gnome: Work around GNU ld bug with -rpath,$ORIGIN

g-ir-scanner doesn't understand -rpath, so we use -L instead which
has the same effect.

Closes https://github.com/mesonbuild/meson/issues/1911

mesonbuild/backend/backends.py

@@ -294,6 +294,15 @@ class Backend:
             raise MesonException(m.format(target.name))
         return l
 
+    def determine_rpath_dirs(self, target):
+        link_deps = target.get_all_link_deps()
+        result = []
+        for ld in link_deps:
+            prospective = self.get_target_dir(ld)
+            if prospective not in result:
+                result.append(prospective)
+        return result
+
     def object_filename_from_source(self, target, source, is_unity):
         if isinstance(source, mesonlib.File):
             source = source.fname

mesonbuild/backend/ninjabackend.py

@@ -2334,15 +2334,6 @@ rule FORTRAN_DEP_HACK
         elem.add_item('LINK_ARGS', commands)
         return elem
 
-    def determine_rpath_dirs(self, target):
-        link_deps = target.get_all_link_deps()
-        result = []
-        for ld in link_deps:
-            prospective = self.get_target_dir(ld)
-            if prospective not in result:
-                result.append(prospective)
-        return result
-
     def get_dependency_filename(self, t):
         if isinstance(t, build.SharedLibrary):
             return os.path.join(self.get_target_private_dir(t), self.get_target_filename(t) + '.symbols')

mesonbuild/interpreter.py

@@ -1010,10 +1010,9 @@ class CompilerHolder(InterpreterObject):
         return []
 
 ModuleState = namedtuple('ModuleState', [
-    'build_to_src', 'subdir', 'environment', 'project_name',
-    'project_version', 'compilers', 'targets', 'data', 'headers',
-    'man', 'global_args', 'project_args', 'build_machine',
-    'host_machine', 'target_machine'])
+    'build_to_src', 'subdir', 'environment', 'project_name', 'project_version',
+    'backend', 'compilers', 'targets', 'data', 'headers', 'man', 'global_args',
+    'project_args', 'build_machine', 'host_machine', 'target_machine'])
 
 class ModuleHolder(InterpreterObject):
     def __init__(self, modname, module, interpreter):
@@ -1039,6 +1038,9 @@ class ModuleHolder(InterpreterObject):
             environment=self.interpreter.environment,
             project_name=self.interpreter.build.project_name,
             project_version=self.interpreter.build.dep_manifest[self.interpreter.active_projectname],
+            # The backend object is under-used right now, but we will need it:
+            # https://github.com/mesonbuild/meson/issues/1419
+            backend=self.interpreter.backend,
             compilers=self.interpreter.build.compilers,
             targets=self.interpreter.build.targets,
             data=self.interpreter.build.data,

mesonbuild/modules/gnome.py

@@ -288,15 +288,23 @@ class GnomeModule(ExtensionModule):
 
     def _get_link_args(self, state, lib, depends=None, include_rpath=False,
                        use_gir_args=False):
+        # Construct link args
         if gir_has_extra_lib_arg() and use_gir_args:
-            link_command = ['--extra-library=%s' % lib.name]
+            link_command = ['--extra-library=' + lib.name]
         else:
-            link_command = ['-l%s' % lib.name]
+            link_command = ['-l' + lib.name]
         if isinstance(lib, build.SharedLibrary):
-            libdir = os.path.join(state.environment.get_build_dir(), lib.subdir)
-            link_command += ['-L%s' % libdir]
+            libdir = state.backend.get_target_dir(lib)
+            link_command.append('-L' + libdir)
+            # Needed for the following binutils bug:
+            # https://github.com/mesonbuild/meson/issues/1911
+            # However, g-ir-scanner does not understand -Wl,-rpath
+            # so we need to use -L instead
+            for d in state.backend.determine_rpath_dirs(lib):
+                d = os.path.join(state.environment.get_build_dir(), d)
+                link_command.append('-L' + d)
             if include_rpath:
-                link_command += ['-Wl,-rpath %s' % libdir]
+                link_command.append('-Wl,-rpath,' + libdir)
             if depends:
                 depends.append(lib)
         return link_command
@@ -536,6 +544,13 @@ class GnomeModule(ExtensionModule):
             scan_command += ['--program', girtarget]
         elif isinstance(girtarget, build.SharedLibrary):
             libname = girtarget.get_basename()
+            # Needed for the following binutils bug:
+            # https://github.com/mesonbuild/meson/issues/1911
+            # However, g-ir-scanner does not understand -Wl,-rpath
+            # so we need to use -L instead
+            for d in state.backend.determine_rpath_dirs(girtarget):
+                d = os.path.join(state.environment.get_build_dir(), d)
+                scan_command.append('-L' + d)
             scan_command += ['--library', libname]
         scankwargs = {'output': girfile,
                       'input': libsources,