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Merge commit 'c36d7fd568a5' from llvm.org/release/19.x into stable/20240723
2 parents a939acd + c36d7fd commit c9d9b33

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‎libcxx/lib/abi/CHANGELOG.TXT

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@@ -16,6 +16,36 @@ New entries should be added directly below the "Version" header.
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Version 19.0
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------------
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* [libc++] Avoid re-exporting a few specific symbols from libc++abi
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In 6a884a9aef39, I synchronized the export list of libc++abi to the
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export list of libc++. From the linker's perspective, this caused
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these symbols to be taken from libc++.dylib instead of libc++abi.dylib.
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However, that can be problematic when back-deploying. Indeed, this means
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that the linker will encode an undefined reference to be fullfilled by
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libc++.dylib, but when backdeploying against an older system, that symbol
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might only be available in libc++abi.dylib.
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Most of the symbols that started being re-exported after 6a884a9aef39
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turn out to be implementation details of libc++abi, so nobody really
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depends on them and this back-deployment issue is inconsequential.
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However, we ran into issues with a few of these symbols while testing
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LLVM 19, which led to this patch.
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In the future, a follow-up cleanup would be to stop exporting most of
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the _cxxabiv1_foo_type_infoE symbols from both libc++abi and libc++
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since they are implementation details that nobody should be relying
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on.
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<arch>-apple-darwin
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-------------------
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Symbol not reexported anymore: ___cxa_rethrow_primary_exception
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Symbol not reexported anymore: __ZTIN10__cxxabiv117__class_type_infoE
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Symbol not reexported anymore: __ZTIN10__cxxabiv120__si_class_type_infoE
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Symbol not reexported anymore: __ZTIN10__cxxabiv121__vmi_class_type_infoE
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* [libc++] Always keep libc++abi re-exports up-to-date
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This patch makes sure that the set of libc++abi symbols re-exported from libc++

‎libcxx/lib/abi/arm64-apple-darwin.libcxxabi.v1.stable.exceptions.nonew.abilist

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@@ -78,12 +78,9 @@
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{'is_defined': False, 'name': '__ZTIN10__cxxabiv116__enum_type_infoE', 'type': 'U'}
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{'is_defined': False, 'name': '__ZTIN10__cxxabiv116__shim_type_infoE', 'type': 'U'}
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{'is_defined': False, 'name': '__ZTIN10__cxxabiv117__array_type_infoE', 'type': 'U'}
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{'is_defined': False, 'name': '__ZTIN10__cxxabiv117__class_type_infoE', 'type': 'U'}
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{'is_defined': False, 'name': '__ZTIN10__cxxabiv117__pbase_type_infoE', 'type': 'U'}
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{'is_defined': False, 'name': '__ZTIN10__cxxabiv119__pointer_type_infoE', 'type': 'U'}
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{'is_defined': False, 'name': '__ZTIN10__cxxabiv120__function_type_infoE', 'type': 'U'}
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{'is_defined': False, 'name': '__ZTIN10__cxxabiv120__si_class_type_infoE', 'type': 'U'}
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{'is_defined': False, 'name': '__ZTIN10__cxxabiv121__vmi_class_type_infoE', 'type': 'U'}
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{'is_defined': False, 'name': '__ZTIN10__cxxabiv123__fundamental_type_infoE', 'type': 'U'}
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{'is_defined': False, 'name': '__ZTIN10__cxxabiv129__pointer_to_member_type_infoE', 'type': 'U'}
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{'is_defined': False, 'name': '__ZTIPDh', 'type': 'U'}
@@ -2002,12 +1999,9 @@
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{'is_defined': True, 'name': '__ZTIN10__cxxabiv116__enum_type_infoE', 'type': 'I'}
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{'is_defined': True, 'name': '__ZTIN10__cxxabiv116__shim_type_infoE', 'type': 'I'}
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{'is_defined': True, 'name': '__ZTIN10__cxxabiv117__array_type_infoE', 'type': 'I'}
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{'is_defined': True, 'name': '__ZTIN10__cxxabiv117__class_type_infoE', 'type': 'I'}
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{'is_defined': True, 'name': '__ZTIN10__cxxabiv117__pbase_type_infoE', 'type': 'I'}
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{'is_defined': True, 'name': '__ZTIN10__cxxabiv119__pointer_type_infoE', 'type': 'I'}
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{'is_defined': True, 'name': '__ZTIN10__cxxabiv120__function_type_infoE', 'type': 'I'}
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{'is_defined': True, 'name': '__ZTIN10__cxxabiv120__si_class_type_infoE', 'type': 'I'}
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{'is_defined': True, 'name': '__ZTIN10__cxxabiv121__vmi_class_type_infoE', 'type': 'I'}
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{'is_defined': True, 'name': '__ZTIN10__cxxabiv123__fundamental_type_infoE', 'type': 'I'}
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{'is_defined': True, 'name': '__ZTIN10__cxxabiv129__pointer_to_member_type_infoE', 'type': 'I'}
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{'is_defined': True, 'name': '__ZTINSt12experimental15fundamentals_v112bad_any_castE', 'size': 0, 'type': 'OBJECT'}
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{'is_defined': True, 'name': '___cxa_new_handler', 'type': 'I'}
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{'is_defined': True, 'name': '___cxa_pure_virtual', 'type': 'I'}
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{'is_defined': True, 'name': '___cxa_rethrow', 'type': 'I'}
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{'is_defined': True, 'name': '___cxa_rethrow_primary_exception', 'type': 'I'}
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{'is_defined': True, 'name': '___cxa_terminate_handler', 'type': 'I'}
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{'is_defined': True, 'name': '___cxa_throw', 'type': 'I'}
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{'is_defined': True, 'name': '___cxa_throw_bad_array_new_length', 'type': 'I'}

‎libcxx/lib/abi/x86_64-apple-darwin.libcxxabi.v1.stable.exceptions.nonew.abilist

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{'is_defined': False, 'name': '__ZTIN10__cxxabiv116__enum_type_infoE', 'type': 'U'}
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{'is_defined': False, 'name': '__ZTIN10__cxxabiv116__shim_type_infoE', 'type': 'U'}
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{'is_defined': False, 'name': '__ZTIN10__cxxabiv117__array_type_infoE', 'type': 'U'}
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{'is_defined': False, 'name': '__ZTIN10__cxxabiv117__class_type_infoE', 'type': 'U'}
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{'is_defined': False, 'name': '__ZTIN10__cxxabiv117__pbase_type_infoE', 'type': 'U'}
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{'is_defined': False, 'name': '__ZTIN10__cxxabiv119__pointer_type_infoE', 'type': 'U'}
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{'is_defined': False, 'name': '__ZTIN10__cxxabiv120__function_type_infoE', 'type': 'U'}
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{'is_defined': False, 'name': '__ZTIN10__cxxabiv120__si_class_type_infoE', 'type': 'U'}
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{'is_defined': False, 'name': '__ZTIN10__cxxabiv121__vmi_class_type_infoE', 'type': 'U'}
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{'is_defined': False, 'name': '__ZTIN10__cxxabiv123__fundamental_type_infoE', 'type': 'U'}
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{'is_defined': False, 'name': '__ZTIN10__cxxabiv129__pointer_to_member_type_infoE', 'type': 'U'}
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{'is_defined': False, 'name': '__ZTIPDh', 'type': 'U'}
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{'is_defined': True, 'name': '__ZTIN10__cxxabiv116__enum_type_infoE', 'type': 'I'}
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{'is_defined': True, 'name': '__ZTIN10__cxxabiv116__shim_type_infoE', 'type': 'I'}
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{'is_defined': True, 'name': '__ZTIN10__cxxabiv117__array_type_infoE', 'type': 'I'}
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{'is_defined': True, 'name': '__ZTIN10__cxxabiv117__class_type_infoE', 'type': 'I'}
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{'is_defined': True, 'name': '__ZTIN10__cxxabiv117__pbase_type_infoE', 'type': 'I'}
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{'is_defined': True, 'name': '__ZTIN10__cxxabiv119__pointer_type_infoE', 'type': 'I'}
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{'is_defined': True, 'name': '__ZTIN10__cxxabiv120__function_type_infoE', 'type': 'I'}
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{'is_defined': True, 'name': '__ZTIN10__cxxabiv120__si_class_type_infoE', 'type': 'I'}
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{'is_defined': True, 'name': '__ZTIN10__cxxabiv121__vmi_class_type_infoE', 'type': 'I'}
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{'is_defined': True, 'name': '__ZTIN10__cxxabiv123__fundamental_type_infoE', 'type': 'I'}
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{'is_defined': True, 'name': '__ZTIN10__cxxabiv129__pointer_to_member_type_infoE', 'type': 'I'}
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{'is_defined': True, 'name': '__ZTINSt12experimental15fundamentals_v112bad_any_castE', 'size': 0, 'type': 'OBJECT'}
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{'is_defined': True, 'name': '___cxa_new_handler', 'type': 'I'}
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{'is_defined': True, 'name': '___cxa_pure_virtual', 'type': 'I'}
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{'is_defined': True, 'name': '___cxa_rethrow', 'type': 'I'}
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{'is_defined': True, 'name': '___cxa_rethrow_primary_exception', 'type': 'I'}
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{'is_defined': True, 'name': '___cxa_terminate_handler', 'type': 'I'}
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{'is_defined': True, 'name': '___cxa_throw', 'type': 'I'}
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{'is_defined': True, 'name': '___cxa_throw_bad_array_new_length', 'type': 'I'}

‎libcxxabi/lib/cxxabiv1.exp

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__ZTIN10__cxxabiv116__enum_type_infoE
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__ZTIN10__cxxabiv116__shim_type_infoE
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__ZTIN10__cxxabiv117__array_type_infoE
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__ZTIN10__cxxabiv117__class_type_infoE
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__ZTIN10__cxxabiv117__pbase_type_infoE
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__ZTIN10__cxxabiv119__pointer_type_infoE
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__ZTIN10__cxxabiv120__function_type_infoE
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__ZTIN10__cxxabiv120__si_class_type_infoE
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__ZTIN10__cxxabiv121__vmi_class_type_infoE
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__ZTIN10__cxxabiv123__fundamental_type_infoE
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__ZTIN10__cxxabiv129__pointer_to_member_type_infoE
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‎libcxxabi/lib/itanium-base.exp

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@@ -12,7 +12,6 @@ ___cxa_guard_acquire
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___cxa_guard_release
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___cxa_increment_exception_refcount
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___cxa_pure_virtual
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___cxa_rethrow_primary_exception
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___cxa_throw_bad_array_new_length
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___cxa_uncaught_exception
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___cxa_uncaught_exceptions

‎libcxxabi/lib/symbols-not-reexported.exp

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# These symbols are not re-exported from libc++ because providing a definition in libc++ causes
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# issues with some clients when backdeploying.
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# These symbols are implementation details of libc++abi, but they are referenced from UBSan
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# (which is a total hack). We'll need to figure out how to decouple UBSan from these details
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# before we can stop exporting them from libc++abi.
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__ZTIN10__cxxabiv117__class_type_infoE
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__ZTIN10__cxxabiv120__si_class_type_infoE
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__ZTIN10__cxxabiv121__vmi_class_type_infoE
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# This symbol is not an implementation detail of libc++abi, but it also causes issues when moving
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# to libc++. This needs further investigation.
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___cxa_rethrow_primary_exception

‎libcxxabi/src/CMakeLists.txt

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@@ -214,14 +214,22 @@ if (LIBCXXABI_ENABLE_SHARED)
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endif()
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add_library(cxxabi-reexports INTERFACE)
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function(reexport_symbols file)
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function(export_symbols file)
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# -exported_symbols_list is only available on Apple platforms
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if (APPLE)
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target_link_libraries(cxxabi_shared PRIVATE "-Wl,-exported_symbols_list,${file}")
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endif()
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endfunction()
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function(reexport_symbols file)
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export_symbols("${file}")
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# -reexported_symbols_list is only available on Apple platforms
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if (APPLE)
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target_link_libraries(cxxabi-reexports INTERFACE "-Wl,-reexported_symbols_list,${file}")
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endif()
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endfunction()
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export_symbols("${CMAKE_CURRENT_SOURCE_DIR}/../lib/symbols-not-reexported.exp")
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reexport_symbols("${CMAKE_CURRENT_SOURCE_DIR}/../lib/cxxabiv1.exp")
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reexport_symbols("${CMAKE_CURRENT_SOURCE_DIR}/../lib/fundamental-types.exp")
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reexport_symbols("${CMAKE_CURRENT_SOURCE_DIR}/../lib/itanium-base.exp")

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