s4-waf: added implied_deps for system libraries

when we use a system version of a library such as talloc, then we
no longer get the automtica dependency propogation of talloc implying
libreplace. That means we don't get the includes for libreplace, which
means things can fail to build.

To fix this this change adds an implied_deps option to
CHECK_BUNDLED_SYSTEM(), which tells the samba_deps module to add an
implied dependency on the listed targets if the system library is
chosen.

2 files changed, 19 insertions, 2 deletions

diff --git a/buildtools/wafsamba/samba_bundled.py b/buildtools/wafsamba/samba_bundled.py
index b2d1b0ef14..28116fcd69 100644
--- a/buildtools/wafsamba/samba_bundled.py
+++ b/buildtools/wafsamba/samba_bundled.py
@@ -46,7 +46,8 @@ Options.Handler.BUNDLED_EXTENSION_DEFAULT = BUNDLED_EXTENSION_DEFAULT
 @runonce
 @conf
 def CHECK_BUNDLED_SYSTEM(conf, libname, minversion='0.0.0',
-                         checkfunctions=None, headers=None, onlyif=None):
+                         checkfunctions=None, headers=None,
+                         onlyif=None, implied_deps=None):
     '''check if a library is available as a system library.
     this first tries via pkg-config, then if that fails
     tries by testing for a specified function in the specified lib
@@ -76,10 +77,14 @@ def CHECK_BUNDLED_SYSTEM(conf, libname, minversion='0.0.0',
                       msg='Checking for system %s >= %s' % (libname, minversion)):
         conf.SET_TARGET_TYPE(libname, 'SYSLIB')
         conf.env[found] = True
+        if implied_deps:
+            conf.SET_SYSLIB_DEPS(libname, implied_deps)
         return True
     if checkfunctions is not None:
         if conf.CHECK_FUNCS_IN(checkfunctions, libname, headers=headers, empty_decl=False):
             conf.env[found] = True
+            if implied_deps:
+                conf.SET_SYSLIB_DEPS(libname, implied_deps)
             return True
     conf.env[found] = False
     if 'NONE' in conf.env.BUNDLED_LIBS or '!'+libname in conf.env.BUNDLED_LIBS:
diff --git a/buildtools/wafsamba/samba_deps.py b/buildtools/wafsamba/samba_deps.py
index 02d4c421d5..bc9325f214 100644
--- a/buildtools/wafsamba/samba_deps.py
+++ b/buildtools/wafsamba/samba_deps.py
@@ -22,6 +22,13 @@ def TARGET_ALIAS(bld, target, alias):
 Build.BuildContext.TARGET_ALIAS = TARGET_ALIAS
 
 
+@conf
+def SET_SYSLIB_DEPS(conf, target, deps):
+    '''setup some implied dependencies for a SYSLIB'''
+    cache = LOCAL_CACHE(conf, 'SYSLIB_DEPS')
+    cache[target] = deps
+
+
 def EXPAND_ALIAS(bld, target):
     '''expand a target name via an alias'''
     aliases = LOCAL_CACHE(bld, 'TARGET_ALIAS')
@@ -308,6 +315,7 @@ def build_direct_deps(bld, tgt_list):
     '''build the direct_objects and direct_libs sets for each target'''
 
     targets  = LOCAL_CACHE(bld, 'TARGET_TYPE')
+    syslib_deps  = LOCAL_CACHE(bld, 'SYSLIB_DEPS')
     global_deps = bld.env.GLOBAL_DEPENDENCIES
 
     for t in tgt_list:
@@ -326,6 +334,10 @@ def build_direct_deps(bld, tgt_list):
                 continue
             if targets[d] == 'SYSLIB':
                 t.direct_syslibs.add(d)
+                if d in syslib_deps:
+                    for implied in TO_LIST(syslib_deps[d]):
+                        print("Adding implied lib %s to %s" % (implied, t.sname))
+                        t.direct_libs.add(implied)
                 continue
             t2 = bld.name_to_obj(d, bld.env)
             if t2 is None:
@@ -622,7 +634,7 @@ 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_caches  = ['GLOBAL_DEPENDENCIES', 'TARGET_ALIAS', 'TARGET_TYPE', 'INIT_FUNCTIONS', 'SYSLIB_DEPS']
 savedeps_files   = ['buildtools/wafsamba/samba_deps.py']
 
 def save_samba_deps(bld, tgt_list):