Silence protobuf sun.misc.Unsafe warnings from the direct header comp… - #375
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Silence protobuf sun.misc.Unsafe warnings from the direct header comp…#375davido wants to merge 1 commit into
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TurbineDirect bundles protobuf, whose UnsafeUtil calls terminally-deprecated sun.misc.Unsafe methods. On JDK 24+ (JEP 498), the JVM prints a warning for each such call during header compilation: WARNING: A terminally deprecated method in sun.misc.Unsafe has been called WARNING: sun.misc.Unsafe::arrayBaseOffset has been called by com.google.protobuf.UnsafeUtil The direct header compiler has two invocation shapes. TurbineDirect's deploy jar runs as java -jar, but the prebuilt turbine_direct_graal tools are native binaries. Only the deploy jar can receive JVM options; the native binary parses the same values as Turbine CLI options and fails with: unknown option: --sun-misc-unsafe-memory-access=allow Expose a turbine_direct_jvm_opts java_toolchain attribute so toolchains can pass JVM options to the direct header compiler without reusing turbine_jvm_opts or hard-coding tool-specific policy in java_toolchain.bzl. Set the default toolchain's direct JVM opts only on platforms where //toolchains:turbine_direct falls back to the Java TurbineDirect deploy jar. Leave the option empty where turbine_direct_graal is selected. This select intentionally mirrors the //toolchains:turbine_direct select so the flag is not passed to native direct compilers. Also reject turbine_direct_jvm_opts when header_compiler_direct is a native executable. Without that guard an accidental configuration would reach turbine_direct_graal as Turbine command-line options and fail at execution time with a less clear "unknown option" error. Projects that use a deploy-jar direct header compiler can now set turbine_direct_jvm_opts in their java_toolchain. That setting is typically guarded by the same platform select that chooses the Java TurbineDirect deploy jar over native turbine_direct_graal. Add analysis tests for the new attribute: explicit direct JVM opts reach direct header compilation, no direct opts are injected by default, and regular turbine_jvm_opts do not apply to the direct compiler. Also test that the new attr rejects native direct header compilers. See protocolbuffers/protobuf#20760. Closes bazelbuild#374 Tested: * buildifier java/common/rules/java_toolchain.bzl \ toolchains/default_java_toolchain.bzl \ test/java/toolchains/java_toolchain_tests.bzl * bazelisk test //test/java/toolchains:java_toolchain_tests \ --test_output=errors
davido
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| header_compiler_direct_data = [] | ||
| header_compiler_direct_jvm_opts = [] | ||
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| turbine_direct_jvm_opts = get_internal_java_common().expand_java_opts( |
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Lets not complicate things unnecessarily. Just use the opts as is without expansion for now.
| tokenize = False, | ||
| exec_paths = True, | ||
| ) | ||
| if turbine_direct_jvm_opts and not _is_deploy_jar_tool(ctx.attr.header_compiler_direct): |
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If we're going with a dedicated attribute, I don't think we need to perform all this validation. Lets just pass the user-specified opts as is.
Maybe just a warning note in the attribute docs about graal vs deploy jar.
| The list of arguments for the JVM when invoking turbine. | ||
| """, | ||
| ), | ||
| "turbine_direct_jvm_opts": attr.string_list( |
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For consistency lets call this header_compiler_direct_opts
| "-Xmaxwarns -1", | ||
| ] | ||
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| TURBINE_DIRECT_JAVA_FALLBACK_JVM_OPTS = select({ |
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I don't think this makes sense - the header_compiler_direct is a public attribute and user-settable. Expecting the non-graal executable based on platform isn't correct.
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…iler
turbine_direct (header_compiler_direct) bundles protobuf, whose UnsafeUtil calls terminally-deprecated sun.misc.Unsafe methods. On JDK 24+ (JEP 498) the JVM prints a warning for each such call during header compilation:
WARNING: A terminally deprecated method in sun.misc.Unsafe has been called
WARNING: sun.misc.Unsafe::arrayBaseOffset has been called by
com.google.protobuf.UnsafeUtil (.../java_tools/turbine_direct_binary_deploy.jar)
Unlike the Turbine worker, header_compiler_direct does not receive turbine_jvm_opts, and --jvmopt does not reach header-compilation actions, so a toolchain currently has no way to silence these warnings for the direct header compiler. Add --sun-misc-unsafe-memory-access=allow to header_compiler_direct_jvm_opts, gated on the runtime feature version since the flag is rejected on JDK <= 22.
See protocolbuffers/protobuf#20760.
Closes #374