Add flags to cc_shared_library for easier debugging
--//examples:incompatible_link_once=False[default = False]
When True, it will be an error to link the same library more than once
unless it has the tag LINKABLE_MORE_THAN_ONCE
--//examples:experimental_debug=True[default = False]
When True, it will generate files listing the exports of each cc_shared_library
and which libraries are linked to it statically.
RELNOTES:none
PiperOrigin-RevId: 311323625
Change-Id: I340cc71965650f7c9dd7ef7fb9656da362021527
diff --git a/.bazelci/presubmit.yml b/.bazelci/presubmit.yml
index fdee8b7..f227fc0 100644
--- a/.bazelci/presubmit.yml
+++ b/.bazelci/presubmit.yml
@@ -53,8 +53,10 @@
- "//examples/test_cc_shared_library/..."
build_flags:
- "--experimental_cc_shared_library"
+ - "--//examples:incompatible_link_once=True"
test_flags:
- "--test_timeout=120"
- "--experimental_cc_shared_library"
+ - "--//examples:incompatible_link_once=True"
test_targets:
- "//examples/test_cc_shared_library/..."
diff --git a/examples/BUILD b/examples/BUILD
index d9178c1..0bfcd24 100644
--- a/examples/BUILD
+++ b/examples/BUILD
@@ -12,5 +12,19 @@
# See the License for the specific language governing permissions and
# limitations under the License.
+load("@bazel_skylib//rules:common_settings.bzl", "bool_flag")
+
# A collection of examples showing the usage of rules_cc
licenses(["notice"])
+
+bool_flag(
+ name = "incompatible_link_once",
+ build_setting_default = False,
+ visibility = ["//visibility:public"],
+)
+
+bool_flag(
+ name = "experimental_debug",
+ build_setting_default = False,
+ visibility = ["//visibility:public"],
+)
diff --git a/examples/experimental_cc_shared_library.bzl b/examples/experimental_cc_shared_library.bzl
index ed3124c..f4a738f 100644
--- a/examples/experimental_cc_shared_library.bzl
+++ b/examples/experimental_cc_shared_library.bzl
@@ -5,6 +5,7 @@
--experimental_cc_shared_library
"""
+load("@bazel_skylib//rules:common_settings.bzl", "BuildSettingInfo")
load("//cc:find_cc_toolchain.bzl", "find_cc_toolchain")
# TODO(#5200): Add export_define to library_to_link and cc_library
@@ -363,9 +364,23 @@
for export in ctx.attr.roots:
exports[str(export.label)] = True
+ debug_files = []
+ if ctx.attr._experimental_debug[BuildSettingInfo].value:
+ exports_debug_file = ctx.actions.declare_file(ctx.label.name + "_exports.txt")
+ ctx.actions.write(content = "\n".join(exports.keys()), output = exports_debug_file)
+
+ link_once_static_libs_debug_file = ctx.actions.declare_file(ctx.label.name + "_link_once_static_libs.txt")
+ ctx.actions.write(content = "\n".join(link_once_static_libs), output = link_once_static_libs_debug_file)
+
+ debug_files.append(exports_debug_file)
+ debug_files.append(link_once_static_libs_debug_file)
+
+ if not ctx.attr._incompatible_link_once[BuildSettingInfo].value:
+ link_once_static_libs = []
+
return [
DefaultInfo(
- files = depset([linking_outputs.library_to_link.resolved_symlink_dynamic_library]),
+ files = depset([linking_outputs.library_to_link.resolved_symlink_dynamic_library] + debug_files),
runfiles = runfiles,
),
CcSharedLibraryInfo(
@@ -439,6 +454,8 @@
"static_deps": attr.string_list(),
"user_link_flags": attr.string_list(),
"_cc_toolchain": attr.label(default = "@bazel_tools//tools/cpp:current_cc_toolchain"),
+ "_experimental_debug": attr.label(default = "//examples:experimental_debug"),
+ "_incompatible_link_once": attr.label(default = "//examples:incompatible_link_once"),
},
toolchains = ["@rules_cc//cc:toolchain_type"], # copybara-use-repo-external-label
fragments = ["cpp"],
