Bug 1861291 - Move relrhack manual interdependency to the backend. r=…

…firefox-build-system-reviewers,ahochheiden

Differential Revision: https://phabricator.services.mozilla.com/D191924

config/recurse.mk

@@ -192,12 +192,6 @@ endif
 
 # Interdependencies that moz.build world don't know about yet for compilation.
 # Note some others are hardcoded or "guessed" in recursivemake.py and emitter.py
-ifdef RELRHACK
-# When building with RELR-based ELF hack, we need to build the relevant parts
-# before any target.
-$(filter %/target,$(compile_targets)): build/unix/elfhack/host build/unix/elfhack/inject/target-objects
-endif
-
 ifdef MOZ_USING_WASM_SANDBOXING
 security/rlbox/pre-compile media/libsoundtouch/src/pre-compile: config/external/wasm2c_sandbox_compiler/host
 dom/media/ogg/target-objects extensions/spellcheck/hunspell/glue/target-objects gfx/thebes/target-objects parser/expat/target-objects parser/htmlparser/target-objects gfx/ots/src/target-objects: security/rlbox/pre-compile

python/mozbuild/mozbuild/backend/recursivemake.py

@@ -437,6 +437,7 @@ def consume_object(self, obj):
 
         if isinstance(obj, Linkable):
             self._process_test_support_file(obj)
+            self._process_relrhack(obj)
 
         if isinstance(obj, DirectoryTraversal):
             self._process_directory_traversal(obj, backend_file)
@@ -1237,6 +1238,16 @@ def _process_simple_program(self, obj, backend_file):
     def _process_host_simple_program(self, program, backend_file):
         backend_file.write("HOST_SIMPLE_PROGRAMS += %s\n" % program)
 
+    def _process_relrhack(self, obj):
+        if isinstance(
+            obj, (SimpleProgram, Program, SharedLibrary)
+        ) and obj.config.substs.get("RELRHACK"):
+            # When building with RELR-based ELF hack, we need to build the relevant parts
+            # before any target.
+            node = self._compile_graph[self._build_target_for_obj(obj)]
+            node.add("build/unix/elfhack/host")
+            node.add("build/unix/elfhack/inject/target-objects")
+
     def _process_test_support_file(self, obj):
         # Ensure test support programs and libraries are tracked by an
         # install manifest for the benefit of the test packager.