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authorPatrick Simianer <simianer@cl.uni-heidelberg.de>2012-05-13 03:35:30 +0200
committerPatrick Simianer <simianer@cl.uni-heidelberg.de>2012-05-13 03:35:30 +0200
commit670a8f984fc6d8342180c59ae9e96b0b76f34d3d (patch)
tree9f2ce7eec1a77e56b3bb1ad0ad40f212d7a996b0 /jam-files/boost-build/build/targets.jam
parenteb3ee28dc0eb1d3e5ed01ba0df843be329ae450d (diff)
parent2f64af3e06a518b93f7ca2c30a9d0aeb2c947031 (diff)
Merge remote-tracking branch 'upstream/master'
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diff --git a/jam-files/boost-build/build/targets.jam b/jam-files/boost-build/build/targets.jam
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+# Copyright Vladimir Prus 2002.
+# Copyright Rene Rivera 2006.
+#
+# Distributed under the Boost Software License, Version 1.0.
+# (See accompanying file LICENSE_1_0.txt or copy at
+# http://www.boost.org/LICENSE_1_0.txt)
+
+# Supports 'abstract' targets, which are targets explicitly defined in a
+# Jamfile.
+#
+# Abstract targets are represented by classes derived from 'abstract-target'
+# class. The first abstract target is 'project-target', which is created for
+# each Jamfile, and can be obtained by the 'target' rule in the Jamfile's module
+# (see project.jam).
+#
+# Project targets keep a list of 'main-target' instances. A main target is what
+# the user explicitly defines in a Jamfile. It is possible to have several
+# definitions for a main target, for example to have different lists of sources
+# for different platforms. So, main targets keep a list of alternatives.
+#
+# Each alternative is an instance of 'abstract-target'. When a main target
+# subvariant is defined by some rule, that rule will decide what class to use,
+# create an instance of that class and add it to the list of alternatives for
+# the main target.
+#
+# Rules supplied by the build system will use only targets derived from
+# 'basic-target' class, which will provide some default behaviour. There will be
+# different classes derived from it such as 'make-target', created by the 'make'
+# rule, and 'typed-target', created by rules such as 'exe' and 'lib'.
+
+#
+# +------------------------+
+# |abstract-target |
+# +========================+
+# |name |
+# |project |
+# | |
+# |generate(properties) = 0|
+# +-----------+------------+
+# |
+# ^
+# / \
+# +-+-+
+# |
+# |
+# +------------------------+------+------------------------------+
+# | | |
+# | | |
+# +----------+-----------+ +------+------+ +------+-------+
+# | project-target | | main-target | | basic-target |
+# +======================+ 1 * +=============+ alternatives +==============+
+# | generate(properties) |o-----------+ generate |<>------------->| generate |
+# | main-target | +-------------+ | construct = 0|
+# +----------------------+ +--------------+
+# |
+# ^
+# / \
+# +-+-+
+# |
+# |
+# ...--+----------------+------------------+----------------+---+
+# | | | |
+# | | | |
+# ... ---+-----+ +------+-------+ +------+------+ +--------+-----+
+# | | typed-target | | make-target | | stage-target |
+# . +==============+ +=============+ +==============+
+# . | construct | | construct | | construct |
+# +--------------+ +-------------+ +--------------+
+
+import assert ;
+import "class" : new ;
+import errors ;
+import feature ;
+import indirect ;
+import path ;
+import property ;
+import property-set ;
+import sequence ;
+import set ;
+import toolset ;
+import build-request ;
+
+
+# Base class for all abstract targets.
+#
+class abstract-target
+{
+ import project ;
+ import assert ;
+ import "class" ;
+ import errors ;
+
+ rule __init__ ( name # Name of the target in Jamfile.
+ : project-target # The project target to which this one belongs.
+ )
+ {
+ # Note: it might seem that we don't need either name or project at all.
+ # However, there are places where we really need it. One example is
+ # error messages which should name problematic targets. Another is
+ # setting correct paths for sources and generated files.
+
+ self.name = $(name) ;
+ self.project = $(project-target) ;
+ self.location = [ errors.nearest-user-location ] ;
+ }
+
+ # Returns the name of this target.
+ rule name ( )
+ {
+ return $(self.name) ;
+ }
+
+ # Returns the project for this target.
+ rule project ( )
+ {
+ return $(self.project) ;
+ }
+
+ # Return the location where the target was declared.
+ rule location ( )
+ {
+ return $(self.location) ;
+ }
+
+ # Returns a user-readable name for this target.
+ rule full-name ( )
+ {
+ local location = [ $(self.project).get location ] ;
+ return $(location)/$(self.name) ;
+ }
+
+ # Generates virtual targets for this abstract target using the specified
+ # properties, unless a different value of some feature is required by the
+ # target.
+ # On success, returns:
+ # - a property-set with the usage requirements to be applied to dependants
+ # - a list of produced virtual targets, which may be empty.
+ # If 'property-set' is empty, performs the default build of this target, in
+ # a way specific to the derived class.
+ #
+ rule generate ( property-set )
+ {
+ errors.error "method should be defined in derived classes" ;
+ }
+
+ rule rename ( new-name )
+ {
+ self.name = $(new-name) ;
+ }
+}
+
+
+if --debug-building in [ modules.peek : ARGV ]
+{
+ modules.poke : .debug-building : true ;
+}
+
+
+rule indent ( )
+{
+ return $(.indent:J="") ;
+}
+
+
+rule increase-indent ( )
+{
+ .indent += " " ;
+}
+
+
+rule decrease-indent ( )
+{
+ .indent = $(.indent[2-]) ;
+}
+
+
+# Project target class (derived from 'abstract-target').
+#
+# This class has the following responsibilities:
+# - Maintaining a list of main targets in this project and building them.
+#
+# Main targets are constructed in two stages:
+# - When Jamfile is read, a number of calls to 'add-alternative' is made. At
+# that time, alternatives can also be renamed to account for inline targets.
+# - The first time 'main-target' or 'has-main-target' rule is called, all
+# alternatives are enumerated and main targets are created.
+#
+class project-target : abstract-target
+{
+ import project ;
+ import targets ;
+ import path ;
+ import print ;
+ import property-set ;
+ import set ;
+ import sequence ;
+ import "class" : new ;
+ import errors ;
+
+ rule __init__ ( name : project-module parent-project ?
+ : requirements * : default-build * )
+ {
+ abstract-target.__init__ $(name) : $(__name__) ;
+
+ self.project-module = $(project-module) ;
+ self.location = [ project.attribute $(project-module) location ] ;
+ self.requirements = $(requirements) ;
+ self.default-build = $(default-build) ;
+
+ if $(parent-project)
+ {
+ inherit $(parent-project) ;
+ }
+ }
+
+ # This is needed only by the 'make' rule. Need to find the way to make
+ # 'make' work without this method.
+ #
+ rule project-module ( )
+ {
+ return $(self.project-module) ;
+ }
+
+ rule get ( attribute )
+ {
+ return [ project.attribute $(self.project-module) $(attribute) ] ;
+ }
+
+ rule build-dir ( )
+ {
+ if ! $(self.build-dir)
+ {
+ self.build-dir = [ get build-dir ] ;
+ if ! $(self.build-dir)
+ {
+ self.build-dir = [ path.join [ $(self.project).get location ]
+ bin ] ;
+ }
+ }
+ return $(self.build-dir) ;
+ }
+
+ # Generates all possible targets contained in this project.
+ #
+ rule generate ( property-set * )
+ {
+ if [ modules.peek : .debug-building ]
+ {
+ ECHO [ targets.indent ] "building project" [ name ] " ('$(__name__)') with" [ $(property-set).raw ] ;
+ targets.increase-indent ;
+ }
+
+ local usage-requirements = [ property-set.empty ] ;
+ local targets ;
+
+ for local t in [ targets-to-build ]
+ {
+ local g = [ $(t).generate $(property-set) ] ;
+ usage-requirements = [ $(usage-requirements).add $(g[1]) ] ;
+ targets += $(g[2-]) ;
+ }
+ targets.decrease-indent ;
+ return $(usage-requirements) [ sequence.unique $(targets) ] ;
+ }
+
+ # Computes and returns a list of abstract-target instances which must be
+ # built when this project is built.
+ #
+ rule targets-to-build ( )
+ {
+ local result ;
+
+ if ! $(self.built-main-targets)
+ {
+ build-main-targets ;
+ }
+
+ # Collect all main targets here, except for "explicit" ones.
+ for local t in $(self.main-targets)
+ {
+ if ! [ $(t).name ] in $(self.explicit-targets)
+ {
+ result += $(t) ;
+ }
+ }
+
+ # Collect all projects referenced via "projects-to-build" attribute.
+ local self-location = [ get location ] ;
+ for local pn in [ get projects-to-build ]
+ {
+ result += [ find $(pn)/ ] ;
+ }
+
+ return $(result) ;
+ }
+
+ # Add 'target' to the list of targets in this project that should be build
+ # only by explicit request
+ #
+ rule mark-target-as-explicit ( target-name * )
+ {
+ # Record the name of the target, not instance, since this rule is called
+ # before main target instances are created.
+ self.explicit-targets += $(target-name) ;
+ }
+
+ rule mark-target-as-always ( target-name * )
+ {
+ # Record the name of the target, not instance, since this rule is called
+ # before main target instances are created.
+ self.always-targets += $(target-name) ;
+ }
+
+ # Add new target alternative
+ #
+ rule add-alternative ( target-instance )
+ {
+ if $(self.built-main-targets)
+ {
+ errors.error add-alternative called when main targets are already
+ created. : in project [ full-name ] ;
+ }
+ self.alternatives += $(target-instance) ;
+ }
+
+ # Returns a 'main-target' class instance corresponding to 'name'.
+ #
+ rule main-target ( name )
+ {
+ if ! $(self.built-main-targets)
+ {
+ build-main-targets ;
+ }
+ return $(self.main-target.$(name)) ;
+ }
+
+ # Returns whether a main target with the specified name exists.
+ #
+ rule has-main-target ( name )
+ {
+ if ! $(self.built-main-targets)
+ {
+ build-main-targets ;
+ }
+
+ if $(self.main-target.$(name))
+ {
+ return true ;
+ }
+ }
+
+ # Worker function for the find rule not implementing any caching and simply
+ # returning nothing in case the target can not be found.
+ #
+ rule find-really ( id )
+ {
+ local result ;
+ local current-location = [ get location ] ;
+
+ local split = [ MATCH (.*)//(.*) : $(id) ] ;
+ local project-part = $(split[1]) ;
+ local target-part = $(split[2]) ;
+
+ local extra-error-message ;
+ if $(project-part)
+ {
+ # There is an explicitly specified project part in id. Looks up the
+ # project and passes the request to it.
+ local pm = [ project.find $(project-part) : $(current-location) ] ;
+ if $(pm)
+ {
+ project-target = [ project.target $(pm) ] ;
+ result = [ $(project-target).find $(target-part) : no-error ] ;
+ }
+ else
+ {
+ # TODO: This extra error message will not get displayed most
+ # likely due to some buggy refactoring. Refactor the code so the
+ # message gets diplayed again.
+ extra-error-message = error: could not find project
+ '$(project-part)' ;
+ }
+ }
+ else
+ {
+ # Interpret target-name as name of main target. Need to do this
+ # before checking for file. Consider the following scenario with a
+ # toolset not modifying its executable's names, e.g. gcc on
+ # Unix-like platforms:
+ #
+ # exe test : test.cpp ;
+ # install s : test : <location>. ;
+ #
+ # After the first build we would have a target named 'test' in the
+ # Jamfile and a file named 'test' on the disk. We need the target to
+ # override the file.
+ result = [ main-target $(id) ] ;
+
+ # Interpret id as an existing file reference.
+ if ! $(result)
+ {
+ result = [ new file-reference [ path.make $(id) ] :
+ $(self.project) ] ;
+ if ! [ $(result).exists ]
+ {
+ result = ;
+ }
+ }
+
+ # Interpret id as project-id.
+ if ! $(result)
+ {
+ local project-module = [ project.find $(id) :
+ $(current-location) ] ;
+ if $(project-module)
+ {
+ result = [ project.target $(project-module) ] ;
+ }
+ }
+ }
+
+ return $(result) ;
+ }
+
+ # Find and return the target with the specified id, treated relative to
+ # self. Id may specify either a target or a file name with the target taking
+ # priority. May report an error or return nothing if the target is not found
+ # depending on the 'no-error' parameter.
+ #
+ rule find ( id : no-error ? )
+ {
+ local v = $(.id.$(id)) ;
+ if ! $(v)
+ {
+ v = [ find-really $(id) ] ;
+ if ! $(v)
+ {
+ v = none ;
+ }
+ .id.$(id) = $(v) ;
+ }
+
+ if $(v) != none
+ {
+ return $(v) ;
+ }
+ else
+ {
+ if ! $(no-error)
+ {
+ local current-location = [ get location ] ;
+ ECHO "error: Unable to find file or target named" ;
+ ECHO "error: '$(id)'" ;
+ ECHO "error: referred from project at" ;
+ ECHO "error: '$(current-location)'" ;
+ ECHO $(extra-error-message) ;
+ EXIT ;
+ }
+ }
+ }
+
+ rule build-main-targets ( )
+ {
+ self.built-main-targets = true ;
+ for local a in $(self.alternatives)
+ {
+ local name = [ $(a).name ] ;
+ local target = $(self.main-target.$(name)) ;
+ if ! $(target)
+ {
+ local t = [ new main-target $(name) : $(self.project) ] ;
+ self.main-target.$(name) = $(t) ;
+ self.main-targets += $(t) ;
+ target = $(self.main-target.$(name)) ;
+ }
+
+ if $(name) in $(self.always-targets)
+ {
+ $(a).always ;
+ }
+
+ $(target).add-alternative $(a) ;
+ }
+ }
+
+ # Accessor, add a constant.
+ #
+ rule add-constant (
+ name # Variable name of the constant.
+ : value + # Value of the constant.
+ : type ? # Optional type of value.
+ )
+ {
+ switch $(type)
+ {
+ case path :
+ local r ;
+ for local v in $(value)
+ {
+ local l = $(self.location) ;
+ if ! $(l)
+ {
+ # Project corresponding to config files do not have
+ # 'location' attribute, but do have source location.
+ # It might be more reasonable to make every project have
+ # a location and use some other approach to prevent buildable
+ # targets in config files, but that's for later.
+ l = [ get source-location ] ;
+ }
+ v = [ path.root [ path.make $(v) ] $(l) ] ;
+ # Now make the value absolute path.
+ v = [ path.root $(v) [ path.pwd ] ] ;
+ # Constants should be in platform-native form.
+ v = [ path.native $(v) ] ;
+ r += $(v) ;
+ }
+ value = $(r) ;
+ }
+ if ! $(name) in $(self.constants)
+ {
+ self.constants += $(name) ;
+ }
+ self.constant.$(name) = $(value) ;
+ # Inject the constant in the scope of the Jamroot module.
+ modules.poke $(self.project-module) : $(name) : $(value) ;
+ }
+
+ rule inherit ( parent )
+ {
+ for local c in [ modules.peek $(parent) : self.constants ]
+ {
+ # No need to pass the type. Path constants were converted to
+ # absolute paths already by parent.
+ add-constant $(c)
+ : [ modules.peek $(parent) : self.constant.$(c) ] ;
+ }
+
+ # Import rules from parent.
+ local this-module = [ project-module ] ;
+ local parent-module = [ $(parent).project-module ] ;
+ # Do not import rules coming from 'project-rules' as they must be
+ # imported localized.
+ local user-rules = [ set.difference
+ [ RULENAMES $(parent-module) ] :
+ [ RULENAMES project-rules ] ] ;
+ IMPORT $(parent-module) : $(user-rules) : $(this-module) : $(user-rules) ;
+ EXPORT $(this-module) : $(user-rules) ;
+ }
+}
+
+
+# Helper rules to detect cycles in main target references.
+#
+local rule start-building ( main-target-instance )
+{
+ if $(main-target-instance) in $(.targets-being-built)
+ {
+ local names ;
+ for local t in $(.targets-being-built) $(main-target-instance)
+ {
+ names += [ $(t).full-name ] ;
+ }
+
+ errors.error "Recursion in main target references"
+ : "the following target are being built currently:"
+ : $(names) ;
+ }
+ .targets-being-built += $(main-target-instance) ;
+}
+
+
+local rule end-building ( main-target-instance )
+{
+ .targets-being-built = $(.targets-being-built[1--2]) ;
+}
+
+
+# A named top-level target in Jamfile.
+#
+class main-target : abstract-target
+{
+ import assert ;
+ import errors ;
+ import feature ;
+ import print ;
+ import property-set ;
+ import sequence ;
+ import targets : start-building end-building ;
+
+ rule __init__ ( name : project )
+ {
+ abstract-target.__init__ $(name) : $(project) ;
+ }
+
+ # Add a new alternative for this target
+ rule add-alternative ( target )
+ {
+ local d = [ $(target).default-build ] ;
+ if $(self.alternatives) && ( $(self.default-build) != $(d) )
+ {
+ errors.error "default build must be identical in all alternatives"
+ : "main target is" [ full-name ]
+ : "with" [ $(d).raw ]
+ : "differing from previous default build" [ $(self.default-build).raw ] ;
+ }
+ else
+ {
+ self.default-build = $(d) ;
+ }
+ self.alternatives += $(target) ;
+ }
+
+ # Returns the best viable alternative for this property-set. See the
+ # documentation for selection rules.
+ #
+ local rule select-alternatives ( property-set debug ? )
+ {
+ # When selecting alternatives we have to consider defaults, for example:
+ # lib l : l.cpp : <variant>debug ;
+ # lib l : l_opt.cpp : <variant>release ;
+ # won't work unless we add default value <variant>debug.
+ property-set = [ $(p).add-defaults ] ;
+
+ # The algorithm: we keep the current best viable alternative. When we've
+ # got a new best viable alternative, we compare it with the current one.
+
+ local best ;
+ local best-properties ;
+
+ if $(self.alternatives[2-])
+ {
+ local bad ;
+ local worklist = $(self.alternatives) ;
+ while $(worklist) && ! $(bad)
+ {
+ local v = $(worklist[1]) ;
+ local properties = [ $(v).match $(property-set) $(debug) ] ;
+
+ if $(properties) != no-match
+ {
+ if ! $(best)
+ {
+ best = $(v) ;
+ best-properties = $(properties) ;
+ }
+ else
+ {
+ if $(properties) = $(best-properties)
+ {
+ bad = true ;
+ }
+ else if $(properties) in $(best-properties)
+ {
+ # Do nothing, this alternative is worse
+ }
+ else if $(best-properties) in $(properties)
+ {
+ best = $(v) ;
+ best-properties = $(properties) ;
+ }
+ else
+ {
+ bad = true ;
+ }
+ }
+ }
+ worklist = $(worklist[2-]) ;
+ }
+ if ! $(bad)
+ {
+ return $(best) ;
+ }
+ }
+ else
+ {
+ return $(self.alternatives) ;
+ }
+ }
+
+ rule apply-default-build ( property-set )
+ {
+ return [ targets.apply-default-build $(property-set)
+ : $(self.default-build) ] ;
+ }
+
+ # Select an alternative for this main target, by finding all alternatives
+ # which requirements are satisfied by 'properties' and picking the one with
+ # the longest requirements set. Returns the result of calling 'generate' on
+ # that alternative.
+ #
+ rule generate ( property-set )
+ {
+ start-building $(__name__) ;
+
+ # We want composite properties in build request act as if all the
+ # properties it expands too are explicitly specified.
+ property-set = [ $(property-set).expand ] ;
+
+ local all-property-sets = [ apply-default-build $(property-set) ] ;
+ local usage-requirements = [ property-set.empty ] ;
+ local result ;
+ for local p in $(all-property-sets)
+ {
+ local r = [ generate-really $(p) ] ;
+ if $(r)
+ {
+ usage-requirements = [ $(usage-requirements).add $(r[1]) ] ;
+ result += $(r[2-]) ;
+ }
+ }
+ end-building $(__name__) ;
+ return $(usage-requirements) [ sequence.unique $(result) ] ;
+ }
+
+ # Generates the main target with the given property set and returns a list
+ # which first element is property-set object containing usage-requirements
+ # of generated target and with generated virtual target in other elements.
+ # It is possible that no targets are generated.
+ #
+ local rule generate-really ( property-set )
+ {
+ local best-alternatives = [ select-alternatives $(property-set) ] ;
+ if ! $(best-alternatives)
+ {
+ ECHO "error: No best alternative for" [ full-name ] ;
+ select-alternatives $(property-set) debug ;
+ return [ property-set.empty ] ;
+ }
+ else
+ {
+ # Now return virtual targets for the only alternative.
+ return [ $(best-alternatives).generate $(property-set) ] ;
+ }
+ }
+
+ rule rename ( new-name )
+ {
+ abstract-target.rename $(new-name) ;
+ for local a in $(self.alternatives)
+ {
+ $(a).rename $(new-name) ;
+ }
+ }
+}
+
+
+# Abstract target refering to a source file. This is an artificial entity
+# allowing sources to a target to be represented using a list of abstract target
+# instances.
+#
+class file-reference : abstract-target
+{
+ import virtual-target ;
+ import property-set ;
+ import path ;
+
+ rule __init__ ( file : project )
+ {
+ abstract-target.__init__ $(file) : $(project) ;
+ }
+
+ rule generate ( properties )
+ {
+ return [ property-set.empty ] [ virtual-target.from-file $(self.name) :
+ [ location ] : $(self.project) ] ;
+ }
+
+ # Returns true if the referred file really exists.
+ rule exists ( )
+ {
+ location ;
+ return $(self.file-path) ;
+ }
+
+ # Returns the location of target. Needed by 'testing.jam'.
+ rule location ( )
+ {
+ if ! $(self.file-location)
+ {
+ local source-location = [ $(self.project).get source-location ] ;
+ for local src-dir in $(source-location)
+ {
+ if ! $(self.file-location)
+ {
+ local location = [ path.root $(self.name) $(src-dir) ] ;
+ if [ CHECK_IF_FILE [ path.native $(location) ] ]
+ {
+ self.file-location = $(src-dir) ;
+ self.file-path = $(location) ;
+ }
+ }
+ }
+ }
+ return $(self.file-location) ;
+ }
+}
+
+
+# Given a target-reference, made in context of 'project', returns the
+# abstract-target instance that is referred to, as well as properties explicitly
+# specified for this reference.
+#
+rule resolve-reference ( target-reference : project )
+{
+ # Separate target name from properties override.
+ local split = [ MATCH "^([^<]*)(/(<.*))?$" : $(target-reference) ] ;
+ local id = $(split[1]) ;
+ local sproperties = ;
+ if $(split[3])
+ {
+ sproperties = [ property.make [ feature.split $(split[3]) ] ] ;
+ sproperties = [ feature.expand-composites $(sproperties) ] ;
+ }
+
+ # Find the target.
+ local target = [ $(project).find $(id) ] ;
+
+ return $(target) [ property-set.create $(sproperties) ] ;
+}
+
+
+# Attempts to generate the target given by target reference, which can refer
+# both to a main target or to a file. Returns a list consisting of
+# - usage requirements
+# - generated virtual targets, if any
+#
+rule generate-from-reference (
+ target-reference # Target reference.
+ : project # Project where the reference is made.
+ : property-set # Properties of the main target that makes the reference.
+)
+{
+ local r = [ resolve-reference $(target-reference) : $(project) ] ;
+ local target = $(r[1]) ;
+ local sproperties = $(r[2]) ;
+
+ # Take properties which should be propagated and refine them with
+ # source-specific requirements.
+ local propagated = [ $(property-set).propagated ] ;
+ local rproperties = [ $(propagated).refine $(sproperties) ] ;
+ if $(rproperties[1]) = "@error"
+ {
+ errors.error
+ "When building" [ full-name ] " with properties " $(properties) :
+ "Invalid properties specified for " $(source) ":"
+ $(rproperties[2-]) ;
+ }
+ return [ $(target).generate $(rproperties) ] ;
+}
+
+rule apply-default-build ( property-set : default-build )
+{
+ # 1. First, see what properties from default-build are already present
+ # in property-set.
+
+ local raw = [ $(property-set).raw ] ;
+ local specified-features = $(raw:G) ;
+
+ local defaults-to-apply ;
+ for local d in [ $(default-build).raw ]
+ {
+ if ! $(d:G) in $(specified-features)
+ {
+ defaults-to-apply += $(d) ;
+ }
+ }
+
+ # 2. If there are any defaults to be applied, form a new build request.
+ # Pass it through to 'expand-no-defaults' since default-build might
+ # contain "release debug" resulting in two property-sets.
+ local result ;
+ if $(defaults-to-apply)
+ {
+ properties = [
+ build-request.expand-no-defaults
+
+ # We have to compress subproperties here to prevent property
+ # lists like:
+ #
+ # <toolset>msvc <toolset-msvc:version>7.1 <threading>multi
+ #
+ # from being expanded into:
+ #
+ # <toolset-msvc:version>7.1/<threading>multi
+ # <toolset>msvc/<toolset-msvc:version>7.1/<threading>multi
+ #
+ # due to a cross-product property combination. That may be an
+ # indication that build-request.expand-no-defaults is the wrong
+ # rule to use here.
+ [ feature.compress-subproperties $(raw) ]
+ $(defaults-to-apply)
+ ] ;
+
+ if $(properties)
+ {
+ for local p in $(properties)
+ {
+ result += [ property-set.create
+ [ feature.expand [ feature.split $(p) ] ] ] ;
+ }
+ }
+ else
+ {
+ result = [ property-set.empty ] ;
+ }
+ }
+ else
+ {
+ result = $(property-set) ;
+ }
+ return $(result) ;
+}
+
+
+# Given a build request and requirements, return properties common to dependency
+# build request and target requirements.
+#
+# TODO: Document exactly what 'common properties' are, whether they should
+# include default property values, whether they should contain any conditional
+# properties or should those be already processed, etc. See whether there are
+# any differences between use cases with empty and non-empty build-request as
+# well as with requirements containing and those not containing any non-free
+# features.
+#
+rule common-properties ( build-request requirements )
+{
+ # For optimization, we add free requirements directly, without using a
+ # complex algorithm. This gives the complex algorithm a better chance of
+ # caching results.
+ local free = [ $(requirements).free ] ;
+ local non-free = [ property-set.create [ $(requirements).base ]
+ [ $(requirements).incidental ] ] ;
+
+ local key = .rp.$(build-request)-$(non-free) ;
+ if ! $($(key))
+ {
+ $(key) = [ common-properties2 $(build-request) $(non-free) ] ;
+ }
+ result = [ $($(key)).add-raw $(free) ] ;
+}
+
+
+# Given a 'context' -- a set of already present properties, and 'requirements',
+# decide which extra properties should be applied to 'context'. For conditional
+# requirements, this means evaluating the condition. For indirect conditional
+# requirements, this means calling a rule. Ordinary requirements are always
+# applied.
+#
+# Handles the situation where evaluating one conditional requirement affects
+# conditions of another conditional requirements, such as:
+# <toolset>gcc:<variant>release <variant>release:<define>RELEASE
+#
+# If 'what' is 'refined' returns context refined with new requirements. If
+# 'what' is 'added' returns just the requirements to be applied.
+#
+rule evaluate-requirements ( requirements : context : what )
+{
+ # Apply non-conditional requirements. It is possible that further
+ # conditional requirement change a value set by non-conditional
+ # requirements. For example:
+ #
+ # exe a : a.cpp : <threading>single <toolset>foo:<threading>multi ;
+ #
+ # I am not sure if this should be an error, or not, especially given that
+ #
+ # <threading>single
+ #
+ # might come from project's requirements.
+
+ local unconditional = [ feature.expand [ $(requirements).non-conditional ] ] ;
+
+ local raw = [ $(context).raw ] ;
+ raw = [ property.refine $(raw) : $(unconditional) ] ;
+
+ # We have collected properties that surely must be present in common
+ # properties. We now try to figure out what other properties should be added
+ # in order to satisfy rules (4)-(6) from the docs.
+
+ local conditionals = [ $(requirements).conditional ] ;
+ # The 'count' variable has one element for each conditional feature and for
+ # each occurrence of '<indirect-conditional>' feature. It is used as a loop
+ # counter: for each iteration of the loop before we remove one element and
+ # the property set should stabilize before we are done. It is assumed that
+ # #conditionals iterations should be enough for properties to propagate
+ # along conditions in any direction.
+ local count = $(conditionals)
+ [ $(requirements).get <conditional> ]
+ and-once-more ;
+
+ local added-requirements ;
+
+ local current = $(raw) ;
+
+ # It is assumed that ordinary conditional requirements can not add
+ # <conditional> properties (a.k.a. indirect conditional properties), and
+ # that rules referred to by <conditional> properties can not add new
+ # <conditional> properties. So the list of indirect conditionals does not
+ # change.
+ local indirect = [ $(requirements).get <conditional> ] ;
+ indirect = [ MATCH ^@(.*) : $(indirect) ] ;
+
+ local ok ;
+ while $(count)
+ {
+ # Evaluate conditionals in context of current properties.
+ local e = [ property.evaluate-conditionals-in-context $(conditionals)
+ : $(current) ] ;
+
+ # Evaluate indirect conditionals.
+ for local i in $(indirect)
+ {
+ e += [ indirect.call $(i) $(current) ] ;
+ }
+
+ if $(e) = $(added-requirements)
+ {
+ # If we got the same result, we have found the final properties.
+ count = ;
+ ok = true ;
+ }
+ else
+ {
+ # Oops, conditional evaluation results have changed. Also 'current'
+ # contains leftovers from a previous evaluation. Recompute 'current'
+ # using initial properties and conditional requirements.
+ added-requirements = $(e) ;
+ current = [ property.refine $(raw) : [ feature.expand $(e) ] ] ;
+ }
+ count = $(count[2-]) ;
+ }
+ if ! $(ok)
+ {
+ errors.error "Can not evaluate conditional properties " $(conditionals) ;
+ }
+
+ if $(what) = added
+ {
+ return [ property-set.create $(unconditional) $(added-requirements) ] ;
+ }
+ else if $(what) = refined
+ {
+ return [ property-set.create $(current) ] ;
+ }
+ else
+ {
+ errors.error "Invalid value of the 'what' parameter." ;
+ }
+}
+
+
+rule common-properties2 ( build-request requirements )
+{
+ # This guarantees that default properties are present in the result, unless
+ # they are overriden by some requirement. FIXME: There is possibility that
+ # we have added <foo>bar, which is composite and expands to <foo2>bar2, but
+ # default value of <foo2> is not bar2, in which case it is not clear what to
+ # do.
+ #
+ build-request = [ $(build-request).add-defaults ] ;
+ # Features added by 'add-default' can be composite and expand to features
+ # without default values -- so they are not added yet. It could be clearer/
+ # /faster to expand only newly added properties but that is not critical.
+ build-request = [ $(build-request).expand ] ;
+
+ return [ evaluate-requirements $(requirements) : $(build-request) :
+ refined ] ;
+}
+
+rule push-target ( target )
+{
+ .targets = $(target) $(.targets) ;
+}
+
+rule pop-target ( )
+{
+ .targets = $(.targets[2-]) ;
+}
+
+# Return the metatarget that is currently being generated.
+rule current ( )
+{
+ return $(.targets[1]) ;
+}
+
+
+# Implements the most standard way of constructing main target alternative from
+# sources. Allows sources to be either file or other main target and handles
+# generation of those dependency targets.
+#
+class basic-target : abstract-target
+{
+ import build-request ;
+ import build-system ;
+ import "class" : new ;
+ import errors ;
+ import feature ;
+ import property ;
+ import property-set ;
+ import sequence ;
+ import set ;
+ import targets ;
+ import virtual-target ;
+
+ rule __init__ ( name : project : sources * : requirements *
+ : default-build * : usage-requirements * )
+ {
+ abstract-target.__init__ $(name) : $(project) ;
+
+ self.sources = $(sources) ;
+ if ! $(requirements) {
+ requirements = [ property-set.empty ] ;
+ }
+ self.requirements = $(requirements) ;
+ if ! $(default-build)
+ {
+ default-build = [ property-set.empty ] ;
+ }
+ self.default-build = $(default-build) ;
+ if ! $(usage-requirements)
+ {
+ usage-requirements = [ property-set.empty ] ;
+ }
+ self.usage-requirements = $(usage-requirements) ;
+
+ if $(sources:G)
+ {
+ errors.user-error properties found in the 'sources' parameter for
+ [ full-name ] ;
+ }
+ }
+
+ rule always ( )
+ {
+ self.always = 1 ;
+ }
+
+ # Returns the list of abstract-targets which are used as sources. The extra
+ # properties specified for sources are not represented. The only user for
+ # this rule at the moment is the "--dump-tests" feature of the test system.
+ #
+ rule sources ( )
+ {
+ if ! $(self.source-targets)
+ {
+ for local s in $(self.sources)
+ {
+ self.source-targets +=
+ [ targets.resolve-reference $(s) : $(self.project) ] ;
+ }
+ }
+ return $(self.source-targets) ;
+ }
+
+ rule requirements ( )
+ {
+ return $(self.requirements) ;
+ }
+
+ rule default-build ( )
+ {
+ return $(self.default-build) ;
+ }
+
+ # Returns the alternative condition for this alternative, if the condition
+ # is satisfied by 'property-set'.
+ #
+ rule match ( property-set debug ? )
+ {
+ # The condition is composed of all base non-conditional properties. It
+ # is not clear if we should expand 'self.requirements' or not. For one
+ # thing, it would be nice to be able to put
+ # <toolset>msvc-6.0
+ # in requirements. On the other hand, if we have <variant>release as a
+ # condition it does not make sense to require <optimization>full to be
+ # in the build request just to select this variant.
+ local bcondition = [ $(self.requirements).base ] ;
+ local ccondition = [ $(self.requirements).conditional ] ;
+ local condition = [ set.difference $(bcondition) : $(ccondition) ] ;
+ if $(debug)
+ {
+ ECHO " next alternative: required properties:" $(condition:E=(empty)) ;
+ }
+
+ if $(condition) in [ $(property-set).raw ]
+ {
+ if $(debug)
+ {
+ ECHO " matched" ;
+ }
+ return $(condition) ;
+ }
+ else
+ {
+ if $(debug)
+ {
+ ECHO " not matched" ;
+ }
+ return no-match ;
+ }
+ }
+
+ # Takes a target reference, which might be either target id or a dependency
+ # property, and generates that target using 'property-set' as build request.
+ #
+ # The results are added to the variable called 'result-var'. Usage
+ # requirements are added to the variable called 'usage-requirements-var'.
+ #
+ rule generate-dependencies ( dependencies * : property-set
+ : result-var usage-requirements-var )
+ {
+ for local dependency in $(dependencies)
+ {
+ local grist = $(dependency:G) ;
+ local id = $(dependency:G=) ;
+
+ local result = [ targets.generate-from-reference $(id) :
+ $(self.project) : $(property-set) ] ;
+
+ $(result-var) += $(result[2-]:G=$(grist)) ;
+ $(usage-requirements-var) += [ $(result[1]).raw ] ;
+ }
+ }
+
+ # Determines final build properties, generates sources, and calls
+ # 'construct'. This method should not be overridden.
+ #
+ rule generate ( property-set )
+ {
+ if [ modules.peek : .debug-building ]
+ {
+ ECHO ;
+ local fn = [ full-name ] ;
+ ECHO [ targets.indent ] "Building target '$(fn)'" ;
+ targets.increase-indent ;
+ ECHO [ targets.indent ] "Build request: " $(property-set) [ $(property-set).raw ] ;
+ local cf = [ build-system.command-line-free-features ] ;
+ ECHO [ targets.indent ] "Command line free features: " [ $(cf).raw ] ;
+ ECHO [ targets.indent ] "Target requirements: " [ $(self.requirements).raw ] ;
+ }
+ targets.push-target $(__name__) ;
+
+ if ! $(self.generated.$(property-set))
+ {
+ # Apply free features from the command line. If user said
+ # define=FOO
+ # he most likely wants this define to be set for all compiles.
+ property-set = [ $(property-set).refine
+ [ build-system.command-line-free-features ] ] ;
+ local rproperties = [ targets.common-properties $(property-set)
+ $(self.requirements) ] ;
+
+ if [ modules.peek : .debug-building ]
+ {
+ ECHO ;
+ ECHO [ targets.indent ] "Common properties: " [ $(rproperties).raw ] ;
+ }
+
+ if ( $(rproperties[1]) != "@error" ) && ( [ $(rproperties).get
+ <build> ] != no )
+ {
+ local source-targets ;
+ local properties = [ $(rproperties).non-dependency ] ;
+ local usage-requirements ;
+
+ generate-dependencies [ $(rproperties).dependency ] :
+ $(rproperties) : properties usage-requirements ;
+
+ generate-dependencies $(self.sources) : $(rproperties) :
+ source-targets usage-requirements ;
+
+ if [ modules.peek : .debug-building ]
+ {
+ ECHO ;
+ ECHO [ targets.indent ] "Usage requirements for"
+ $(self.name)": " $(usage-requirements) ;
+ }
+
+ rproperties = [ property-set.create $(properties)
+ $(usage-requirements) ] ;
+ usage-requirements = [ property-set.create $(usage-requirements) ] ;
+
+ if [ modules.peek : .debug-building ]
+ {
+ ECHO [ targets.indent ] "Build properties: "
+ [ $(rproperties).raw ] ;
+ }
+
+ local extra = [ $(rproperties).get <source> ] ;
+ source-targets += $(extra:G=) ;
+ # We might get duplicate sources, for example if we link to two
+ # libraries having the same <library> usage requirement.
+ # Use stable sort, since for some targets the order is
+ # important. E.g. RUN_PY target need python source to come
+ # first.
+ source-targets = [ sequence.unique $(source-targets) : stable ] ;
+
+ local result = [ construct $(self.name) : $(source-targets) :
+ $(rproperties) ] ;
+
+ if $(result)
+ {
+ local gur = $(result[1]) ;
+ result = $(result[2-]) ;
+
+ if $(self.always)
+ {
+ for local t in $(result)
+ {
+ $(t).always ;
+ }
+ }
+
+ local s = [ create-subvariant $(result)
+ : [ virtual-target.recent-targets ]
+ : $(property-set) : $(source-targets)
+ : $(rproperties) : $(usage-requirements) ] ;
+ virtual-target.clear-recent-targets ;
+
+ local ur = [ compute-usage-requirements $(s) ] ;
+ ur = [ $(ur).add $(gur) ] ;
+ $(s).set-usage-requirements $(ur) ;
+ if [ modules.peek : .debug-building ]
+ {
+ ECHO [ targets.indent ] "Usage requirements from"
+ $(self.name)": " [ $(ur).raw ] ;
+ }
+
+ self.generated.$(property-set) = $(ur) $(result) ;
+ }
+ }
+ else
+ {
+ if $(rproperties[1]) = "@error"
+ {
+ ECHO [ targets.indent ] "Skipping build of:" [ full-name ]
+ "cannot compute common properties" ;
+ }
+ else if [ $(rproperties).get <build> ] = no
+ {
+ # If we just see <build>no, we cannot produce any reasonable
+ # diagnostics. The code that adds this property is expected
+ # to explain why a target is not built, for example using
+ # the configure.log-component-configuration function.
+ }
+ else
+ {
+ ECHO [ targets.indent ] "Skipping build of: " [ full-name ]
+ " unknown reason" ;
+ }
+
+ # We are here either because there has been an error computing
+ # properties or there is <build>no in properties. In the latter
+ # case we do not want any diagnostic. In the former case, we
+ # need diagnostics. FIXME
+
+ # If this target fails to build, add <build>no to properties to
+ # cause any parent target to fail to build. Except that it
+ # - does not work now, since we check for <build>no only in
+ # common properties, but not in properties that came from
+ # dependencies
+ # - it is not clear if that is a good idea anyway. The alias
+ # target, for example, should not fail to build if a
+ # dependency fails.
+ self.generated.$(property-set) = [ property-set.create <build>no ] ;
+ }
+ }
+ else
+ {
+ if [ modules.peek : .debug-building ]
+ {
+ ECHO [ targets.indent ] "Already built" ;
+ local ur = $(self.generated.$(property-set)) ;
+ ur = $(ur[0]) ;
+ targets.increase-indent ;
+ ECHO [ targets.indent ] "Usage requirements from"
+ $(self.name)": " [ $(ur).raw ] ;
+ targets.decrease-indent ;
+ }
+ }
+
+ targets.pop-target ;
+ targets.decrease-indent ;
+ return $(self.generated.$(property-set)) ;
+ }
+
+ # Given the set of generated targets, and refined build properties,
+ # determines and sets appropriate usage requirements on those targets.
+ #
+ rule compute-usage-requirements ( subvariant )
+ {
+ local rproperties = [ $(subvariant).build-properties ] ;
+ xusage-requirements = [ targets.evaluate-requirements
+ $(self.usage-requirements) : $(rproperties) : added ] ;
+
+ # We generate all dependency properties and add them, as well as their
+ # usage requirements, to the result.
+ local extra ;
+ generate-dependencies [ $(xusage-requirements).dependency ] :
+ $(rproperties) : extra extra ;
+
+ local result = [ property-set.create
+ [ $(xusage-requirements).non-dependency ] $(extra) ] ;
+
+ # Propagate usage requirements we got from sources, except for the
+ # <pch-header> and <pch-file> features.
+ #
+ # That feature specifies which pch file to use, and should apply only to
+ # direct dependents. Consider:
+ #
+ # pch pch1 : ...
+ # lib lib1 : ..... pch1 ;
+ # pch pch2 :
+ # lib lib2 : pch2 lib1 ;
+ #
+ # Here, lib2 should not get <pch-header> property from pch1.
+ #
+ # Essentially, when those two features are in usage requirements, they
+ # are propagated only to direct dependents. We might need a more general
+ # mechanism, but for now, only those two features are special.
+ #
+ # TODO - Actually there are more possible candidates like for instance
+ # when listing static library X as a source for another static library.
+ # Then static library X will be added as a <source> property to the
+ # second library's usage requirements but those requirements should last
+ # only up to the first executable or shared library that actually links
+ # to it.
+ local raw = [ $(subvariant).sources-usage-requirements ] ;
+ raw = [ $(raw).raw ] ;
+ raw = [ property.change $(raw) : <pch-header> ] ;
+ raw = [ property.change $(raw) : <pch-file> ] ;
+ return [ $(result).add [ property-set.create $(raw) ] ] ;
+ }
+
+ # Creates new subvariant instances for 'targets'.
+ # 'root-targets' - virtual targets to be returned to dependants
+ # 'all-targets' - virtual targets created while building this main target
+ # 'build-request' - property-set instance with requested build properties
+ #
+ local rule create-subvariant ( root-targets * : all-targets * :
+ build-request : sources * : rproperties : usage-requirements )
+ {
+ for local e in $(root-targets)
+ {
+ $(e).root true ;
+ }
+
+ # Process all virtual targets that will be created if this main target
+ # is created.
+ local s = [ new subvariant $(__name__) : $(build-request) : $(sources) :
+ $(rproperties) : $(usage-requirements) : $(all-targets) ] ;
+ for local v in $(all-targets)
+ {
+ if ! [ $(v).creating-subvariant ]
+ {
+ $(v).creating-subvariant $(s) ;
+ }
+ }
+ return $(s) ;
+ }
+
+ # Constructs virtual targets for this abstract target and the dependency
+ # graph. Returns a usage-requirements property-set and a list of virtual
+ # targets. Should be overriden in derived classes.
+ #
+ rule construct ( name : source-targets * : properties * )
+ {
+ errors.error "method should be defined in derived classes" ;
+ }
+}
+
+
+class typed-target : basic-target
+{
+ import generators ;
+
+ rule __init__ ( name : project : type : sources * : requirements * :
+ default-build * : usage-requirements * )
+ {
+ basic-target.__init__ $(name) : $(project) : $(sources) :
+ $(requirements) : $(default-build) : $(usage-requirements) ;
+
+ self.type = $(type) ;
+ }
+
+ rule type ( )
+ {
+ return $(self.type) ;
+ }
+
+ rule construct ( name : source-targets * : property-set )
+ {
+ local r = [ generators.construct $(self.project) $(name:S=) : $(self.type)
+ : [ property-set.create [ $(property-set).raw ]
+ <main-target-type>$(self.type) ]
+ : $(source-targets) : true ] ;
+ if ! $(r)
+ {
+ ECHO "warn: Unable to construct" [ full-name ] ;
+
+ # Are there any top-level generators for this type/property set.
+ if ! [ generators.find-viable-generators $(self.type)
+ : $(property-set) ]
+ {
+ ECHO "error: no generators were found for type '$(self.type)'" ;
+ ECHO "error: and the requested properties" ;
+ ECHO "error: make sure you've configured the needed tools" ;
+ ECHO "See http://boost.org/boost-build2/doc/html/bbv2/advanced/configuration.html" ;
+ ECHO "To debug this problem, try the --debug-generators option." ;
+ EXIT ;
+ }
+ }
+ return $(r) ;
+ }
+}
+
+
+# Return the list of sources to use, if main target rule is invoked with
+# 'sources'. If there are any objects in 'sources', they are treated as main
+# target instances, and the name of such targets are adjusted to be
+# '<name_of_this_target>__<name_of_source_target>'. Such renaming is disabled if
+# a non-empty value is passed as the 'no-renaming' parameter.
+#
+rule main-target-sources ( sources * : main-target-name : no-renaming ? )
+{
+ local result ;
+ for local t in $(sources)
+ {
+ if [ class.is-instance $(t) ]
+ {
+ local name = [ $(t).name ] ;
+ if ! $(no-renaming)
+ {
+ name = $(main-target-name)__$(name) ;
+ $(t).rename $(name) ;
+ }
+ # Inline targets are not built by default.
+ local p = [ $(t).project ] ;
+ $(p).mark-target-as-explicit $(name) ;
+ result += $(name) ;
+ }
+ else
+ {
+ result += $(t) ;
+ }
+ }
+ return $(result) ;
+}
+
+
+# Returns the requirements to use when declaring a main target, obtained by
+# translating all specified property paths and refining project requirements
+# with the ones specified for the target.
+#
+rule main-target-requirements (
+ specification * # Properties explicitly specified for the main target.
+ : project # Project where the main target is to be declared.
+)
+{
+ specification += [ toolset.requirements ] ;
+
+ local requirements = [ property-set.refine-from-user-input
+ [ $(project).get requirements ] : $(specification) :
+ [ $(project).project-module ] : [ $(project).get location ] ] ;
+ if $(requirements[1]) = "@error"
+ {
+ errors.error "Conflicting requirements for target:" $(requirements) ;
+ }
+ return $(requirements) ;
+}
+
+
+# Returns the usage requirements to use when declaring a main target, which are
+# obtained by translating all specified property paths and adding project's
+# usage requirements.
+#
+rule main-target-usage-requirements (
+ specification * # Use-properties explicitly specified for a main target.
+ : project # Project where the main target is to be declared.
+)
+{
+ local project-usage-requirements = [ $(project).get usage-requirements ] ;
+
+ # We do not use 'refine-from-user-input' because:
+ # - I am not sure if removing parent's usage requirements makes sense
+ # - refining usage requirements is not needed, since usage requirements are
+ # always free.
+ local usage-requirements = [ property-set.create-from-user-input
+ $(specification)
+ : [ $(project).project-module ] [ $(project).get location ] ] ;
+
+ return [ $(project-usage-requirements).add $(usage-requirements) ] ;
+}
+
+
+# Return the default build value to use when declaring a main target, which is
+# obtained by using the specified value if not empty and parent's default build
+# attribute otherwise.
+#
+rule main-target-default-build (
+ specification * # Default build explicitly specified for a main target.
+ : project # Project where the main target is to be declared.
+)
+{
+ local result ;
+ if $(specification)
+ {
+ result = $(specification) ;
+ }
+ else
+ {
+ result = [ $(project).get default-build ] ;
+ }
+ return [ property-set.create-with-validation $(result) ] ;
+}
+
+
+# Registers the specified target as a main target alternative and returns it.
+#
+rule main-target-alternative ( target )
+{
+ local ptarget = [ $(target).project ] ;
+ $(ptarget).add-alternative $(target) ;
+ return $(target) ;
+}
+
+# Creates a new metargets with the specified properties, using 'klass' as
+# the class. The 'name', 'sources',
+# 'requirements', 'default-build' and 'usage-requirements' are assumed to be in
+# the form specified by the user in Jamfile corresponding to 'project'.
+#
+rule create-metatarget ( klass : project : name : sources * : requirements * :
+ default-build * : usage-requirements * )
+{
+ return [
+ targets.main-target-alternative
+ [ new $(klass) $(name) : $(project)
+ : [ targets.main-target-sources $(sources) : $(name) ]
+ : [ targets.main-target-requirements $(requirements) : $(project) ]
+ : [ targets.main-target-default-build $(default-build) : $(project) ]
+ : [ targets.main-target-usage-requirements $(usage-requirements) : $(project) ]
+ ] ] ;
+}
+
+# Creates a typed-target with the specified properties. The 'name', 'sources',
+# 'requirements', 'default-build' and 'usage-requirements' are assumed to be in
+# the form specified by the user in Jamfile corresponding to 'project'.
+#
+rule create-typed-target ( type : project : name : sources * : requirements * :
+ default-build * : usage-requirements * )
+{
+ return [
+ targets.main-target-alternative
+ [ new typed-target $(name) : $(project) : $(type)
+ : [ targets.main-target-sources $(sources) : $(name) ]
+ : [ targets.main-target-requirements $(requirements) : $(project) ]
+ : [ targets.main-target-default-build $(default-build) : $(project) ]
+ : [ targets.main-target-usage-requirements $(usage-requirements) : $(project) ]
+ ] ] ;
+}