/libffm/buildlink3.mk
index 324ffb514e2..008d0d11b96 100644
--- a/math/libffm/buildlink3.mk
+++ b/math/libffm/buildlink3.mk
@@ -1,20 +1,13 @@
-# $NetBSD: buildlink3.mk,v 1.7 2006/07/08 23:10:59 jlam Exp $
+# $NetBSD: buildlink3.mk,v 1.8 2009/03/20 19:24:57 joerg Exp $
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH}+
-LIBFFM_BUILDLINK3_MK:=	${LIBFFM_BUILDLINK3_MK}+
+BUILDLINK_TREE+=	libffm
 
-.if !empty(BUILDLINK_DEPTH:M+)
-BUILDLINK_DEPENDS+=	libffm
-.endif
+.if !defined(LIBFFM_BUILDLINK3_MK)
+LIBFFM_BUILDLINK3_MK:=
 
-BUILDLINK_PACKAGES:=	${BUILDLINK_PACKAGES:Nlibffm}
-BUILDLINK_PACKAGES+=	libffm
-BUILDLINK_ORDER:=	${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}libffm
-
-.if !empty(LIBFFM_BUILDLINK3_MK:M+)
 BUILDLINK_API_DEPENDS.libffm+=	libffm>=0.28
 BUILDLINK_ABI_DEPENDS.libffm?=	libffm>=0.28nb1
 BUILDLINK_PKGSRCDIR.libffm?=	../../math/libffm
-.endif	# LIBFFM_BUILDLINK3_MK
+.endif # LIBFFM_BUILDLINK3_MK
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH:S/+$//}
+BUILDLINK_TREE+=	-libffm
diff --git a/math/libmatheval/buildlink3.mk b/math/libmatheval/buildlink3.mk
index d04c45054bf..69e7364ea70 100644
--- a/math/libmatheval/buildlink3.mk
+++ b/math/libmatheval/buildlink3.mk
@@ -1,23 +1,16 @@
-# $NetBSD: buildlink3.mk,v 1.8 2006/07/08 23:10:59 jlam Exp $
+# $NetBSD: buildlink3.mk,v 1.9 2009/03/20 19:24:57 joerg Exp $
 
-BUILDLINK_DEPTH:=		${BUILDLINK_DEPTH}+
-LIBMATHEVAL_BUILDLINK3_MK:=	${LIBMATHEVAL_BUILDLINK3_MK}+
+BUILDLINK_TREE+=	libmatheval
 
-.if !empty(BUILDLINK_DEPTH:M+)
-BUILDLINK_DEPENDS+=	libmatheval
-.endif
+.if !defined(LIBMATHEVAL_BUILDLINK3_MK)
+LIBMATHEVAL_BUILDLINK3_MK:=
 
-BUILDLINK_PACKAGES:=	${BUILDLINK_PACKAGES:Nlibmatheval}
-BUILDLINK_PACKAGES+=	libmatheval
-BUILDLINK_ORDER:=	${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}libmatheval
-
-.if !empty(LIBMATHEVAL_BUILDLINK3_MK:M+)
 BUILDLINK_API_DEPENDS.libmatheval+=	libmatheval>=1.1.0
 BUILDLINK_ABI_DEPENDS.libmatheval+=	libmatheval>=1.1.1nb3
 BUILDLINK_PKGSRCDIR.libmatheval?=	../../math/libmatheval
-.endif	# LIBMATHEVAL_BUILDLINK3_MK
 
 .include "../../devel/flex/buildlink3.mk"
 .include "../../lang/guile/buildlink3.mk"
+.endif # LIBMATHEVAL_BUILDLINK3_MK
 
-BUILDLINK_DEPTH:=		${BUILDLINK_DEPTH:S/+$//}
+BUILDLINK_TREE+=	-libmatheval
diff --git a/math/ltm/buildlink3.mk b/math/ltm/buildlink3.mk
index 69deca93cb0..74219529cc2 100644
--- a/math/ltm/buildlink3.mk
+++ b/math/ltm/buildlink3.mk
@@ -1,21 +1,14 @@
-# $NetBSD: buildlink3.mk,v 1.6 2006/07/08 23:10:59 jlam Exp $
+# $NetBSD: buildlink3.mk,v 1.7 2009/03/20 19:24:57 joerg Exp $
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH}+
-LTM_BUILDLINK3_MK:=	${LTM_BUILDLINK3_MK}+
+BUILDLINK_TREE+=	ltm
 
-.if !empty(BUILDLINK_DEPTH:M+)
-BUILDLINK_DEPENDS+=	ltm
-.endif
+.if !defined(LTM_BUILDLINK3_MK)
+LTM_BUILDLINK3_MK:=
 
-BUILDLINK_PACKAGES:=	${BUILDLINK_PACKAGES:Nltm}
-BUILDLINK_PACKAGES+=	ltm
-BUILDLINK_ORDER:=	${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}ltm
-
-.if !empty(LTM_BUILDLINK3_MK:M+)
 BUILDLINK_API_DEPENDS.ltm+=	ltm>=0.30
 BUILDLINK_ABI_DEPENDS.ltm?=	ltm>=0.30nb1
 BUILDLINK_PKGSRCDIR.ltm?=	../../math/ltm
 BUILDLINK_DEPMETHOD.ltm?=	build
-.endif	# LTM_BUILDLINK3_MK
+.endif # LTM_BUILDLINK3_MK
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH:S/+$//}
+BUILDLINK_TREE+=	-ltm
diff --git a/math/mpfr/buildlink3.mk b/math/mpfr/buildlink3.mk
index e384d422432..efdc0430ce0 100644
--- a/math/mpfr/buildlink3.mk
+++ b/math/mpfr/buildlink3.mk
@@ -1,21 +1,14 @@
-# $NetBSD: buildlink3.mk,v 1.6 2007/09/18 20:15:58 drochner Exp $
+# $NetBSD: buildlink3.mk,v 1.7 2009/03/20 19:24:57 joerg Exp $
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH}+
-MPFR_BUILDLINK3_MK:=	${MPFR_BUILDLINK3_MK}+
+BUILDLINK_TREE+=	mpfr
 
-.if !empty(BUILDLINK_DEPTH:M+)
-BUILDLINK_DEPENDS+=	mpfr
-.endif
+.if !defined(MPFR_BUILDLINK3_MK)
+MPFR_BUILDLINK3_MK:=
 
-BUILDLINK_PACKAGES:=	${BUILDLINK_PACKAGES:Nmpfr}
-BUILDLINK_PACKAGES+=	mpfr
-BUILDLINK_ORDER:=	${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}mpfr
-
-.if !empty(MPFR_BUILDLINK3_MK:M+)
 BUILDLINK_API_DEPENDS.mpfr+=	mpfr>=2.0.3
 BUILDLINK_PKGSRCDIR.mpfr?=	../../math/mpfr
-.endif	# MPFR_BUILDLINK3_MK
 
 .include "../../devel/gmp/buildlink3.mk"
+.endif # MPFR_BUILDLINK3_MK
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH:S/+$//}
+BUILDLINK_TREE+=	-mpfr
diff --git a/math/ntl/buildlink3.mk b/math/ntl/buildlink3.mk
index dfdb67a41b6..e7258e0144d 100644
--- a/math/ntl/buildlink3.mk
+++ b/math/ntl/buildlink3.mk
@@ -1,22 +1,15 @@
-# $NetBSD: buildlink3.mk,v 1.6 2006/07/08 23:10:59 jlam Exp $
+# $NetBSD: buildlink3.mk,v 1.7 2009/03/20 19:24:57 joerg Exp $
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH}+
-NTL_BUILDLINK3_MK:=	${NTL_BUILDLINK3_MK}+
+BUILDLINK_TREE+=	ntl
 
-.if !empty(BUILDLINK_DEPTH:M+)
-BUILDLINK_DEPENDS+=	ntl
-.endif
+.if !defined(NTL_BUILDLINK3_MK)
+NTL_BUILDLINK3_MK:=
 
-BUILDLINK_PACKAGES:=	${BUILDLINK_PACKAGES:Nntl}
-BUILDLINK_PACKAGES+=	ntl
-BUILDLINK_ORDER:=	${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}ntl
-
-.if !empty(NTL_BUILDLINK3_MK:M+)
 BUILDLINK_API_DEPENDS.ntl+=	ntl>=5.3.1
 BUILDLINK_ABI_DEPENDS.ntl+=	ntl>=5.3.1nb1
 BUILDLINK_PKGSRCDIR.ntl?=	../../math/ntl
-.endif	# NTL_BUILDLINK3_MK
 
 .include "../../devel/gmp/buildlink3.mk"
+.endif # NTL_BUILDLINK3_MK
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH:S/+$//}
+BUILDLINK_TREE+=	-ntl
diff --git a/math/octave-forge/buildlink3.mk b/math/octave-forge/buildlink3.mk
index 48523b55994..c669292c995 100644
--- a/math/octave-forge/buildlink3.mk
+++ b/math/octave-forge/buildlink3.mk
@@ -1,22 +1,15 @@
-# $NetBSD: buildlink3.mk,v 1.8 2007/01/07 12:25:54 wiz Exp $
+# $NetBSD: buildlink3.mk,v 1.9 2009/03/20 19:24:57 joerg Exp $
 
-BUILDLINK_DEPTH:=		${BUILDLINK_DEPTH}+
-OCTAVE_FORGE_BUILDLINK3_MK:=	${OCTAVE_FORGE_BUILDLINK3_MK}+
+BUILDLINK_TREE+=	octave-forge
 
-.if !empty(BUILDLINK_DEPTH:M+)
-BUILDLINK_DEPENDS+=	octave-forge
-.endif
+.if !defined(OCTAVE_FORGE_BUILDLINK3_MK)
+OCTAVE_FORGE_BUILDLINK3_MK:=
 
-BUILDLINK_PACKAGES:=	${BUILDLINK_PACKAGES:Noctave-forge}
-BUILDLINK_PACKAGES+=	octave-forge
-BUILDLINK_ORDER:=	${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}octave-forge
-
-.if !empty(OCTAVE_FORGE_BUILDLINK3_MK:M+)
 BUILDLINK_API_DEPENDS.octave-forge+=	octave-forge>=2005.06.13
 BUILDLINK_ABI_DEPENDS.octave-forge?=	octave-forge>=2006.03.17nb1
 BUILDLINK_PKGSRCDIR.octave-forge?=	../../math/octave-forge
-.endif	# OCTAVE_FORGE_BUILDLINK3_MK
 
 .include "../../math/octave/buildlink3.mk"
+.endif # OCTAVE_FORGE_BUILDLINK3_MK
 
-BUILDLINK_DEPTH:=		${BUILDLINK_DEPTH:S/+$//}
+BUILDLINK_TREE+=	-octave-forge
diff --git a/math/octave/buildlink3.mk b/math/octave/buildlink3.mk
index 254bccfeed8..4f9a976f704 100644
--- a/math/octave/buildlink3.mk
+++ b/math/octave/buildlink3.mk
@@ -1,21 +1,13 @@
-# $NetBSD: buildlink3.mk,v 1.12 2008/01/11 01:23:43 adam Exp $
+# $NetBSD: buildlink3.mk,v 1.13 2009/03/20 19:24:57 joerg Exp $
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH}+
-OCTAVE_BUILDLINK3_MK:=	${OCTAVE_BUILDLINK3_MK}+
+BUILDLINK_TREE+=	octave
 
-.if !empty(BUILDLINK_DEPTH:M+)
-BUILDLINK_DEPENDS+=	octave
-.endif
-
-BUILDLINK_PACKAGES:=	${BUILDLINK_PACKAGES:Noctave}
-BUILDLINK_PACKAGES+=	octave
-BUILDLINK_ORDER:=	${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}octave
+.if !defined(OCTAVE_BUILDLINK3_MK)
+OCTAVE_BUILDLINK3_MK:=
 
-.if !empty(OCTAVE_BUILDLINK3_MK:M+)
 BUILDLINK_API_DEPENDS.octave+=	octave>=3.0.0
 BUILDLINK_ABI_DEPENDS.octave+=	octave>=3.0.0
 BUILDLINK_PKGSRCDIR.octave?=	../../math/octave
-.endif	# OCTAVE_BUILDLINK3_MK
 
 .include "../../mk/bsd.fast.prefs.mk"
 
@@ -30,5 +22,6 @@ BUILDLINK_PKGSRCDIR.octave?=	../../math/octave
 .include "../../math/blas/buildlink3.mk"
 .include "../../math/fftw/buildlink3.mk"
 .include "../../math/lapack/buildlink3.mk"
+.endif # OCTAVE_BUILDLINK3_MK
 
-BUILDLINK_DEPTH:=		${BUILDLINK_DEPTH:S/+$//}
+BUILDLINK_TREE+=	-octave
diff --git a/math/pari/buildlink3.mk b/math/pari/buildlink3.mk
index 164dabeafd8..4878aaaae75 100644
--- a/math/pari/buildlink3.mk
+++ b/math/pari/buildlink3.mk
@@ -1,20 +1,13 @@
-# $NetBSD: buildlink3.mk,v 1.7 2006/07/08 23:10:59 jlam Exp $
+# $NetBSD: buildlink3.mk,v 1.8 2009/03/20 19:24:58 joerg Exp $
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH}+
-PARI_BUILDLINK3_MK:=	${PARI_BUILDLINK3_MK}+
+BUILDLINK_TREE+=	pari
 
-.if !empty(BUILDLINK_DEPTH:M+)
-BUILDLINK_DEPENDS+=	pari
-.endif
+.if !defined(PARI_BUILDLINK3_MK)
+PARI_BUILDLINK3_MK:=
 
-BUILDLINK_PACKAGES:=	${BUILDLINK_PACKAGES:Npari}
-BUILDLINK_PACKAGES+=	pari
-BUILDLINK_ORDER:=	${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}pari
-
-.if !empty(PARI_BUILDLINK3_MK:M+)
 BUILDLINK_API_DEPENDS.pari+=	pari>=2.1.5nb1
 BUILDLINK_ABI_DEPENDS.pari+=	pari>=2.1.6nb1
 BUILDLINK_PKGSRCDIR.pari?=	../../math/pari
-.endif	# PARI_BUILDLINK3_MK
+.endif # PARI_BUILDLINK3_MK
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH:S/+$//}
+BUILDLINK_TREE+=	-pari
diff --git a/math/py-Numeric/buildlink3.mk b/math/py-Numeric/buildlink3.mk
index 48ee19f74d9..0ff98324850 100644
--- a/math/py-Numeric/buildlink3.mk
+++ b/math/py-Numeric/buildlink3.mk
@@ -1,22 +1,15 @@
-# $NetBSD: buildlink3.mk,v 1.14 2009/03/20 17:30:11 joerg Exp $
+# $NetBSD: buildlink3.mk,v 1.15 2009/03/20 19:24:58 joerg Exp $
 
-BUILDLINK_DEPTH:=		${BUILDLINK_DEPTH}+
-PY_NUMERIC_BUILDLINK3_MK:=	${PY_NUMERIC_BUILDLINK3_MK}+
+BUILDLINK_TREE+=	pynumeric
 
-.if !empty(BUILDLINK_DEPTH:M+)
-BUILDLINK_DEPENDS+=	pynumeric
-.endif
+.if !defined(PY_NUMERIC_BUILDLINK3_MK)
+PY_NUMERIC_BUILDLINK3_MK:=
 
-BUILDLINK_PACKAGES:=	${BUILDLINK_PACKAGES:Npynumeric}
-BUILDLINK_PACKAGES+=	pynumeric
-BUILDLINK_ORDER:=	${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}pynumeric
-
-.if !empty(PY_NUMERIC_BUILDLINK3_MK:M+)
 .  include "../../lang/python/pyversion.mk"
 
 BUILDLINK_API_DEPENDS.pynumeric+=	${PYPKGPREFIX}-Numeric-[0-9]*
 BUILDLINK_ABI_DEPENDS.pynumeric+=	${PYPKGPREFIX}-Numeric>=23.7nb1
 BUILDLINK_PKGSRCDIR.pynumeric?=	../../math/py-Numeric
-.endif	# PY_NUMERIC_BUILDLINK3_MK
+.endif # PY_NUMERIC_BUILDLINK3_MK
 
-BUILDLINK_DEPTH:=		${BUILDLINK_DEPTH:S/+$//}
+BUILDLINK_TREE+=	-pynumeric
diff --git a/math/py-ephem/buildlink3.mk b/math/py-ephem/buildlink3.mk
index 660c11f21b2..351d5f1233c 100644
--- a/math/py-ephem/buildlink3.mk
+++ b/math/py-ephem/buildlink3.mk
@@ -1,19 +1,12 @@
-# $NetBSD: buildlink3.mk,v 1.1.1.1 2006/11/13 15:55:55 wulf Exp $
+# $NetBSD: buildlink3.mk,v 1.2 2009/03/20 19:24:58 joerg Exp $
 
-BUILDLINK_DEPTH:=		${BUILDLINK_DEPTH}+
-PY_EPHEM_BUILDLINK3_MK:=	${PY_EPHEM_BUILDLINK3_MK}+
+BUILDLINK_TREE+=	py-ephem
 
-.if ${BUILDLINK_DEPTH} == "+"
-BUILDLINK_DEPENDS+=	py-ephem
-.endif
+.if !defined(PY_EPHEM_BUILDLINK3_MK)
+PY_EPHEM_BUILDLINK3_MK:=
 
-BUILDLINK_PACKAGES:=	${BUILDLINK_PACKAGES:Npy-ephem}
-BUILDLINK_PACKAGES+=	py-ephem
-BUILDLINK_ORDER:=	${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}py-ephem
-
-.if ${PY_EPHEM_BUILDLINK3_MK} == "+"
 BUILDLINK_API_DEPENDS.py-ephem+=	${PYPKGPREFIX}-ephem>=3.7b
 BUILDLINK_PKGSRCDIR.py-ephem?=	../../math/py-ephem
-.endif	# PY_EPHEM_BUILDLINK3_MK
+.endif # PY_EPHEM_BUILDLINK3_MK
 
-BUILDLINK_DEPTH:=		${BUILDLINK_DEPTH:S/+$//}
+BUILDLINK_TREE+=	-py-ephem
diff --git a/math/py-fpconst/buildlink3.mk b/math/py-fpconst/buildlink3.mk
index 0e63e393ba9..8bb6497ec62 100644
--- a/math/py-fpconst/buildlink3.mk
+++ b/math/py-fpconst/buildlink3.mk
@@ -1,22 +1,15 @@
-# $NetBSD: buildlink3.mk,v 1.7 2009/03/20 17:30:11 joerg Exp $
+# $NetBSD: buildlink3.mk,v 1.8 2009/03/20 19:24:58 joerg Exp $
 
-BUILDLINK_DEPTH:=		${BUILDLINK_DEPTH}+
-PY_FPCONST_BUILDLINK3_MK:=	${PY_FPCONST_BUILDLINK3_MK}+
+BUILDLINK_TREE+=	py-fpconst
 
-.if !empty(BUILDLINK_DEPTH:M+)
-BUILDLINK_DEPENDS+=	py-fpconst
-.endif
+.if !defined(PY_FPCONST_BUILDLINK3_MK)
+PY_FPCONST_BUILDLINK3_MK:=
 
-BUILDLINK_PACKAGES:=	${BUILDLINK_PACKAGES:Npy-fpconst}
-BUILDLINK_PACKAGES+=	py-fpconst
-BUILDLINK_ORDER:=	${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}py-fpconst
-
-.if !empty(PY_FPCONST_BUILDLINK3_MK:M+)
 .include "../../lang/python/pyversion.mk"
 
 BUILDLINK_API_DEPENDS.py-fpconst+=	${PYPKGPREFIX}-fpconst>=0.7.0
 BUILDLINK_ABI_DEPENDS.py-fpconst?=	${PYPKGPREFIX}-fpconst>=0.7.0nb1
 BUILDLINK_PKGSRCDIR.py-fpconst?=	../../math/py-fpconst
-.endif	# PY_FPCONST_BUILDLINK3_MK
+.endif # PY_FPCONST_BUILDLINK3_MK
 
-BUILDLINK_DEPTH:=		${BUILDLINK_DEPTH:S/+$//}
+BUILDLINK_TREE+=	-py-fpconst
diff --git a/math/py-numarray/buildlink3.mk b/math/py-numarray/buildlink3.mk
index f055cba912c..6991c592430 100644
--- a/math/py-numarray/buildlink3.mk
+++ b/math/py-numarray/buildlink3.mk
@@ -1,22 +1,15 @@
-# $NetBSD: buildlink3.mk,v 1.8 2009/03/20 17:30:11 joerg Exp $
+# $NetBSD: buildlink3.mk,v 1.9 2009/03/20 19:24:58 joerg Exp $
 
-BUILDLINK_DEPTH:=			${BUILDLINK_DEPTH}+
-PY_NUMARRAY_BUILDLINK3_MK:=	${PY_NUMARRAY_BUILDLINK3_MK}+
+BUILDLINK_TREE+=	pynumarray
 
-.if !empty(BUILDLINK_DEPTH:M+)
-BUILDLINK_DEPENDS+=	pynumarray
-.endif
+.if !defined(PY_NUMARRAY_BUILDLINK3_MK)
+PY_NUMARRAY_BUILDLINK3_MK:=
 
-BUILDLINK_PACKAGES:=	${BUILDLINK_PACKAGES:Npynumarray}
-BUILDLINK_PACKAGES+=	pynumarray
-BUILDLINK_ORDER:=	${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}pynumarray
-
-.if !empty(PY_NUMARRAY_BUILDLINK3_MK:M+)
 .include "../../lang/python/pyversion.mk"
 
 BUILDLINK_API_DEPENDS.pynumarray+=	${PYPKGPREFIX}-numarray>=1.1.1
 BUILDLINK_ABI_DEPENDS.pynumarray?=	${PYPKGPREFIX}-numarray>=1.3.3nb1
 BUILDLINK_PKGSRCDIR.pynumarray?=	../../math/py-numarray
-.endif	# PY_NUMARRAY_BUILDLINK3_MK
+.endif # PY_NUMARRAY_BUILDLINK3_MK
 
-BUILDLINK_DEPTH:=			${BUILDLINK_DEPTH:S/+$//}
+BUILDLINK_TREE+=	-pynumarray
diff --git a/math/py-numpy/buildlink3.mk b/math/py-numpy/buildlink3.mk
index a1757419913..03fbb7f60df 100644
--- a/math/py-numpy/buildlink3.mk
+++ b/math/py-numpy/buildlink3.mk
@@ -1,24 +1,17 @@
-# $NetBSD: buildlink3.mk,v 1.2 2009/03/20 17:30:11 joerg Exp $
+# $NetBSD: buildlink3.mk,v 1.3 2009/03/20 19:24:58 joerg Exp $
 
-BUILDLINK_DEPTH:=		${BUILDLINK_DEPTH}+
-PY_NUMPY_BUILDLINK3_MK:=	${PY_NUMPY_BUILDLINK3_MK}+
+BUILDLINK_TREE+=	pynumpy
 
-.if ${BUILDLINK_DEPTH} == "+"
-BUILDLINK_DEPENDS+=	pynumpy
-.endif
+.if !defined(PY_NUMPY_BUILDLINK3_MK)
+PY_NUMPY_BUILDLINK3_MK:=
 
-BUILDLINK_PACKAGES:=	${BUILDLINK_PACKAGES:Npynumpy}
-BUILDLINK_PACKAGES+=	pynumpy
-BUILDLINK_ORDER:=	${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}pynumpy
-
-.if ${PY_NUMPY_BUILDLINK3_MK} == "+"
 .include "../../lang/python/pyversion.mk"
 
 BUILDLINK_API_DEPENDS.pynumpy+=	${PYPKGPREFIX}-numpy>=1.0
 BUILDLINK_PKGSRCDIR.pynumpy?=	../../math/py-numpy
-.endif	# PY_NUMPY_BUILDLINK3_MK
 
 .include "../../math/blas/buildlink3.mk"
 .include "../../math/lapack/buildlink3.mk"
+.endif # PY_NUMPY_BUILDLINK3_MK
 
-BUILDLINK_DEPTH:=		${BUILDLINK_DEPTH:S/+$//}
+BUILDLINK_TREE+=	-pynumpy
diff --git a/math/qalculate/buildlink3.mk b/math/qalculate/buildlink3.mk
index aa2f3de2eb9..d6fb715247f 100644
--- a/math/qalculate/buildlink3.mk
+++ b/math/qalculate/buildlink3.mk
@@ -1,24 +1,17 @@
-# $NetBSD: buildlink3.mk,v 1.9 2006/07/08 23:11:00 jlam Exp $
+# $NetBSD: buildlink3.mk,v 1.10 2009/03/20 19:24:58 joerg Exp $
 
-BUILDLINK_DEPTH:=		${BUILDLINK_DEPTH}+
-QALCULATE_BUILDLINK3_MK:=	${QALCULATE_BUILDLINK3_MK}+
+BUILDLINK_TREE+=	qalculate
 
-.if !empty(BUILDLINK_DEPTH:M+)
-BUILDLINK_DEPENDS+=	qalculate
-.endif
+.if !defined(QALCULATE_BUILDLINK3_MK)
+QALCULATE_BUILDLINK3_MK:=
 
-BUILDLINK_PACKAGES:=	${BUILDLINK_PACKAGES:Nqalculate}
-BUILDLINK_PACKAGES+=	qalculate
-BUILDLINK_ORDER:=	${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}qalculate
-
-.if !empty(QALCULATE_BUILDLINK3_MK:M+)
 BUILDLINK_API_DEPENDS.qalculate+=	qalculate>=0.8.2
 BUILDLINK_ABI_DEPENDS.qalculate?=	qalculate>=0.8.2nb2
 BUILDLINK_PKGSRCDIR.qalculate?=	../../math/qalculate
-.endif	# QALCULATE_BUILDLINK3_MK
 
 .include "../../devel/glib2/buildlink3.mk"
 .include "../../math/cln/buildlink3.mk"
 .include "../../textproc/libxml2/buildlink3.mk"
+.endif # QALCULATE_BUILDLINK3_MK
 
-BUILDLINK_DEPTH:=		${BUILDLINK_DEPTH:S/+$//}
+BUILDLINK_TREE+=	-qalculate
diff --git a/math/qhull/buildlink3.mk b/math/qhull/buildlink3.mk
index 8f404b2e8f8..f8cbaac5a74 100644
--- a/math/qhull/buildlink3.mk
+++ b/math/qhull/buildlink3.mk
@@ -1,19 +1,12 @@
-# $NetBSD: buildlink3.mk,v 1.1.1.1 2007/09/19 18:00:54 drochner Exp $
+# $NetBSD: buildlink3.mk,v 1.2 2009/03/20 19:24:58 joerg Exp $
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH}+
-QHULL_BUILDLINK3_MK:=	${QHULL_BUILDLINK3_MK}+
+BUILDLINK_TREE+=	qhull
 
-.if ${BUILDLINK_DEPTH} == "+"
-BUILDLINK_DEPENDS+=	qhull
-.endif
+.if !defined(QHULL_BUILDLINK3_MK)
+QHULL_BUILDLINK3_MK:=
 
-BUILDLINK_PACKAGES:=	${BUILDLINK_PACKAGES:Nqhull}
-BUILDLINK_PACKAGES+=	qhull
-BUILDLINK_ORDER:=	${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}qhull
-
-.if ${QHULL_BUILDLINK3_MK} == "+"
 BUILDLINK_API_DEPENDS.qhull+=	qhull>=2003.1
 BUILDLINK_PKGSRCDIR.qhull?=	../../math/qhull
-.endif	# QHULL_BUILDLINK3_MK
+.endif # QHULL_BUILDLINK3_MK
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH:S/+$//}
+BUILDLINK_TREE+=	-qhull
diff --git a/math/scilab/buildlink3.mk b/math/scilab/buildlink3.mk
index 8c2efcb57f9..998391aee7a 100644
--- a/math/scilab/buildlink3.mk
+++ b/math/scilab/buildlink3.mk
@@ -1,29 +1,22 @@
-# $NetBSD: buildlink3.mk,v 1.12 2007/03/28 21:18:52 dmcmahill Exp $
+# $NetBSD: buildlink3.mk,v 1.13 2009/03/20 19:24:58 joerg Exp $
 #
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH}+
-SCILAB_BUILDLINK3_MK:=	${SCILAB_BUILDLINK3_MK}+
+BUILDLINK_TREE+=	scilab
 
-.if !empty(BUILDLINK_DEPTH:M+)
-BUILDLINK_DEPENDS+=	scilab
-.endif
+.if !defined(SCILAB_BUILDLINK3_MK)
+SCILAB_BUILDLINK3_MK:=
 
-BUILDLINK_PACKAGES:=	${BUILDLINK_PACKAGES:Nscilab}
-BUILDLINK_PACKAGES+=	scilab
-BUILDLINK_ORDER:=	${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}scilab
-
-.if !empty(SCILAB_BUILDLINK3_MK:M+)
 BUILDLINK_API_DEPENDS.scilab+=	scilab>=4.1
 BUILDLINK_ABI_DEPENDS.scilab?=	scilab>=4.1
 BUILDLINK_PKGSRCDIR.scilab?=	../../math/scilab
 
 BUILDLINK_FILES.scilab+=	lib/scilab-${SCIVERSION}/Version.incl
-.endif	# SCILAB_BUILDLINK3_MK
 
 SCI=	${BUILDLINK_DIR}/lib/scilab-4.1
 CONFIGURE_ENV+=	SCI=${SCI:Q}
 MAKE_ENV+=	SCI=${SCI:Q}
 
 SCIVERSION=	4.1
+.endif # SCILAB_BUILDLINK3_MK
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH:S/+$//}
+BUILDLINK_TREE+=	-scilab
diff --git a/math/slatec/buildlink3.mk b/math/slatec/buildlink3.mk
index ac435ccad69..c2b98600d20 100644
--- a/math/slatec/buildlink3.mk
+++ b/math/slatec/buildlink3.mk
@@ -1,20 +1,13 @@
-# $NetBSD: buildlink3.mk,v 1.6 2006/07/08 23:11:00 jlam Exp $
+# $NetBSD: buildlink3.mk,v 1.7 2009/03/20 19:24:59 joerg Exp $
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH}+
-SLATEC_BUILDLINK3_MK:=	${SLATEC_BUILDLINK3_MK}+
+BUILDLINK_TREE+=	slatec
 
-.if !empty(BUILDLINK_DEPTH:M+)
-BUILDLINK_DEPENDS+=	slatec
-.endif
+.if !defined(SLATEC_BUILDLINK3_MK)
+SLATEC_BUILDLINK3_MK:=
 
-BUILDLINK_PACKAGES:=	${BUILDLINK_PACKAGES:Nslatec}
-BUILDLINK_PACKAGES+=	slatec
-BUILDLINK_ORDER:=	${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}slatec
-
-.if !empty(SLATEC_BUILDLINK3_MK:M+)
 BUILDLINK_API_DEPENDS.slatec+=	slatec>=4.1nb1
 BUILDLINK_ABI_DEPENDS.slatec+=	slatec>=4.1nb2
 BUILDLINK_PKGSRCDIR.slatec?=	../../math/slatec
-.endif	# SLATEC_BUILDLINK3_MK
+.endif # SLATEC_BUILDLINK3_MK
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH:S/+$//}
+BUILDLINK_TREE+=	-slatec
diff --git a/math/superlu/buildlink3.mk b/math/superlu/buildlink3.mk
index 8a2d5eaba90..9d51b55e623 100644
--- a/math/superlu/buildlink3.mk
+++ b/math/superlu/buildlink3.mk
@@ -1,20 +1,13 @@
-# $NetBSD: buildlink3.mk,v 1.5 2006/07/08 23:11:00 jlam Exp $
+# $NetBSD: buildlink3.mk,v 1.6 2009/03/20 19:24:59 joerg Exp $
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH}+
-SUPERLU_BUILDLINK3_MK:=	${SUPERLU_BUILDLINK3_MK}+
+BUILDLINK_TREE+=	superlu
 
-.if !empty(BUILDLINK_DEPTH:M+)
-BUILDLINK_DEPENDS+=	superlu
-.endif
+.if !defined(SUPERLU_BUILDLINK3_MK)
+SUPERLU_BUILDLINK3_MK:=
 
-BUILDLINK_PACKAGES:=	${BUILDLINK_PACKAGES:Nsuperlu}
-BUILDLINK_PACKAGES+=	superlu
-BUILDLINK_ORDER:=	${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}superlu
-
-.if !empty(SUPERLU_BUILDLINK3_MK:M+)
 BUILDLINK_API_DEPENDS.superlu+=	superlu>=2.0nb2
 BUILDLINK_PKGSRCDIR.superlu?=	../../math/superlu
 BUILDLINK_DEPMETHOD.superlu?=	build
-.endif	# SUPERLU_BUILDLINK3_MK
+.endif # SUPERLU_BUILDLINK3_MK
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH:S/+$//}
+BUILDLINK_TREE+=	-superlu
diff --git a/math/tasp-vsipl/buildlink3.mk b/math/tasp-vsipl/buildlink3.mk
index f6060dba78a..c24bf4bf771 100644
--- a/math/tasp-vsipl/buildlink3.mk
+++ b/math/tasp-vsipl/buildlink3.mk
@@ -1,20 +1,13 @@
-# $NetBSD: buildlink3.mk,v 1.6 2006/07/08 23:11:00 jlam Exp $
+# $NetBSD: buildlink3.mk,v 1.7 2009/03/20 19:24:59 joerg Exp $
 
-BUILDLINK_DEPTH:=		${BUILDLINK_DEPTH}+
-TASP_VSIPL_BUILDLINK3_MK:=	${TASP_VSIPL_BUILDLINK3_MK}+
+BUILDLINK_TREE+=	tasp-vsipl
 
-.if !empty(BUILDLINK_DEPTH:M+)
-BUILDLINK_DEPENDS+=	tasp-vsipl
-.endif
+.if !defined(TASP_VSIPL_BUILDLINK3_MK)
+TASP_VSIPL_BUILDLINK3_MK:=
 
-BUILDLINK_PACKAGES:=	${BUILDLINK_PACKAGES:Ntasp-vsipl}
-BUILDLINK_PACKAGES+=	tasp-vsipl
-BUILDLINK_ORDER:=	${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}tasp-vsipl
-
-.if !empty(TASP_VSIPL_BUILDLINK3_MK:M+)
 BUILDLINK_API_DEPENDS.tasp-vsipl+=	tasp-vsipl>=20030710
 BUILDLINK_ABI_DEPENDS.tasp-vsipl?=	tasp-vsipl>=20030710nb1
 BUILDLINK_PKGSRCDIR.tasp-vsipl?=	../../math/tasp-vsipl
-.endif	# TASP_VSIPL_BUILDLINK3_MK
+.endif # TASP_VSIPL_BUILDLINK3_MK
 
-BUILDLINK_DEPTH:=		${BUILDLINK_DEPTH:S/+$//}
+BUILDLINK_TREE+=	-tasp-vsipl
diff --git a/math/udunits/buildlink3.mk b/math/udunits/buildlink3.mk
index cede744b754..01324f03be4 100644
--- a/math/udunits/buildlink3.mk
+++ b/math/udunits/buildlink3.mk
@@ -1,21 +1,14 @@
-# $NetBSD: buildlink3.mk,v 1.5 2006/07/08 23:11:00 jlam Exp $
+# $NetBSD: buildlink3.mk,v 1.6 2009/03/20 19:24:59 joerg Exp $
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH}+
-UDUNITS_BUILDLINK3_MK:=	${UDUNITS_BUILDLINK3_MK}+
+BUILDLINK_TREE+=	udunits
 
-.if !empty(BUILDLINK_DEPTH:M+)
-BUILDLINK_DEPENDS+=	udunits
-.endif
+.if !defined(UDUNITS_BUILDLINK3_MK)
+UDUNITS_BUILDLINK3_MK:=
 
-BUILDLINK_PACKAGES:=	${BUILDLINK_PACKAGES:Nudunits}
-BUILDLINK_PACKAGES+=	udunits
-BUILDLINK_ORDER:=	${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}udunits
-
-.if !empty(UDUNITS_BUILDLINK3_MK:M+)
 BUILDLINK_API_DEPENDS.udunits+=	udunits>=1.11.7
 BUILDLINK_PKGSRCDIR.udunits?=	../../math/udunits
 BUILDLINK_DEPMETHOD.udunits?=	build
 BUILDLINK_FILES.udunits=	include/udunits.inc
-.endif	# UDUNITS_BUILDLINK3_MK
+.endif # UDUNITS_BUILDLINK3_MK
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH:S/+$//}
+BUILDLINK_TREE+=	-udunits
diff --git a/math/yorick/buildlink3.mk b/math/yorick/buildlink3.mk
index 8f9b522e7f7..d84d6be16a5 100644
--- a/math/yorick/buildlink3.mk
+++ b/math/yorick/buildlink3.mk
@@ -1,21 +1,14 @@
-# $NetBSD: buildlink3.mk,v 1.6 2006/07/08 23:11:00 jlam Exp $
+# $NetBSD: buildlink3.mk,v 1.7 2009/03/20 19:24:59 joerg Exp $
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH}+
-YORICK_BUILDLINK3_MK:=	${YORICK_BUILDLINK3_MK}+
+BUILDLINK_TREE+=	yorick
 
-.if !empty(BUILDLINK_DEPTH:M+)
-BUILDLINK_DEPENDS+=	yorick
-.endif
+.if !defined(YORICK_BUILDLINK3_MK)
+YORICK_BUILDLINK3_MK:=
 
-BUILDLINK_PACKAGES:=	${BUILDLINK_PACKAGES:Nyorick}
-BUILDLINK_PACKAGES+=	yorick
-BUILDLINK_ORDER:=	${BUILDLINK_ORDER} ${BUILDLINK_DEPTH}yorick
-
-.if !empty(YORICK_BUILDLINK3_MK:M+)
 BUILDLINK_API_DEPENDS.yorick+=	yorick>=1.5.12
 BUILDLINK_DEPMETHOD.yorick?=	build
 BUILDLINK_ABI_DEPENDS.yorick?=	yorick>=1.6.02nb1
 BUILDLINK_PKGSRCDIR.yorick?=	../../math/yorick
-.endif	# YORICK_BUILDLINK3_MK
+.endif # YORICK_BUILDLINK3_MK
 
-BUILDLINK_DEPTH:=	${BUILDLINK_DEPTH:S/+$//}
+BUILDLINK_TREE+=	-yorick