From 93a9872a669afc859f639a78b3f1cba050f58db0 Mon Sep 17 00:00:00 2001 From: Richard Belleville Date: Tue, 15 Dec 2020 15:40:23 -0800 Subject: [PATCH] Merge pull request #24992 from gnossen/fix_grpc_tools_so_mac_symbols Fix visibility of libprotobuf symbols in protoc_compiler.so on Mac --- tools/distrib/python/grpcio_tools/setup.py | 28 ++++++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/tools/distrib/python/grpcio_tools/setup.py b/tools/distrib/python/grpcio_tools/setup.py index 164088bf7bfaa..a316038d05d3c 100644 --- a/tools/distrib/python/grpcio_tools/setup.py +++ b/tools/distrib/python/grpcio_tools/setup.py @@ -44,6 +44,12 @@ import protoc_lib_deps import grpc_version +_EXT_INIT_SYMBOL = None +if sys.version_info[0] == 2: + _EXT_INIT_SYMBOL = "init_protoc_compiler" +else: + _EXT_INIT_SYMBOL = "PyInit__protoc_compiler" + _parallel_compile_patch.monkeypatch_compile_maybe() CLASSIFIERS = [ @@ -118,6 +124,28 @@ def check_linker_need_libatomic(): EXTRA_ENV_COMPILE_ARGS += ' -fno-wrapv -frtti' if EXTRA_ENV_LINK_ARGS is None: EXTRA_ENV_LINK_ARGS = '' + # NOTE(rbellevi): Clang on Mac OS will make all static symbols (both + # variables and objects) global weak symbols. When a process loads the + # protobuf wheel's shared object library before loading *this* C extension, + # the runtime linker will prefer the protobuf module's version of symbols. + # This results in the process using a mixture of symbols from the protobuf + # wheel and this wheel, which may be using different versions of + # libprotobuf. In the case that they *are* using different versions of + # libprotobuf *and* there has been a change in data layout (or in other + # invariants) segfaults, data corruption, or "bad things" may happen. + # + # This flag ensures that on Mac, the only global symbol is the one loaded by + # the Python interpreter. The problematic global weak symbols become local + # weak symbols. This is not required on Linux since the compiler does not + # produce global weak symbols. This is not required on Windows as our ".pyd" + # file does not contain any symbols. + # + # Finally, the leading underscore here is part of the Mach-O ABI. Unlike + # more modern ABIs (ELF et al.), Mach-O prepends an underscore to the names + # of C functions. + if "darwin" in sys.platform: + EXTRA_ENV_LINK_ARGS += ' -Wl,-exported_symbol,_{}'.format( + _EXT_INIT_SYMBOL) if "linux" in sys.platform or "darwin" in sys.platform: EXTRA_ENV_LINK_ARGS += ' -lpthread' if check_linker_need_libatomic():