Add feature injection

Add feature injection to toolchain gcc extension. This option will
allow users to add external defined features.

Author: nradakovic

MODULE.bazel

@@ -27,7 +27,7 @@ bazel_dep(name = "score_bazel_platforms", version = "0.1.2")
 # *******************************************************************************
 # C++ Rules for Bazel
 # *******************************************************************************
-bazel_dep(name = "rules_cc", version = "0.2.14")
+bazel_dep(name = "rules_cc", version = "0.2.17")
 
 # *******************************************************************************
 # Needed by S-CORE CI Automatic checks

MODULE.bazel.lock

@@ -45,7 +45,8 @@ platforms.
 `examples/BUILD`
 
 Contains small C++ targets used to verify compilation, linking, pthread
-support, and sanitizer integration.
+support, and optional sanitizer integration when sanitizer features are
+registered explicitly.
 
 `examples/test.sh`
 
@@ -85,4 +86,12 @@ In practice this means checking among other things:
 - correct toolchain registration and platform matching,
 - basic linking behavior,
 - feature coverage such as pthread-enabled builds,
-- optional sanitizer feature wiring for the local Linux toolchain path.
+- optional sanitizer feature wiring for the local Linux toolchain path.
+
+## Sanitizer Note
+
+Sanitizer features are not included by default by the generated toolchains.
+If a workspace wants to use targets such as `asan_test`, it must first
+register the sanitizer `cc_feature` definitions explicitly, for example via
+`extra_known_features` or `extra_enabled_features` when declaring the
+toolchain and by providing the feature definitions from `score_cpp_policies`.

docs/examples_and_validation.md

@@ -72,6 +72,8 @@ Flag and runtime attributes:
 - `extra_c_compile_flags`
 - `extra_cxx_compile_flags`
 - `extra_link_flags`
+- `extra_known_features`
+- `extra_enabled_features`
 - `ld_library_paths`
 - `runtime_ecosystem`
 - `use_base_constraints_only`
@@ -112,5 +114,9 @@ configurations for this activation step.
 - The extension is intended for the root module.
 - When `use_default_package` is enabled, the version matrix can inject extra
   include and link flags required by non-standard sysroot layouts.
+- Sanitizer features are not registered automatically. Workspaces that want
+  sanitizer support must provide the relevant rule-based `cc_feature`
+  definitions explicitly, typically from `score_cpp_policies`, through
+  `extra_known_features` or `extra_enabled_features`.
 - QNX toolchains use additional licensing and include-path parameters that do
   not apply to Linux toolchains.

docs/extension_api.md

@@ -51,57 +51,3 @@ cc_test(
     linkstatic = False,
     deps = [":math_lib"],
 )
-
-cc_test(
-    name = "asan_test",
-    srcs = ["asan_test.cpp"],
-    features = ["asan"],
-    deps = [
-        "@googletest//:gtest",
-        "@googletest//:gtest_main",
-    ],
-)
-
-# for some reason this test is very flaky.
-# cc_test(
-#     name = "tsan_test",
-#     srcs = ["tsan_test.cpp"],
-#     features = ["tsan"],
-#     env = {
-#         "TSAN_OPTIONS": "halt_on_error=1",
-#     },
-#     deps = [
-#         "@googletest//:gtest",
-#         "@googletest//:gtest_main",
-#     ],
-# )
-
-cc_test(
-    name = "ubsan_test",
-    srcs = ["ubsan_test.cpp"],
-    env = {
-        "UBSAN_OPTIONS": "halt_on_error=1",
-    },
-    features = ["ubsan"],
-    deps = [
-        "@googletest//:gtest",
-        "@googletest//:gtest_main",
-    ],
-)
-
-cc_test(
-    name = "lsan_test",
-    srcs = ["lsan_test.cpp"],
-    env = {
-        "ASAN_OPTIONS": "detect_leaks=1",
-        "LSAN_OPTIONS": "exitcode=23",
-    },
-    features = [
-        "lsan",
-        "asan",
-    ],
-    deps = [
-        "@googletest//:gtest",
-        "@googletest//:gtest_main",
-    ],
-)

examples/BUILD

@@ -30,7 +30,7 @@ bazel_dep(name = "score_bazel_platforms", version = "0.1.2")
 # *******************************************************************************
 # C++ Rules for Bazel
 # *******************************************************************************
-bazel_dep(name = "rules_cc", version = "0.2.14")
+bazel_dep(name = "rules_cc", version = "0.2.17")
 bazel_dep(name = "googletest", version = "1.17.0")
 
 # *******************************************************************************

examples/MODULE.bazel

@@ -10,6 +10,17 @@ The toolchain configurations are defined in:
 
 ## Building Targets
 
+## Sanitizer Feature Registration
+
+Sanitizer features are no longer included by default by the example toolchain
+declarations. Targets that request features such as `score_asan` require the
+workspace to register those feature definitions explicitly, for example from
+`score_cpp_policies` via `extra_known_features` or `extra_enabled_features` on
+the corresponding `gcc.toolchain(...)` declaration.
+
+Without that explicit registration, sanitizer-specific example targets are not
+expected to build.
+
 ### Default Toolchain
 
 Build a specific target with the default toolchain: