Support cc_lib targets that only provide a dynamic library and prevent re-anchoring when siblings are generated

extensions/bindgen/private/bindgen.bzl

@@ -179,9 +179,13 @@ def _generate_cc_link_build_info(ctx, cc_lib):
                 rustc_flags.append("-lstatic={}".format(get_lib_name_default(lib.pic_static_library)))
                 linker_search_paths.append(lib.pic_static_library.dirname)
                 compile_data.append(lib.pic_static_library)
+            elif lib.dynamic_library:
+                rustc_flags.append("-ldylib={}".format(get_lib_name_default(lib.dynamic_library)))
+                linker_search_paths.append(lib.dynamic_library.dirname)
+                compile_data.append(lib.dynamic_library)
 
     if not compile_data:
-        fail("No static libraries found in {}".format(
+        fail("No static or dynamic libraries found in {}".format(
             cc_lib.label,
         ))
 

extensions/bindgen/test/analysis/bindgen_test.bzl

@@ -1,6 +1,7 @@
 """Analysis test for for rust_bindgen_library rule."""
 
-load("@rules_cc//cc:defs.bzl", "cc_library")
+load("@rules_cc//cc:cc_shared_library.bzl", "cc_shared_library")
+load("@rules_cc//cc:defs.bzl", "cc_import", "cc_library")
 load("@rules_rust//rust:defs.bzl", "rust_binary")
 load("@rules_rust_bindgen//:defs.bzl", "rust_bindgen_library")
 load("@rules_testing//lib:analysis_test.bzl", "analysis_test", "test_suite")
@@ -100,12 +101,52 @@ def _test_cc_lib_object_merging_disabled(name):
         impl = _test_cc_lib_object_merging_disabled_impl,
     )
 
+def _test_cc_lib_dynamic_only_impl(env, target):
+    env.expect.that_int(len(target.actions)).is_greater_than(2)
+    env.expect.that_action(target.actions[0]).mnemonic().contains("RustBindgen")
+    env.expect.that_action(target.actions[1]).mnemonic().contains("FileWrite")
+    env.expect.that_action(target.actions[1]).content().contains("-ldylib=test_cc_lib_dynamic_only_cc_shared")
+
+def _test_cc_lib_dynamic_only(name):
+    cc_library(
+        name = name + "_cc_objects",
+        srcs = ["simple.cc"],
+        hdrs = ["simple.h"],
+        tags = ["manual"],
+    )
+    cc_shared_library(
+        name = name + "_cc_shared",
+        deps = [name + "_cc_objects"],
+        tags = ["manual"],
+    )
+    cc_import(
+        name = name + "_cc",
+        shared_library = name + "_cc_shared",
+        hdrs = ["simple.h"],
+        tags = ["manual"],
+    )
+
+    rust_bindgen_library(
+        name = name + "_rust_bindgen",
+        cc_lib = name + "_cc",
+        header = "simple.h",
+        tags = ["manual"],
+        edition = "2021",
+    )
+
+    analysis_test(
+        name = name,
+        target = name + "_rust_bindgen__bindgen",
+        impl = _test_cc_lib_dynamic_only_impl,
+    )
+
 def bindgen_test_suite(name):
     test_suite(
         name = name,
         tests = [
             _test_cc_linkopt,
             _test_cc_lib_object_merging,
             _test_cc_lib_object_merging_disabled,
+            _test_cc_lib_dynamic_only,
         ],
     )

rust/private/rust_analyzer.bzl

@@ -266,7 +266,7 @@ def _create_single_crate(ctx, attrs, info):
 
     # We're only interested in the build info for local crates as these are the
     # only ones for which we want build file watching and code lens runnables support.
-    if not is_external and not is_generated:
+    if not is_external:
         crate["build"] = {
             "build_file": _WORKSPACE_TEMPLATE + ctx.build_file_path,
             # Emit canonical `//pkg:name` form. Bazel's BEP reports action
@@ -280,8 +280,16 @@ def _create_single_crate(ctx, attrs, info):
     if is_generated:
         srcs = getattr(ctx.rule.files, "srcs", [])
         src_map = {src.short_path: src for src in srcs if src.is_source}
+
+        # Only re-anchor into the workspace when every sibling src lives there too.
+        has_generated_srcs = any([
+            not src.is_source
+            for src in srcs
+            if src.short_path != info.crate.root.short_path
+        ])
         if info.crate.root.short_path in src_map:
-            crate["root_module"] = _WORKSPACE_TEMPLATE + src_map[info.crate.root.short_path].path
+            if not has_generated_srcs:
+                crate["root_module"] = _WORKSPACE_TEMPLATE + src_map[info.crate.root.short_path].path
             crate["source"]["include_dirs"].extend([
                 _WORKSPACE_TEMPLATE + src_map[info.crate.root.short_path].dirname,
                 path_prefix + info.crate.root.dirname,