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mirror of https://github.com/samba-team/samba.git synced 2024-12-27 03:21:53 +03:00
samba-mirror/buildtools/wafsamba/samba_deps.py
Andrew Tridgell c5d0208aa9 build: fixed handling of full dependencies for --disable-shared
the subsystem dependency loops get quite complex when shared libs are
disabled
2010-04-06 20:27:00 +10:00

823 lines
26 KiB
Python

# Samba automatic dependency handling and project rules
import Build, os, re, Environment
from samba_utils import *
from samba_autoconf import *
@conf
def ADD_GLOBAL_DEPENDENCY(ctx, dep):
'''add a dependency for all binaries and libraries'''
if not 'GLOBAL_DEPENDENCIES' in ctx.env:
ctx.env.GLOBAL_DEPENDENCIES = []
ctx.env.GLOBAL_DEPENDENCIES.append(dep)
def TARGET_ALIAS(bld, target, alias):
'''define an alias for a target name'''
cache = LOCAL_CACHE(bld, 'TARGET_ALIAS')
if alias in cache:
print("Target alias %s already set to %s : newalias %s" % (alias, cache[alias], target))
raise
cache[alias] = target
Build.BuildContext.TARGET_ALIAS = TARGET_ALIAS
def EXPAND_ALIAS(bld, target):
'''expand a target name via an alias'''
aliases = LOCAL_CACHE(bld, 'TARGET_ALIAS')
if target in aliases:
return aliases[target]
return target
Build.BuildContext.EXPAND_ALIAS = EXPAND_ALIAS
def expand_subsystem_deps(bld):
'''expand the reverse dependencies resulting from subsystem
attributes of modules'''
subsystems = LOCAL_CACHE(bld, 'INIT_FUNCTIONS')
aliases = LOCAL_CACHE(bld, 'TARGET_ALIAS')
targets = LOCAL_CACHE(bld, 'TARGET_TYPE')
for s in subsystems:
if s in aliases:
s = aliases[s]
bld.ASSERT(s in targets, "Subsystem target %s not declared" % s)
type = targets[s]
if type == 'DISABLED' or type == 'EMPTY':
continue
t = bld.name_to_obj(s, bld.env)
bld.ASSERT(t is not None, "Subsystem target %s not found" % s)
for d in subsystems[s]:
type = targets[d['TARGET']]
if type != 'DISABLED' and type != 'EMPTY':
t.samba_deps_extended.append(d['TARGET'])
t2 = bld.name_to_obj(d['TARGET'], bld.env)
t2.samba_includes_extended.extend(t.samba_includes_extended)
t2.samba_deps_extended.extend(t.samba_deps_extended)
t.samba_deps_extended = unique_list(t.samba_deps_extended)
def build_dependencies(self):
'''This builds the dependency list for a target. It runs after all the targets are declared
The reason this is not just done in the SAMBA_*() rules is that we have no way of knowing
the full dependency list for a target until we have all of the targets declared.
'''
# we only should add extra library and object deps on libraries and binaries
if not self.samba_type in ['LIBRARY', 'BINARY', 'PYTHON']:
return
# we need to link against:
# 1) any direct system libs
# 2) any indirect system libs that come from subsystem dependencies
# 3) any direct local libs
# 4) any indirect local libs that come from subsystem dependencies
# 5) any direct objects
# 6) any indirect objects that come from subsystem dependencies
self.uselib = list(self.final_syslibs)
self.uselib_local = list(self.final_libs)
self.add_objects = list(self.final_objects)
debug('deps: computed dependencies for target %s: uselib=%s uselib_local=%s add_objects=%s',
self.sname, self.uselib, self.uselib_local, self.add_objects)
def build_includes(self):
'''This builds the right set of includes for a target.
One tricky part of this is that the includes= attribute for a
target needs to use paths which are relative to that targets
declaration directory (which we can get at via t.path).
The way this works is the includes list gets added as
samba_includes in the main build task declaration. Then this
function runs after all of the tasks are declared, and it
processes the samba_includes attribute to produce a includes=
attribute
'''
if getattr(self, 'samba_includes', None) is None:
return
bld = self.bld
inc_deps = includes_objects(bld, self, set(), {})
includes = []
# maybe add local includes
if getattr(self, 'local_include', True) == True and getattr(self, 'local_include_first', True):
includes.append('.')
includes.extend(self.samba_includes_extended)
if 'EXTRA_INCLUDES' in bld.env:
includes.extend(bld.env['EXTRA_INCLUDES'])
includes.append('#')
inc_set = set()
inc_abs = []
for d in inc_deps:
t = bld.name_to_obj(d, bld.env)
bld.ASSERT(t is not None, "Unable to find dependency %s for %s" % (d, self.sname))
inclist = getattr(t, 'samba_includes_extended', [])
if getattr(t, 'local_include', True) == True:
inclist.append('.')
if inclist == []:
continue
tpath = t.samba_abspath
for inc in inclist:
npath = tpath + '/' + inc
if not npath in inc_set:
inc_abs.append(npath)
inc_set.add(npath)
mypath = self.path.abspath(bld.env)
for inc in inc_abs:
relpath = os_path_relpath(inc, mypath)
includes.append(relpath)
if getattr(self, 'local_include', True) == True and not getattr(self, 'local_include_first', True):
includes.append('.')
# now transform the includes list to be relative to the top directory
# which is represented by '#' in waf. This allows waf to cache the
# includes lists more efficiently
includes_top = []
for i in includes:
if i[0] == '#':
# some are already top based
includes_top.append(i)
continue
absinc = os.path.join(self.path.abspath(), i)
relinc = os_path_relpath(absinc, self.bld.srcnode.abspath())
includes_top.append('#' + relinc)
self.includes = unique_list(includes_top)
debug('deps: includes for target %s: includes=%s',
self.sname, self.includes)
def add_init_functions(self):
'''This builds the right set of init functions'''
bld = self.bld
subsystems = LOCAL_CACHE(bld, 'INIT_FUNCTIONS')
# cope with the separated object lists from BINARY and LIBRARY targets
sname = self.sname
if sname.endswith('.objlist'):
sname = sname[0:-8]
modules = []
if sname in subsystems:
modules.append(sname)
m = getattr(self, 'samba_modules', None)
if m is not None:
modules.extend(TO_LIST(m))
m = getattr(self, 'samba_subsystem', None)
if m is not None:
modules.append(m)
if modules == []:
return
sentinal = getattr(self, 'init_function_sentinal', 'NULL')
targets = LOCAL_CACHE(bld, 'TARGET_TYPE')
cflags = getattr(self, 'samba_cflags', [])[:]
for m in modules:
bld.ASSERT(m in subsystems,
"No init_function defined for module '%s' in target '%s'" % (m, self.sname))
init_fn_list = []
for d in subsystems[m]:
if targets[d['TARGET']] != 'DISABLED':
init_fn_list.append(d['INIT_FUNCTION'])
if init_fn_list == []:
cflags.append('-DSTATIC_%s_MODULES=%s' % (m, sentinal))
else:
cflags.append('-DSTATIC_%s_MODULES=%s' % (m, ','.join(init_fn_list) + ',' + sentinal))
self.ccflags = cflags
def check_duplicate_sources(bld, tgt_list):
'''see if we are compiling the same source file into multiple
subsystem targets for the same library or binary'''
debug('deps: checking for duplicate sources')
targets = LOCAL_CACHE(bld, 'TARGET_TYPE')
ret = True
seen = set()
'''
# this was useful for finding problems with the autogenerated rules
for t in tgt_list:
base_list = set()
sources = TO_LIST(getattr(t, 'source', ''))
for s in sources:
bname = os.path.basename(s)
if bname in base_list:
print "Suspicious duplicate name %s in %s" % (bname, t.sname)
continue
base_list.add(bname)
'''
for t in tgt_list:
obj_sources = getattr(t, 'source', '')
tpath = os_path_relpath(t.path.abspath(bld.env), t.env['BUILD_DIRECTORY'] + '/default')
obj_sources = bld.SUBDIR(tpath, obj_sources)
t.samba_source_set = set(TO_LIST(obj_sources))
for t in tgt_list:
if not targets[t.sname] in [ 'LIBRARY', 'BINARY', 'PYTHON' ]:
continue
sources = []
for obj in t.add_objects:
t2 = t.bld.name_to_obj(obj, bld.env)
source_set = getattr(t2, 'samba_source_set', set())
sources.append( { 'dep':obj, 'src':source_set} )
for s in sources:
for s2 in sources:
if s['dep'] == s2['dep']: continue
common = s['src'].intersection(s2['src'])
if common.difference(seen):
print("Target %s has duplicate source files in %s and %s : %s" % (t.sname,
s['dep'], s2['dep'],
common))
seen = seen.union(common)
ret = False
return ret
def check_orpaned_targets(bld, tgt_list):
'''check if any build targets are orphaned'''
target_dict = LOCAL_CACHE(bld, 'TARGET_TYPE')
debug('deps: checking for orphaned targets')
for t in tgt_list:
if getattr(t, 'samba_used', False) == True:
continue
type = target_dict[t.sname]
if not type in ['BINARY', 'LIBRARY', 'MODULE', 'ET', 'PYTHON']:
if re.search('^PIDL_', t.sname) is None:
print "Target %s of type %s is unused by any other target" % (t.sname, type)
def show_final_deps(bld, tgt_list):
'''show the final dependencies for all targets'''
targets = LOCAL_CACHE(bld, 'TARGET_TYPE')
for t in tgt_list:
if not targets[t.sname] in ['LIBRARY', 'BINARY', 'PYTHON']:
continue
debug('deps: final dependencies for target %s: uselib=%s uselib_local=%s add_objects=%s',
t.sname, t.uselib, t.uselib_local, t.add_objects)
def add_samba_attributes(bld, tgt_list):
'''ensure a target has a the required samba attributes'''
targets = LOCAL_CACHE(bld, 'TARGET_TYPE')
for t in tgt_list:
if t.name != '':
t.sname = t.name
else:
t.sname = t.target
t.samba_type = targets[t.sname]
t.samba_abspath = t.path.abspath(bld.env)
t.samba_deps_extended = t.samba_deps[:]
t.samba_includes_extended = TO_LIST(t.samba_includes)[:]
t.ccflags = getattr(t, 'samba_cflags', '')
def build_direct_deps(bld, tgt_list):
'''build the direct_objects and direct_libs sets for each target'''
targets = LOCAL_CACHE(bld, 'TARGET_TYPE')
global_deps = bld.env.GLOBAL_DEPENDENCIES
for t in tgt_list:
t.direct_objects = set()
t.direct_libs = set()
t.direct_syslibs = set()
deps = t.samba_deps_extended
deps.extend(global_deps)
for d in deps:
d = EXPAND_ALIAS(bld, d)
if d == t.sname: continue
if not d in targets:
print "Unknown dependency %s in %s" % (d, t.sname)
raise
if targets[d] in [ 'EMPTY', 'DISABLED' ]:
continue
if targets[d] == 'SYSLIB':
t.direct_syslibs.add(d)
continue
t2 = bld.name_to_obj(d, bld.env)
if t2 is None:
print "no task %s type %s" % (d, targets[d])
if t2.samba_type in [ 'LIBRARY', 'MODULE' ]:
t.direct_libs.add(d)
elif t2.samba_type in [ 'SUBSYSTEM', 'ASN1', 'PYTHON' ]:
t.direct_objects.add(d)
debug('deps: built direct dependencies')
def dependency_loop(loops, t, target):
'''add a dependency loop to the loops dictionary'''
if t.sname == target:
return
if not target in loops:
loops[target] = set()
if not t.sname in loops[target]:
loops[target].add(t.sname)
def indirect_libs(bld, t, chain, loops):
'''recursively calculate the indirect library dependencies for a target
An indirect library is a library that results from a dependency on
a subsystem
'''
ret = getattr(t, 'indirect_libs', None)
if ret is not None:
return ret
ret = set()
for obj in t.direct_objects:
if obj in chain:
dependency_loop(loops, t, obj)
continue
chain.add(obj)
t2 = bld.name_to_obj(obj, bld.env)
r2 = indirect_libs(bld, t2, chain, loops)
chain.remove(obj)
ret = ret.union(t2.direct_libs)
ret = ret.union(r2)
for obj in indirect_objects(bld, t, set(), loops):
if obj in chain:
dependency_loop(loops, t, obj)
continue
chain.add(obj)
t2 = bld.name_to_obj(obj, bld.env)
r2 = indirect_libs(bld, t2, chain, loops)
chain.remove(obj)
ret = ret.union(t2.direct_libs)
ret = ret.union(r2)
t.indirect_libs = ret
return ret
def indirect_syslibs(bld, t, chain, loops):
'''recursively calculate the indirect system library dependencies for a target
An indirect syslib results from a subsystem dependency
'''
ret = getattr(t, 'indirect_syslibs', None)
if ret is not None:
return ret
ret = set()
for obj in t.direct_objects:
if obj in chain:
dependency_loop(loops, t, obj)
continue
chain.add(obj)
t2 = bld.name_to_obj(obj, bld.env)
r2 = indirect_syslibs(bld, t2, chain, loops)
chain.remove(obj)
ret = ret.union(t2.direct_syslibs)
ret = ret.union(r2)
t.indirect_syslibs = ret
return ret
def indirect_objects(bld, t, chain, loops):
'''recursively calculate the indirect object dependencies for a target
indirect objects are the set of objects from expanding the
subsystem dependencies
'''
ret = getattr(t, 'indirect_objects', None)
if ret is not None: return ret
ret = set()
for lib in t.direct_objects:
if lib in chain:
dependency_loop(loops, t, lib)
continue
chain.add(lib)
t2 = bld.name_to_obj(lib, bld.env)
r2 = indirect_objects(bld, t2, chain, loops)
chain.remove(lib)
ret = ret.union(t2.direct_objects)
ret = ret.union(r2)
t.indirect_objects = ret
return ret
def extended_objects(bld, t, chain):
'''recursively calculate the extended object dependencies for a target
extended objects are the union of:
- direct objects
- indirect objects
- direct and indirect objects of all direct and indirect libraries
'''
ret = getattr(t, 'extended_objects', None)
if ret is not None: return ret
ret = set()
ret = ret.union(t.direct_objects)
ret = ret.union(t.indirect_objects)
for lib in t.direct_libs:
if lib in chain:
continue
t2 = bld.name_to_obj(lib, bld.env)
chain.add(lib)
r2 = extended_objects(bld, t2, chain)
chain.remove(lib)
ret = ret.union(t2.direct_objects)
ret = ret.union(t2.indirect_objects)
ret = ret.union(r2)
t.extended_objects = ret
return ret
def includes_objects(bld, t, chain, inc_loops):
'''recursively calculate the includes object dependencies for a target
includes dependencies come from either library or object dependencies
'''
ret = getattr(t, 'includes_objects', None)
if ret is not None:
return ret
ret = t.direct_objects.copy()
ret = ret.union(t.direct_libs)
for obj in t.direct_objects:
if obj in chain:
dependency_loop(inc_loops, t, obj)
continue
chain.add(obj)
t2 = bld.name_to_obj(obj, bld.env)
r2 = includes_objects(bld, t2, chain, inc_loops)
chain.remove(obj)
ret = ret.union(t2.direct_objects)
ret = ret.union(r2)
for lib in t.direct_libs:
if lib in chain:
dependency_loop(inc_loops, t, lib)
continue
chain.add(lib)
t2 = bld.name_to_obj(lib, bld.env)
r2 = includes_objects(bld, t2, chain, inc_loops)
chain.remove(lib)
ret = ret.union(t2.direct_objects)
ret = ret.union(r2)
t.includes_objects = ret
return ret
def break_dependency_loops(bld, tgt_list):
'''find and break dependency loops'''
loops = {}
inc_loops = {}
# build up the list of loops
for t in tgt_list:
indirect_objects(bld, t, set(), loops)
indirect_libs(bld, t, set(), loops)
indirect_syslibs(bld, t, set(), loops)
includes_objects(bld, t, set(), inc_loops)
# break the loops
for t in tgt_list:
if t.sname in loops:
for attr in ['direct_objects', 'indirect_objects', 'direct_libs', 'indirect_libs']:
objs = getattr(t, attr, set())
setattr(t, attr, objs.difference(loops[t.sname]))
for loop in loops:
debug('deps: Found dependency loops for target %s : %s', loop, loops[loop])
# expand the loops mapping by one level
for loop in loops.copy():
for tgt in loops[loop]:
if tgt in loops:
loops[loop] = loops[loop].union(loops[tgt])
# expand indirect subsystem and library loops
for loop in loops.copy():
t = bld.name_to_obj(loop, bld.env)
if t.samba_type in ['SUBSYSTEM']:
loops[loop] = loops[loop].union(t.indirect_objects, t.direct_objects)
if t.samba_type in ['LIBRARY']:
loops[loop] = loops[loop].union(t.indirect_libs, t.direct_libs)
if loop in loops[loop]:
loops[loop].remove(loop)
# add in the replacement dependencies
for t in tgt_list:
for loop in loops:
for attr in ['direct_objects', 'indirect_objects', 'direct_libs', 'indirect_libs']:
objs = getattr(t, attr, set())
if loop in objs:
diff = loops[loop].difference(objs)
if t.sname in diff:
diff.remove(t.sname)
if diff:
debug('deps: Expanded target %s of type %s from loop %s by %s', t.sname, t.samba_type, loop, diff)
objs = objs.union(diff)
if t.sname == 'ldb_password_hash':
debug('deps: setting %s %s to %s', t.sname, attr, objs)
setattr(t, attr, objs)
def calculate_final_deps(bld, tgt_list, loops):
'''calculate the final library and object dependencies'''
for t in tgt_list:
# start with the maximum possible list
t.final_syslibs = t.direct_syslibs.union(indirect_syslibs(bld, t, set(), loops))
t.final_libs = t.direct_libs.union(indirect_libs(bld, t, set(), loops))
t.final_objects = t.direct_objects.union(indirect_objects(bld, t, set(), loops))
for t in tgt_list:
# don't depend on ourselves
if t.sname in t.final_libs:
t.final_libs.remove(t.sname)
if t.sname in t.final_objects:
t.final_objects.remove(t.sname)
# find any library loops
for t in tgt_list:
if t.samba_type in ['LIBRARY', 'PYTHON']:
for l in t.final_libs.copy():
t2 = bld.name_to_obj(l, bld.env)
if t.sname in t2.final_libs:
# we could break this in either direction. If one of the libraries
# has a version number, and will this be distributed publicly, then
# we should make it the lower level library in the DAG
debug('deps: removing library loop %s from %s', t.sname, t2.sname)
dependency_loop(loops, t, t2.sname)
t2.final_libs.remove(t.sname)
for type in ['BINARY']:
for t in tgt_list:
if t.samba_type != type: continue
# if we will indirectly link to a target then we don't need it
new = t.final_objects.copy()
for l in t.final_libs:
t2 = bld.name_to_obj(l, bld.env)
t2_obj = extended_objects(bld, t2, set())
dup = new.intersection(t2_obj)
if dup:
debug('deps: removing dups from %s of type %s: %s also in %s %s',
t.sname, t.samba_type, dup, t2.samba_type, l)
new = new.difference(dup)
changed = True
t.final_objects = new
for loop in loops:
debug('deps: Found dependency loops for target %s : %s', loop, loops[loop])
# we now need to make corrections for any library loops we broke up
# any target that depended on the target of the loop and doesn't
# depend on the source of the loop needs to get the loop source added
for type in ['BINARY','PYTHON','LIBRARY']:
for t in tgt_list:
if t.samba_type != type: continue
for loop in loops:
if loop in t.final_libs:
diff = loops[loop].difference(t.final_libs)
if t.sname in diff:
diff.remove(t.sname)
if diff:
debug('deps: Expanded target %s by loop %s libraries %s', t.sname, loop, diff)
t.final_libs = t.final_libs.union(diff)
debug('deps: removed duplicate dependencies')
######################################################################
# this provides a way to save our dependency calculations between runs
savedeps_version = 3
savedeps_inputs = ['samba_deps', 'samba_includes', 'local_include', 'local_include_first', 'samba_cflags', 'source']
savedeps_outputs = ['uselib', 'uselib_local', 'add_objects', 'includes', 'ccflags']
savedeps_outenv = ['INC_PATHS']
savedeps_caches = ['GLOBAL_DEPENDENCIES', 'TARGET_ALIAS', 'TARGET_TYPE', 'INIT_FUNCTIONS']
savedeps_files = ['buildtools/wafsamba/samba_deps.py']
def save_samba_deps(bld, tgt_list):
'''save the dependency calculations between builds, to make
further builds faster'''
denv = Environment.Environment()
denv.version = savedeps_version
denv.savedeps_inputs = savedeps_inputs
denv.savedeps_outputs = savedeps_outputs
denv.input = {}
denv.output = {}
denv.outenv = {}
denv.caches = {}
denv.files = {}
for f in savedeps_files:
denv.files[f] = os.stat(os.path.join(bld.srcnode.abspath(), f)).st_mtime
for c in savedeps_caches:
denv.caches[c] = LOCAL_CACHE(bld, c)
for t in tgt_list:
# save all the input attributes for each target
tdeps = {}
for attr in savedeps_inputs:
v = getattr(t, attr, None)
if v is not None:
tdeps[attr] = v
if tdeps != {}:
denv.input[t.sname] = tdeps
# save all the output attributes for each target
tdeps = {}
for attr in savedeps_outputs:
v = getattr(t, attr, None)
if v is not None:
tdeps[attr] = v
if tdeps != {}:
denv.output[t.sname] = tdeps
tdeps = {}
for attr in savedeps_outenv:
if attr in t.env:
tdeps[attr] = t.env[attr]
if tdeps != {}:
denv.outenv[t.sname] = tdeps
depsfile = os.path.join(bld.bdir, "sambadeps")
denv.store(depsfile)
def load_samba_deps(bld, tgt_list):
'''load a previous set of build dependencies if possible'''
depsfile = os.path.join(bld.bdir, "sambadeps")
denv = Environment.Environment()
try:
debug('deps: checking saved dependencies')
denv.load(depsfile)
if (denv.version != savedeps_version or
denv.savedeps_inputs != savedeps_inputs or
denv.savedeps_outputs != savedeps_outputs):
return False
except:
return False
# check if critical files have changed
for f in savedeps_files:
if f not in denv.files:
return False
if denv.files[f] != os.stat(os.path.join(bld.srcnode.abspath(), f)).st_mtime:
return False
# check if caches are the same
for c in savedeps_caches:
if c not in denv.caches or denv.caches[c] != LOCAL_CACHE(bld, c):
return False
# check inputs are the same
for t in tgt_list:
tdeps = {}
for attr in savedeps_inputs:
v = getattr(t, attr, None)
if v is not None:
tdeps[attr] = v
if t.sname in denv.input:
olddeps = denv.input[t.sname]
else:
olddeps = {}
if tdeps != olddeps:
#print '%s: \ntdeps=%s \nodeps=%s' % (t.sname, tdeps, olddeps)
return False
# put outputs in place
for t in tgt_list:
if not t.sname in denv.output: continue
tdeps = denv.output[t.sname]
for a in tdeps:
setattr(t, a, tdeps[a])
# put output env vars in place
for t in tgt_list:
if not t.sname in denv.outenv: continue
tdeps = denv.outenv[t.sname]
for a in tdeps:
t.env[a] = tdeps[a]
debug('deps: loaded saved dependencies')
return True
def check_project_rules(bld):
'''check the project rules - ensuring the targets are sane'''
targets = LOCAL_CACHE(bld, 'TARGET_TYPE')
loops = {}
inc_loops = {}
# build a list of task generators we are interested in
tgt_list = []
for tgt in targets:
type = targets[tgt]
if not type in ['SUBSYSTEM', 'MODULE', 'BINARY', 'LIBRARY', 'ASN1', 'PYTHON']:
continue
t = bld.name_to_obj(tgt, bld.env)
if t is None:
print "Target %s of type %s has no task generator" % (tgt, type)
raise
tgt_list.append(t)
add_samba_attributes(bld, tgt_list)
if load_samba_deps(bld, tgt_list):
return
print "Checking project rules ..."
debug('deps: project rules checking started')
expand_subsystem_deps(bld)
build_direct_deps(bld, tgt_list)
break_dependency_loops(bld, tgt_list)
calculate_final_deps(bld, tgt_list, loops)
# run the various attribute generators
for f in [ build_dependencies, build_includes, add_init_functions ]:
debug('deps: project rules checking %s', f)
for t in tgt_list: f(t)
debug('deps: project rules stage1 completed')
#check_orpaned_targets(bld, tgt_list)
if not check_duplicate_sources(bld, tgt_list):
print "Duplicate sources present - aborting"
sys.exit(1)
show_final_deps(bld, tgt_list)
debug('deps: project rules checking completed - %u targets checked',
len(tgt_list))
save_samba_deps(bld, tgt_list)
print "Project rules pass"
def CHECK_PROJECT_RULES(bld):
'''enable checking of project targets for sanity'''
if bld.env.added_project_rules:
return
bld.env.added_project_rules = True
bld.add_pre_fun(check_project_rules)
Build.BuildContext.CHECK_PROJECT_RULES = CHECK_PROJECT_RULES