Create a mechanism for providing fine-grained build order dependencies

during SUBDIR_PARALLEL builds.  This augments the coarse .WAIT mechanism,
which is still useful if you've got a situation such as "almost everything
depends on A and B".

Because the parallel subdir mechanism uses non-obvious mangling of
target names, which should probably remain a private detail of the
implementation, it's not easy to do things like "libfoo: libbar", so
instead the new mechanism lets you set a variable that lists dependencies:

  SUBDIR_DEPEND_libfoo= libgroodah libpouet

Note that while I'm using libraries as an example here, it really has
nothing to do with the generated library files.  This is really saying
"build in directory libfoo after building in the libgroodah and libpouet
directories."

This updates lib/Makefile with dependency information based on the old
almost-accurate comment block and by combing through lib/* makefiles
looking for LDADD dependencies to other libraries within lib/*.

Reviewed by:	Jia-Shiun Li <jiashiun@gmail.com>

lib/Makefile

@@ -3,82 +3,43 @@
 
 .include <src.opts.mk>
 
-# To satisfy shared library or ELF linkage when only the libraries being
+# The SUBDIR_ORDERED list is a small set of libraries which are used by many
-# built are visible:
+# of the other libraries.  These are built first with a .WAIT between them
-#
+# and the main list to avoid needing a SUBDIR_DEPEND line on every library
-# csu must be built before all shared libaries for ELF.
+# naming just these few items.
-# libc must be built before all other shared libraries.
-# libbsm must be built before libauditd.
-# libcom_err must be built before libpam.
-# libcrypt must be built before libpam.
-# libkvm must be built before libdevstat.
-# libldns must be built before libunbound.
-# msun must be built before libg++ and libstdc++.
-# libmd must be built before libatm, libopie, libradius, and libtacplus.
-# ncurses must be built before libdialog, libedit and libreadline.
-# libnetgraph must be built before libbsnmp/modules/snmp_netgraph.
-# libopie must be built before libpam.
-# libradius must be built before libpam.
-# librpcsvc must be built before libpam.
-# libsbuf must be built before libcam.
-# libtacplus must be built before libpam.
-# libutil must be built before libpam.
-# libypclnt must be built before libpam.
-# libgssapi must be built before librpcsec_gss
-#
-# Otherwise, the SUBDIR list should be in alphabetical order.
-#
-# Except it appears bind needs to be compiled last
 
 SUBDIR_ORDERED=	${_csu} \
 	.WAIT \
 	libc \
 	libc_nonshared \
-	.WAIT \
-	msun \
-	.WAIT \
-	libbsm \
-	libauditd \
-	libutil \
-	libpjdlog \
-	libnv \
-	${_libcapsicum} \
 	libcompiler_rt \
-	libcrypt \
+	${_libcplusplus} \
-	libelf \
-	${_libiconv_modules} \
-	libkvm \
-	${_libldns} \
-	libmd \
-	ncurses \
-	${_libnetgraph} \
-	libradius \
-	librpcsvc \
-	libsbuf \
-	libtacplus \
-	${_libypclnt} \
 	${_libcxxrt} \
-	${_libcplusplus}
+	libelf \
+	msun
 
-.if ${MK_KERBEROS_SUPPORT} != "no"
+# The main list; please keep these sorted alphabetically.
-SUBDIR_ORDERED+=	libcom_err
-.endif
 
 SUBDIR=	${SUBDIR_ORDERED} \
 	.WAIT \
 	libalias \
 	libarchive \
 	${_libatm} \
+	libauditd \
 	libbegemot \
 	libblocksruntime \
 	${_libbluetooth} \
 	${_libbsnmp} \
 	libbsdstat \
+	libbsm \
 	libbz2 \
 	libcalendar \
 	libcam \
+	${_libcapsicum} \
 	${_libcasper} \
+	${_libcom_err} \
 	libcompat \
+	libcrypt \
 	libdevinfo \
 	libdevstat \
 	libdwarf \
@@ -91,26 +52,36 @@ SUBDIR=	${SUBDIR_ORDERED} \
 	${_libgpib} \
 	${_libgssapi} \
 	${_librpcsec_gss} \
+	${_libiconv_modules} \
 	libipsec \
 	libjail \
 	libkiconv \
+	libkvm \
+	${_libldns} \
 	liblzma \
 	libmagic \
 	libmandoc \
 	libmemstat \
+	libmd \
 	${_libmilter} \
 	${_libmp} \
 	${_libnandfs} \
 	libnetbsd \
+	${_libnetgraph} \
 	${_libngatm} \
+	libnv \
 	libopie \
 	libpam \
 	libpcap \
+	libpjdlog \
 	${_libpmc} \
 	${_libproc} \
 	libprocstat \
+	libradius \
+	librpcsvc \
 	librt \
 	${_librtld_db} \
+	libsbuf \
 	${_libsdp} \
 	${_libsm} \
 	${_libsmb} \
@@ -119,6 +90,7 @@ SUBDIR=	${SUBDIR_ORDERED} \
 	libstand \
 	libstdbuf \
 	libstdthreads \
+	libtacplus \
 	${_libtelnet} \
 	${_libthr} \
 	libthread_db \
@@ -129,16 +101,51 @@ SUBDIR=	${SUBDIR_ORDERED} \
 	${_libunbound} \
 	${_libusbhid} \
 	${_libusb} \
+	libutil \
 	${_libvgl} \
 	${_libvmmapi} \
 	libwrap \
 	liby \
+	${_libypclnt} \
 	libz \
+	ncurses \
 	${_atf} \
 	${_clang} \
 	${_cuse} \
 	${_tests}
 
+# Inter-library dependencies.  When the makefile for a library contains LDADD
+# libraries, those libraries should be listed as build order dependencies here.
+
+SUBDIR_DEPEND_libarchive= libz libbz2 libexpat liblzma libmd
+SUBDIR_DEPEND_libatm= libmd
+SUBDIR_DEPEND_libauditdm= libbsm
+SUBDIR_DEPEND_libbsnmp= ${_libnetgraph}
+SUBDIR_DEPEND_libc++= libcxxrt
+SUBDIR_DEPEND_libc= libcompiler_rt
+SUBDIR_DEPEND_libcam= libsbuf
+SUBDIR_DEPEND_libcapsicum= libnv
+SUBDIR_DEPEND_libcasper= libcapsicum libnv libpjdlog
+SUBDIR_DEPEND_libdevstat= libkvm
+SUBDIR_DEPEND_libdiaglog= ncurses
+SUBDIR_DEPEND_libedit= ncurses
+SUBDIR_DEPEND_libg++= msun
+SUBDIR_DEPEND_libgeom= libexpat libsbuf
+SUBDIR_DEPEND_liblibrpcsec_gss= libgssapi
+SUBDIR_DEPEND_libmagic= libz
+SUBDIR_DEPEND_libmemstat= libkvm
+SUBDIR_DEPEND_libopie= libmd
+SUBDIR_DEPEND_libpam= libcrypt libopie libradius librpcsvc libtacplus libutil ${_libypclnt} ${_libcom_err} 
+SUBDIR_DEPEND_libpjdlog= libutil
+SUBDIR_DEPEND_libprocstat= libkvm libutil
+SUBDIR_DEPEND_libradius= libmd
+SUBDIR_DEPEND_libreadline= ncurses
+SUBDIR_DEPEND_libsmb= libkiconv
+SUBDIR_DEPEND_libstdc++= msun
+SUBDIR_DEPEND_libtacplus= libmd
+SUBDIR_DEPEND_libulog= libmd
+SUBDIR_DEPEND_libunbound= ${_libldns}
+
 .if exists(${.CURDIR}/csu/${MACHINE_ARCH}-elf)
 _csu=csu/${MACHINE_ARCH}-elf
 .elif exists(${.CURDIR}/csu/${MACHINE_ARCH})
@@ -190,6 +197,10 @@ _librpcsec_gss=	librpcsec_gss
 _libiconv_modules=	libiconv_modules
 .endif
 
+.if ${MK_KERBEROS_SUPPORT} != "no"
+_libcom_err= libcom_err
+.endif
+
 .if ${MK_LDNS} != "no"
 _libldns=	libldns
 .endif

share/mk/bsd.subdir.mk

@@ -80,7 +80,11 @@ __subdir_targets=
 __subdir_targets+= .WAIT
 .else
 __subdir_targets+= ${__target}_subdir_${__dir}
-${__target}_subdir_${__dir}: .MAKE
+__deps=
+.for __dep in ${SUBDIR_DEPEND_${__dir}}
+__deps+= ${__target}_subdir_${__dep}
+.endfor
+${__target}_subdir_${__dir}: .MAKE ${__deps}
 .if !defined(NO_SUBDIR)
 	@${_+_}set -e; \
 		if test -d ${.CURDIR}/${__dir}.${MACHINE_ARCH}; then \