libclang.so: Make SONAME the same as LLVM version

[tstellar]

Summary

This partially reverts c7b3a91017d26266d7556b1ac7c49b06f0109b91. Having
libclang.so with a different SONAME than the other LLVM libraries was
causing a lot of confusion for users. Also, this change did not really
acheive it's purpose of allowing apps to use newer versions of
libclang.so without rebuilding, because a new version of libclang.so
requires a new version of libLLVM.so, which does not have a stable ABI.

[h-vetinari]

Thanks for the ping. It's unfortunate that this didn't work out as intended. It's certainly fine though (for our purposes) to go back to the way things were before.

[MaskRay]

LGTM. I have seen multiple reports that distributors found this behavior change surprising.
I agree that having this more complex symbol versioning with libclang.so probably doesn't improve things a lot since libclang uses LLVM and the LLVM lib doesn't have API/ABI stability.

[h-vetinari]

Forgot to mention it before: would be good to note this in the release notes

[tstellar]

Add release note.

[tstellar]

@h-vetinari Does the release note look OK?

[h-vetinari]

In D129160#3678431, @tstellar wrote:

@h-vetinari Does the release note look OK?

Basically yes, thank you! I'd still be more precise and say "soversion" rather than "soname", but otherwise OK.

[tstellar]

In D129160#3678441, @h-vetinari wrote:

In D129160#3678431, @tstellar wrote:

@h-vetinari Does the release note look OK?

Basically yes, thank you! I'd still be more precise and say "soversion" rather than "soname", but otherwise OK.

OK, I'll fix that when I commit it.

[isuruf]

As a downstream packager of libclang, I really like the SONAME not changing in libclang. It makes it possible for us to package things like qt that depend on libclang, but not have to rebuild qt for every major revision of LLVM.
It's not clear to me what the reason for removing this is. Can someone help me understand why this useful feature was removed?

[MaskRay]

In D129160#3716016, @isuruf wrote:

As a downstream packager of libclang, I really like the SONAME not changing in libclang. It makes it possible for us to package things like qt that depend on libclang, but not have to rebuild qt for every major revision of LLVM.
It's not clear to me what the reason for removing this is. Can someone help me understand why this useful feature was removed?

Too many users have complained that an unchanged soname may suggest some bugs in the build system.

[isuruf]

Maybe this should be a cmake option that is off by default and I can turn it for my builds?

[h-vetinari]

In D129160#3716826, @isuruf wrote:

Maybe this should be a cmake option that is off by default and I can turn it for my builds?

I proposed something along those lines in https://discourse.llvm.org/t/rationale-for-removing-versioned-libclang-middle-ground-to-keep-it-behind-option/64410

[aaronpuchert]

Also, this change did not really acheive it's purpose of allowing apps to use newer versions of libclang.so without rebuilding, because a new version of libclang.so requires a new version of libLLVM.so, which does not have a stable ABI.

Could you elaborate on this? If an application uses only libclang.so, and that is updated to a newer version using a newer libLLVM.so, why would the application need to be rebuilt? Isn't the C API self-contained?

It was a bit tough to decouple libclang.so packaging-wise, but we released it like that already and reverting now seems to just obsolete efforts that had already happened.

[isuruf]

Could you elaborate on this?

Sure. If an application links to libclang.so when the application is being built, the application will hardcode libclang.so.13 in it and will look for it.
When the SONAME changes to libclang.so.15 in LLVM 15, the application will not be able to use the libclang from LLVM 15 unless the
application was rebuilt with libclang.so in LLVM 15.

[aaronpuchert]

In D129160#3721943, @isuruf wrote:

Sure. If an application links to libclang.so when the application is being built, the application will hardcode libclang.so.13 in it and will look for it.
When the SONAME changes to libclang.so.15 in LLVM 15, the application will not be able to use the libclang from LLVM 15 unless the
application was rebuilt with libclang.so in LLVM 15.

That's the problem after this change, but what was the problem before the change? The commit message (where my quote is from) suggests this wouldn't have worked even if we stayed at libclang.so.13 in LLVM 15.

clang/docs/ReleaseNotes.rst

 
 - clang-extdef-mapping now accepts .ast files as input. This is faster than to
   recompile the files from sources when extracting method definitons. This can
   be really beneficial when creating .ast files for input to the clang-static-analyzer.
 
 libclang
 --------
 
-- ...
+- The soversion for libclang will now change for each new LLVM major release.  This matches
+  the behavior of clang <= 13.
 
 Static Analyzer
 ---------------
 - `New CTU implementation
   <https://discourse.llvm.org/t/rfc-much-faster-cross-translation-unit-ctu-analysis-implementation/61728>`_
   that keeps the slow-down around 2x compared to the single-TU analysis, even
   in case of complex C++ projects. Still, it finds the majority of the "old"
   CTU findings. Besides, not more than ~3% of the bug reports are lost compared

clang/tools/libclang/CMakeLists.txt

-# The SOVERSION should be updated only if a change is made to the libclang
-# ABI, and when it is updated, it should be updated to the current
-# LLVM_VERSION_MAJOR.
-# Please also see clang/tools/libclang/libclang.map
-set(CLANG_SONAME 13)
-
 set(SOURCES
   ARCMigrate.cpp
   BuildSystem.cpp
   CIndex.cpp
   CIndexCXX.cpp
   CIndexCodeCompletion.cpp
   CIndexDiagnostic.cpp
   CIndexHigh.cpp
elseif (CLANG_BUILT_STANDALONE)
   if (DL_LIBRARY_PATH)
     list(APPEND LIBS dl)
   endif ()
 endif ()
 
 option(LIBCLANG_BUILD_STATIC
   "Build libclang as a static library (in addition to a shared one)" OFF)
 
-set(LLVM_EXPORTED_SYMBOL_FILE ${CMAKE_CURRENT_BINARY_DIR}/libclang-generic.exports)
-set(LIBCLANG_VERSION_SCRIPT_FILE ${CMAKE_CURRENT_SOURCE_DIR}/libclang.map)
+set(LLVM_EXPORTED_SYMBOL_FILE ${CMAKE_CURRENT_SOURCE_DIR}/libclang.exports)
 
 if(MSVC)
   # Avoid LNK4197 by not specifying libclang.exports here.
   # Each functions is exported as "dllexport" in include/clang-c.
   # KB835326
   set(LLVM_EXPORTED_SYMBOL_FILE)
 endif()
 
-if (UNIX AND NOT APPLE)
-  set(LLVM_EXPORTED_SYMBOL_FILE)
-  set(USE_VERSION_SCRIPT ${LLVM_HAVE_LINK_VERSION_SCRIPT})
-endif()
-
-if (LLVM_EXPORTED_SYMBOL_FILE)
-  add_custom_command(OUTPUT ${LLVM_EXPORTED_SYMBOL_FILE}
-                     COMMAND "${Python3_EXECUTABLE}"
-                       ARGS ${CMAKE_CURRENT_SOURCE_DIR}/linker-script-to-export-list.py
-                            ${LIBCLANG_VERSION_SCRIPT_FILE}
-                            ${LLVM_EXPORTED_SYMBOL_FILE}
-                     DEPENDS ${LIBCLANG_VERSION_SCRIPT_FILE})
-endif()
-
 if(LLVM_ENABLE_PIC OR (WIN32 AND NOT LIBCLANG_BUILD_STATIC))
   set(ENABLE_SHARED SHARED)
 endif()
 
 if(NOT LLVM_ENABLE_PIC OR LIBCLANG_BUILD_STATIC)
   set(ENABLE_STATIC STATIC)
 endif()
 
set_target_properties(libclang
       DEFINE_SYMBOL _CINDEX_LIB_)
     # FIXME: _CINDEX_LIB_ affects dllexport/dllimport on Win32.
     if(LLVM_ENABLE_MODULES AND NOT WIN32)
       target_compile_options(libclang PRIVATE
         "-fmodules-ignore-macro=_CINDEX_LIB_"
         )
     endif()
   endif()
-  if (USE_VERSION_SCRIPT)
-    target_link_options(libclang PRIVATE "-Wl,--version-script,${CMAKE_CURRENT_SOURCE_DIR}/libclang.map")
-    # The Solaris 11.4 linker supports a subset of GNU ld version scripts,
-    # but requires a special option to enable it.
-    if (${CMAKE_SYSTEM_NAME} MATCHES "SunOS")
-      target_link_options(libclang PRIVATE "-Wl,-z,gnu-version-script-compat")
-    endif()
-    # Ensure that libclang.so gets rebuilt when the linker script changes.
-    set_property(SOURCE ARCMigrate.cpp APPEND PROPERTY
-                 OBJECT_DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/libclang.map)
-
-    set_target_properties(libclang PROPERTIES
-                          VERSION ${LLVM_VERSION_MAJOR}.${LLVM_VERSION_MINOR}.${LLVM_VERSION_PATCH}${LLVM_VERSION_SUFFIX}
-                          SOVERSION ${CLANG_SONAME})
-  endif()
 endif()
 
 if(INTERNAL_INSTALL_PREFIX)
   set(LIBCLANG_HEADERS_INSTALL_DESTINATION "${INTERNAL_INSTALL_PREFIX}/include")
 else()
   set(LIBCLANG_HEADERS_INSTALL_DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}")
 endif()
 

clang/tools/libclang/libclang.exports

+clang_BlockCommandComment_getArgText
+clang_BlockCommandComment_getCommandName
+clang_BlockCommandComment_getNumArgs
+clang_BlockCommandComment_getParagraph
+clang_CXCursorSet_contains
+clang_CXCursorSet_insert
+clang_CXIndex_getGlobalOptions
+clang_CXIndex_setGlobalOptions
+clang_CXIndex_setInvocationEmissionPathOption
+clang_CXRewriter_create
+clang_CXRewriter_dispose
+clang_CXRewriter_insertTextBefore
+clang_CXRewriter_overwriteChangedFiles
+clang_CXRewriter_removeText
+clang_CXRewriter_replaceText
+clang_CXRewriter_writeMainFileToStdOut
+clang_CXXConstructor_isConvertingConstructor
+clang_CXXConstructor_isCopyConstructor
+clang_CXXConstructor_isDefaultConstructor
+clang_CXXConstructor_isMoveConstructor
+clang_CXXField_isMutable
+clang_CXXMethod_isConst
+clang_CXXMethod_isDefaulted
+clang_CXXMethod_isPureVirtual
+clang_CXXMethod_isStatic
+clang_CXXMethod_isVirtual
+clang_CXXRecord_isAbstract
+clang_Comment_getChild
+clang_Comment_getKind
+clang_Comment_getNumChildren
+clang_Comment_isWhitespace
+clang_CompilationDatabase_dispose
+clang_CompilationDatabase_fromDirectory
+clang_CompilationDatabase_getAllCompileCommands
+clang_CompilationDatabase_getCompileCommands
+clang_CompileCommand_getArg
+clang_CompileCommand_getDirectory
+clang_CompileCommand_getFilename
+clang_CompileCommand_getMappedSourceContent
+clang_CompileCommand_getMappedSourcePath
+clang_CompileCommand_getNumArgs
+clang_CompileCommand_getNumMappedSources
+clang_CompileCommands_dispose
+clang_CompileCommands_getCommand
+clang_CompileCommands_getSize
+clang_Cursor_Evaluate
+clang_Cursor_getArgument
+clang_Cursor_getBriefCommentText
+clang_Cursor_getCXXManglings
+clang_Cursor_getCommentRange
+clang_Cursor_getMangling
+clang_Cursor_getModule
+clang_Cursor_getNumArguments
+clang_Cursor_getNumTemplateArguments
+clang_Cursor_getObjCDeclQualifiers
+clang_Cursor_getObjCManglings
+clang_Cursor_getObjCPropertyAttributes
+clang_Cursor_getObjCPropertyGetterName
+clang_Cursor_getObjCPropertySetterName
+clang_Cursor_getObjCSelectorIndex
+clang_Cursor_getOffsetOfField
+clang_Cursor_getParsedComment
+clang_Cursor_getRawCommentText
+clang_Cursor_getReceiverType
+clang_Cursor_getSpellingNameRange
+clang_Cursor_getStorageClass
+clang_Cursor_getTemplateArgumentKind
+clang_Cursor_getTemplateArgumentType
+clang_Cursor_getTemplateArgumentUnsignedValue
+clang_Cursor_getTemplateArgumentValue
+clang_Cursor_getTranslationUnit
+clang_Cursor_getVarDeclInitializer
+clang_Cursor_hasAttrs
+clang_Cursor_hasVarDeclExternalStorage
+clang_Cursor_hasVarDeclGlobalStorage
+clang_Cursor_isAnonymous
+clang_Cursor_isAnonymousRecordDecl
+clang_Cursor_isBitField
+clang_Cursor_isDynamicCall
+clang_Cursor_isExternalSymbol
+clang_Cursor_isFunctionInlined
+clang_Cursor_isInlineNamespace
+clang_Cursor_isMacroBuiltin
+clang_Cursor_isMacroFunctionLike
+clang_Cursor_isNull
+clang_Cursor_isObjCOptional
+clang_Cursor_isVariadic
+clang_EnumDecl_isScoped
+clang_EvalResult_dispose
+clang_EvalResult_getAsDouble
+clang_EvalResult_getAsInt
+clang_EvalResult_getAsLongLong
+clang_EvalResult_getAsStr
+clang_EvalResult_getAsUnsigned
+clang_EvalResult_getKind
+clang_EvalResult_isUnsignedInt
+clang_File_isEqual
+clang_File_tryGetRealPathName
+clang_FullComment_getAsHTML
+clang_FullComment_getAsXML
+clang_HTMLStartTagComment_isSelfClosing
+clang_HTMLStartTag_getAttrName
+clang_HTMLStartTag_getAttrValue
+clang_HTMLStartTag_getNumAttrs
+clang_HTMLTagComment_getAsString
+clang_HTMLTagComment_getTagName
+clang_IndexAction_create
+clang_IndexAction_dispose
+clang_InlineCommandComment_getArgText
+clang_InlineCommandComment_getCommandName
+clang_InlineCommandComment_getNumArgs
+clang_InlineCommandComment_getRenderKind
+clang_InlineContentComment_hasTrailingNewline
+clang_Location_isFromMainFile
+clang_Location_isInSystemHeader
+clang_ModuleMapDescriptor_create
+clang_ModuleMapDescriptor_dispose
+clang_ModuleMapDescriptor_setFrameworkModuleName
+clang_ModuleMapDescriptor_setUmbrellaHeader
+clang_ModuleMapDescriptor_writeToBuffer
+clang_Module_getASTFile
+clang_Module_getFullName
+clang_Module_getName
+clang_Module_getNumTopLevelHeaders
+clang_Module_getParent
+clang_Module_getTopLevelHeader
+clang_Module_isSystem
+clang_ParamCommandComment_getDirection
+clang_ParamCommandComment_getParamIndex
+clang_ParamCommandComment_getParamName
+clang_ParamCommandComment_isDirectionExplicit
+clang_ParamCommandComment_isParamIndexValid
+clang_PrintingPolicy_dispose
+clang_PrintingPolicy_getProperty
+clang_PrintingPolicy_setProperty
+clang_Range_isNull
+clang_TParamCommandComment_getDepth
+clang_TParamCommandComment_getIndex
+clang_TParamCommandComment_getParamName
+clang_TParamCommandComment_isParamPositionValid
+clang_TargetInfo_dispose
+clang_TargetInfo_getPointerWidth
+clang_TargetInfo_getTriple
+clang_TextComment_getText
+clang_Type_getAlignOf
+clang_Type_getCXXRefQualifier
+clang_Type_getClassType
+clang_Type_getModifiedType
+clang_Type_getNamedType
+clang_Type_getNullability
+clang_Type_getNumObjCProtocolRefs
+clang_Type_getNumObjCTypeArgs
+clang_Type_getNumTemplateArguments
+clang_Type_getObjCEncoding
+clang_Type_getObjCObjectBaseType
+clang_Type_getObjCProtocolDecl
+clang_Type_getObjCTypeArg
+clang_Type_getOffsetOf
+clang_Type_getSizeOf
+clang_Type_getTemplateArgumentAsType
+clang_Type_getValueType
+clang_Type_isTransparentTagTypedef
+clang_Type_visitFields
+clang_VerbatimBlockLineComment_getText
+clang_VerbatimLineComment_getText
+clang_VirtualFileOverlay_addFileMapping
+clang_VirtualFileOverlay_create
+clang_VirtualFileOverlay_dispose
+clang_VirtualFileOverlay_setCaseSensitivity
+clang_VirtualFileOverlay_writeToBuffer
+clang_annotateTokens
+clang_codeCompleteAt
+clang_codeCompleteGetContainerKind
+clang_codeCompleteGetContainerUSR
+clang_codeCompleteGetContexts
+clang_codeCompleteGetDiagnostic
+clang_codeCompleteGetNumDiagnostics
+clang_codeCompleteGetObjCSelector
+clang_constructUSR_ObjCCategory
+clang_constructUSR_ObjCClass
+clang_constructUSR_ObjCIvar
+clang_constructUSR_ObjCMethod
+clang_constructUSR_ObjCProperty
+clang_constructUSR_ObjCProtocol
+clang_createCXCursorSet
+clang_createIndex
+clang_createTranslationUnit
+clang_createTranslationUnit2
+clang_createTranslationUnitFromSourceFile
+clang_defaultCodeCompleteOptions
+clang_defaultDiagnosticDisplayOptions
+clang_defaultEditingTranslationUnitOptions
+clang_defaultReparseOptions
+clang_defaultSaveOptions
+clang_disposeCXCursorSet
+clang_disposeCXPlatformAvailability
+clang_disposeCXTUResourceUsage
+clang_disposeCodeCompleteResults
+clang_disposeDiagnostic
+clang_disposeDiagnosticSet
+clang_disposeIndex
+clang_disposeOverriddenCursors
+clang_disposeSourceRangeList
+clang_disposeString
+clang_disposeStringSet
+clang_disposeTokens
+clang_disposeTranslationUnit
+clang_enableStackTraces
+clang_equalCursors
+clang_equalLocations
+clang_equalRanges
+clang_equalTypes
+clang_executeOnThread
+clang_findIncludesInFile
+clang_findIncludesInFileWithBlock
+clang_findReferencesInFile
+clang_findReferencesInFileWithBlock
+clang_formatDiagnostic
+clang_free
+clang_getAddressSpace
+clang_getAllSkippedRanges
+clang_getArgType
+clang_getArrayElementType
+clang_getArraySize
+clang_getBuildSessionTimestamp
+clang_getCString
+clang_getCXTUResourceUsage
+clang_getCXXAccessSpecifier
+clang_getCanonicalCursor
+clang_getCanonicalType
+clang_getChildDiagnostics
+clang_getClangVersion
+clang_getCompletionAnnotation
+clang_getCompletionAvailability
+clang_getCompletionBriefComment
+clang_getCompletionChunkCompletionString
+clang_getCompletionChunkKind
+clang_getCompletionChunkText
+clang_getCompletionFixIt
+clang_getCompletionNumAnnotations
+clang_getCompletionNumFixIts
+clang_getCompletionParent
+clang_getCompletionPriority
+clang_getCursor
+clang_getCursorAvailability
+clang_getCursorCompletionString
+clang_getCursorDefinition
+clang_getCursorDisplayName
+clang_getCursorExceptionSpecificationType
+clang_getCursorExtent
+clang_getCursorKind
+clang_getCursorKindSpelling
+clang_getCursorLanguage
+clang_getCursorLexicalParent
+clang_getCursorLinkage
+clang_getCursorLocation
+clang_getCursorPlatformAvailability
+clang_getCursorPrettyPrinted
+clang_getCursorPrintingPolicy
+clang_getCursorReferenceNameRange
+clang_getCursorReferenced
+clang_getCursorResultType
+clang_getCursorSemanticParent
+clang_getCursorSpelling
+clang_getCursorTLSKind
+clang_getCursorType
+clang_getCursorUSR
+clang_getCursorVisibility
+clang_getDeclObjCTypeEncoding
+clang_getDefinitionSpellingAndExtent
+clang_getDiagnostic
+clang_getDiagnosticCategory
+clang_getDiagnosticCategoryName
+clang_getDiagnosticCategoryText
+clang_getDiagnosticFixIt
+clang_getDiagnosticInSet
+clang_getDiagnosticLocation
+clang_getDiagnosticNumFixIts
+clang_getDiagnosticNumRanges
+clang_getDiagnosticOption
+clang_getDiagnosticRange
+clang_getDiagnosticSetFromTU
+clang_getDiagnosticSeverity
+clang_getDiagnosticSpelling
+clang_getElementType
+clang_getEnumConstantDeclUnsignedValue
+clang_getEnumConstantDeclValue
+clang_getEnumDeclIntegerType
+clang_getExceptionSpecificationType
+clang_getExpansionLocation
+clang_getFieldDeclBitWidth
+clang_getFile
+clang_getFileContents
+clang_getFileLocation
+clang_getFileName
+clang_getFileTime
+clang_getFileUniqueID
+clang_getFunctionTypeCallingConv
+clang_getIBOutletCollectionType
+clang_getIncludedFile
+clang_getInclusions
+clang_getInstantiationLocation
+clang_getLocation
+clang_getLocationForOffset
+clang_getModuleForFile
+clang_getNullCursor
+clang_getNullLocation
+clang_getNullRange
+clang_getNumArgTypes
+clang_getNumCompletionChunks
+clang_getNumDiagnostics
+clang_getNumDiagnosticsInSet
+clang_getNumElements
+clang_getNumOverloadedDecls
+clang_getOverloadedDecl
+clang_getOverriddenCursors
+clang_getPointeeType
+clang_getPresumedLocation
+clang_getRange
+clang_getRangeEnd
+clang_getRangeStart
+clang_getRemappings
+clang_getRemappingsFromFileList
+clang_getResultType
+clang_getSkippedRanges
+clang_getSpecializedCursorTemplate
+clang_getSpellingLocation
+clang_getTUResourceUsageName
+clang_getTemplateCursorKind
+clang_getToken
+clang_getTokenExtent
+clang_getTokenKind
+clang_getTokenLocation
+clang_getTokenSpelling
+clang_getTranslationUnitCursor
+clang_getTranslationUnitSpelling
+clang_getTranslationUnitTargetInfo
+clang_getTypeDeclaration
+clang_getTypeKindSpelling
+clang_getTypeSpelling
+clang_getTypedefDeclUnderlyingType
+clang_getTypedefName
+clang_hashCursor
+clang_indexLoc_getCXSourceLocation
+clang_indexLoc_getFileLocation
+clang_indexSourceFile
+clang_indexSourceFileFullArgv
+clang_indexTranslationUnit
+clang_index_getCXXClassDeclInfo
+clang_index_getClientContainer
+clang_index_getClientEntity
+clang_index_getIBOutletCollectionAttrInfo
+clang_index_getObjCCategoryDeclInfo
+clang_index_getObjCContainerDeclInfo
+clang_index_getObjCInterfaceDeclInfo
+clang_index_getObjCPropertyDeclInfo
+clang_index_getObjCProtocolRefListInfo
+clang_index_isEntityObjCContainerKind
+clang_index_setClientContainer
+clang_index_setClientEntity
+clang_install_aborting_llvm_fatal_error_handler
+clang_isAttribute
+clang_isConstQualifiedType
+clang_isCursorDefinition
+clang_isDeclaration
+clang_isExpression
+clang_isFileMultipleIncludeGuarded
+clang_isFunctionTypeVariadic
+clang_isInvalid
+clang_isInvalidDeclaration
+clang_isPODType
+clang_isPreprocessing
+clang_isReference
+clang_isRestrictQualifiedType
+clang_isStatement
+clang_isTranslationUnit
+clang_isUnexposed
+clang_isVirtualBase
+clang_isVolatileQualifiedType
+clang_loadDiagnostics
+clang_parseTranslationUnit
+clang_parseTranslationUnit2
+clang_parseTranslationUnit2FullArgv
+clang_remap_dispose
+clang_remap_getFilenames
+clang_remap_getNumFiles
+clang_reparseTranslationUnit
+clang_saveTranslationUnit
+clang_sortCodeCompletionResults
+clang_suspendTranslationUnit
+clang_toggleCrashRecovery
+clang_tokenize
+clang_uninstall_llvm_fatal_error_handler
+clang_visitChildren
+clang_visitChildrenWithBlock

clang/tools/libclang/libclang.map

-# If you add a symbol to this file, make sure to add it with the correct
-# version.  For example, if the LLVM main branch is LLVM 14.0.0, add new
-# symbols with the version LLVM_14.
-# On platforms where versions scripts are not used, this file will be used to
-# generate a list of exports for libclang.so
-
-LLVM_13 {
-  global:
-    clang_BlockCommandComment_getArgText;
-    clang_BlockCommandComment_getCommandName;
-    clang_BlockCommandComment_getNumArgs;
-    clang_BlockCommandComment_getParagraph;
-    clang_CXCursorSet_contains;
-    clang_CXCursorSet_insert;
-    clang_CXIndex_getGlobalOptions;
-    clang_CXIndex_setGlobalOptions;
-    clang_CXIndex_setInvocationEmissionPathOption;
-    clang_CXRewriter_create;
-    clang_CXRewriter_dispose;
-    clang_CXRewriter_insertTextBefore;
-    clang_CXRewriter_overwriteChangedFiles;
-    clang_CXRewriter_removeText;
-    clang_CXRewriter_replaceText;
-    clang_CXRewriter_writeMainFileToStdOut;
-    clang_CXXConstructor_isConvertingConstructor;
-    clang_CXXConstructor_isCopyConstructor;
-    clang_CXXConstructor_isDefaultConstructor;
-    clang_CXXConstructor_isMoveConstructor;
-    clang_CXXField_isMutable;
-    clang_CXXMethod_isConst;
-    clang_CXXMethod_isDefaulted;
-    clang_CXXMethod_isPureVirtual;
-    clang_CXXMethod_isStatic;
-    clang_CXXMethod_isVirtual;
-    clang_CXXRecord_isAbstract;
-    clang_Comment_getChild;
-    clang_Comment_getKind;
-    clang_Comment_getNumChildren;
-    clang_Comment_isWhitespace;
-    clang_CompilationDatabase_dispose;
-    clang_CompilationDatabase_fromDirectory;
-    clang_CompilationDatabase_getAllCompileCommands;
-    clang_CompilationDatabase_getCompileCommands;
-    clang_CompileCommand_getArg;
-    clang_CompileCommand_getDirectory;
-    clang_CompileCommand_getFilename;
-    clang_CompileCommand_getMappedSourceContent;
-    clang_CompileCommand_getMappedSourcePath;
-    clang_CompileCommand_getNumArgs;
-    clang_CompileCommand_getNumMappedSources;
-    clang_CompileCommands_dispose;
-    clang_CompileCommands_getCommand;
-    clang_CompileCommands_getSize;
-    clang_Cursor_Evaluate;
-    clang_Cursor_getArgument;
-    clang_Cursor_getBriefCommentText;
-    clang_Cursor_getCXXManglings;
-    clang_Cursor_getCommentRange;
-    clang_Cursor_getMangling;
-    clang_Cursor_getModule;
-    clang_Cursor_getNumArguments;
-    clang_Cursor_getNumTemplateArguments;
-    clang_Cursor_getObjCDeclQualifiers;
-    clang_Cursor_getObjCManglings;
-    clang_Cursor_getObjCPropertyAttributes;
-    clang_Cursor_getObjCPropertyGetterName;
-    clang_Cursor_getObjCPropertySetterName;
-    clang_Cursor_getObjCSelectorIndex;
-    clang_Cursor_getOffsetOfField;
-    clang_Cursor_getParsedComment;
-    clang_Cursor_getRawCommentText;
-    clang_Cursor_getReceiverType;
-    clang_Cursor_getSpellingNameRange;
-    clang_Cursor_getStorageClass;
-    clang_Cursor_getTemplateArgumentKind;
-    clang_Cursor_getTemplateArgumentType;
-    clang_Cursor_getTemplateArgumentUnsignedValue;
-    clang_Cursor_getTemplateArgumentValue;
-    clang_Cursor_getTranslationUnit;
-    clang_Cursor_getVarDeclInitializer;
-    clang_Cursor_hasAttrs;
-    clang_Cursor_hasVarDeclExternalStorage;
-    clang_Cursor_hasVarDeclGlobalStorage;
-    clang_Cursor_isAnonymous;
-    clang_Cursor_isAnonymousRecordDecl;
-    clang_Cursor_isBitField;
-    clang_Cursor_isDynamicCall;
-    clang_Cursor_isExternalSymbol;
-    clang_Cursor_isFunctionInlined;
-    clang_Cursor_isInlineNamespace;
-    clang_Cursor_isMacroBuiltin;
-    clang_Cursor_isMacroFunctionLike;
-    clang_Cursor_isNull;
-    clang_Cursor_isObjCOptional;
-    clang_Cursor_isVariadic;
-    clang_EnumDecl_isScoped;
-    clang_EvalResult_dispose;
-    clang_EvalResult_getAsDouble;
-    clang_EvalResult_getAsInt;
-    clang_EvalResult_getAsLongLong;
-    clang_EvalResult_getAsStr;
-    clang_EvalResult_getAsUnsigned;
-    clang_EvalResult_getKind;
-    clang_EvalResult_isUnsignedInt;
-    clang_File_isEqual;
-    clang_File_tryGetRealPathName;
-    clang_FullComment_getAsHTML;
-    clang_FullComment_getAsXML;
-    clang_HTMLStartTagComment_isSelfClosing;
-    clang_HTMLStartTag_getAttrName;
-    clang_HTMLStartTag_getAttrValue;
-    clang_HTMLStartTag_getNumAttrs;
-    clang_HTMLTagComment_getAsString;
-    clang_HTMLTagComment_getTagName;
-    clang_IndexAction_create;
-    clang_IndexAction_dispose;
-    clang_InlineCommandComment_getArgText;
-    clang_InlineCommandComment_getCommandName;
-    clang_InlineCommandComment_getNumArgs;
-    clang_InlineCommandComment_getRenderKind;
-    clang_InlineContentComment_hasTrailingNewline;
-    clang_Location_isFromMainFile;
-    clang_Location_isInSystemHeader;
-    clang_ModuleMapDescriptor_create;
-    clang_ModuleMapDescriptor_dispose;
-    clang_ModuleMapDescriptor_setFrameworkModuleName;
-    clang_ModuleMapDescriptor_setUmbrellaHeader;
-    clang_ModuleMapDescriptor_writeToBuffer;
-    clang_Module_getASTFile;
-    clang_Module_getFullName;
-    clang_Module_getName;
-    clang_Module_getNumTopLevelHeaders;
-    clang_Module_getParent;
-    clang_Module_getTopLevelHeader;
-    clang_Module_isSystem;
-    clang_ParamCommandComment_getDirection;
-    clang_ParamCommandComment_getParamIndex;
-    clang_ParamCommandComment_getParamName;
-    clang_ParamCommandComment_isDirectionExplicit;
-    clang_ParamCommandComment_isParamIndexValid;
-    clang_PrintingPolicy_dispose;
-    clang_PrintingPolicy_getProperty;
-    clang_PrintingPolicy_setProperty;
-    clang_Range_isNull;
-    clang_TParamCommandComment_getDepth;
-    clang_TParamCommandComment_getIndex;
-    clang_TParamCommandComment_getParamName;
-    clang_TParamCommandComment_isParamPositionValid;
-    clang_TargetInfo_dispose;
-    clang_TargetInfo_getPointerWidth;
-    clang_TargetInfo_getTriple;
-    clang_TextComment_getText;
-    clang_Type_getAlignOf;
-    clang_Type_getCXXRefQualifier;
-    clang_Type_getClassType;
-    clang_Type_getModifiedType;
-    clang_Type_getNamedType;
-    clang_Type_getNullability;
-    clang_Type_getNumObjCProtocolRefs;
-    clang_Type_getNumObjCTypeArgs;
-    clang_Type_getNumTemplateArguments;
-    clang_Type_getObjCEncoding;
-    clang_Type_getObjCObjectBaseType;
-    clang_Type_getObjCProtocolDecl;
-    clang_Type_getObjCTypeArg;
-    clang_Type_getOffsetOf;
-    clang_Type_getSizeOf;
-    clang_Type_getTemplateArgumentAsType;
-    clang_Type_getValueType;
-    clang_Type_isTransparentTagTypedef;
-    clang_Type_visitFields;
-    clang_VerbatimBlockLineComment_getText;
-    clang_VerbatimLineComment_getText;
-    clang_VirtualFileOverlay_addFileMapping;
-    clang_VirtualFileOverlay_create;
-    clang_VirtualFileOverlay_dispose;
-    clang_VirtualFileOverlay_setCaseSensitivity;
-    clang_VirtualFileOverlay_writeToBuffer;
-    clang_annotateTokens;
-    clang_codeCompleteAt;
-    clang_codeCompleteGetContainerKind;
-    clang_codeCompleteGetContainerUSR;
-    clang_codeCompleteGetContexts;
-    clang_codeCompleteGetDiagnostic;
-    clang_codeCompleteGetNumDiagnostics;
-    clang_codeCompleteGetObjCSelector;
-    clang_constructUSR_ObjCCategory;
-    clang_constructUSR_ObjCClass;
-    clang_constructUSR_ObjCIvar;
-    clang_constructUSR_ObjCMethod;
-    clang_constructUSR_ObjCProperty;
-    clang_constructUSR_ObjCProtocol;
-    clang_createCXCursorSet;
-    clang_createIndex;
-    clang_createTranslationUnit;
-    clang_createTranslationUnit2;
-    clang_createTranslationUnitFromSourceFile;
-    clang_defaultCodeCompleteOptions;
-    clang_defaultDiagnosticDisplayOptions;
-    clang_defaultEditingTranslationUnitOptions;
-    clang_defaultReparseOptions;
-    clang_defaultSaveOptions;
-    clang_disposeCXCursorSet;
-    clang_disposeCXPlatformAvailability;
-    clang_disposeCXTUResourceUsage;
-    clang_disposeCodeCompleteResults;
-    clang_disposeDiagnostic;
-    clang_disposeDiagnosticSet;
-    clang_disposeIndex;
-    clang_disposeOverriddenCursors;
-    clang_disposeSourceRangeList;
-    clang_disposeString;
-    clang_disposeStringSet;
-    clang_disposeTokens;
-    clang_disposeTranslationUnit;
-    clang_enableStackTraces;
-    clang_equalCursors;
-    clang_equalLocations;
-    clang_equalRanges;
-    clang_equalTypes;
-    clang_executeOnThread;
-    clang_findIncludesInFile;
-    clang_findIncludesInFileWithBlock;
-    clang_findReferencesInFile;
-    clang_findReferencesInFileWithBlock;
-    clang_formatDiagnostic;
-    clang_free;
-    clang_getAddressSpace;
-    clang_getAllSkippedRanges;
-    clang_getArgType;
-    clang_getArrayElementType;
-    clang_getArraySize;
-    clang_getBuildSessionTimestamp;
-    clang_getCString;
-    clang_getCXTUResourceUsage;
-    clang_getCXXAccessSpecifier;
-    clang_getCanonicalCursor;
-    clang_getCanonicalType;
-    clang_getChildDiagnostics;
-    clang_getClangVersion;
-    clang_getCompletionAnnotation;
-    clang_getCompletionAvailability;
-    clang_getCompletionBriefComment;
-    clang_getCompletionChunkCompletionString;
-    clang_getCompletionChunkKind;
-    clang_getCompletionChunkText;
-    clang_getCompletionFixIt;
-    clang_getCompletionNumAnnotations;
-    clang_getCompletionNumFixIts;
-    clang_getCompletionParent;
-    clang_getCompletionPriority;
-    clang_getCursor;
-    clang_getCursorAvailability;
-    clang_getCursorCompletionString;
-    clang_getCursorDefinition;
-    clang_getCursorDisplayName;
-    clang_getCursorExceptionSpecificationType;
-    clang_getCursorExtent;
-    clang_getCursorKind;
-    clang_getCursorKindSpelling;
-    clang_getCursorLanguage;
-    clang_getCursorLexicalParent;
-    clang_getCursorLinkage;
-    clang_getCursorLocation;
-    clang_getCursorPlatformAvailability;
-    clang_getCursorPrettyPrinted;
-    clang_getCursorPrintingPolicy;
-    clang_getCursorReferenceNameRange;
-    clang_getCursorReferenced;
-    clang_getCursorResultType;
-    clang_getCursorSemanticParent;
-    clang_getCursorSpelling;
-    clang_getCursorTLSKind;
-    clang_getCursorType;
-    clang_getCursorUSR;
-    clang_getCursorVisibility;
-    clang_getDeclObjCTypeEncoding;
-    clang_getDefinitionSpellingAndExtent;
-    clang_getDiagnostic;
-    clang_getDiagnosticCategory;
-    clang_getDiagnosticCategoryName;
-    clang_getDiagnosticCategoryText;
-    clang_getDiagnosticFixIt;
-    clang_getDiagnosticInSet;
-    clang_getDiagnosticLocation;
-    clang_getDiagnosticNumFixIts;
-    clang_getDiagnosticNumRanges;
-    clang_getDiagnosticOption;
-    clang_getDiagnosticRange;
-    clang_getDiagnosticSetFromTU;
-    clang_getDiagnosticSeverity;
-    clang_getDiagnosticSpelling;
-    clang_getElementType;
-    clang_getEnumConstantDeclUnsignedValue;
-    clang_getEnumConstantDeclValue;
-    clang_getEnumDeclIntegerType;
-    clang_getExceptionSpecificationType;
-    clang_getExpansionLocation;
-    clang_getFieldDeclBitWidth;
-    clang_getFile;
-    clang_getFileContents;
-    clang_getFileLocation;
-    clang_getFileName;
-    clang_getFileTime;
-    clang_getFileUniqueID;
-    clang_getFunctionTypeCallingConv;
-    clang_getIBOutletCollectionType;
-    clang_getIncludedFile;
-    clang_getInclusions;
-    clang_getInstantiationLocation;
-    clang_getLocation;
-    clang_getLocationForOffset;
-    clang_getModuleForFile;
-    clang_getNullCursor;
-    clang_getNullLocation;
-    clang_getNullRange;
-    clang_getNumArgTypes;
-    clang_getNumCompletionChunks;
-    clang_getNumDiagnostics;
-    clang_getNumDiagnosticsInSet;
-    clang_getNumElements;
-    clang_getNumOverloadedDecls;
-    clang_getOverloadedDecl;
-    clang_getOverriddenCursors;
-    clang_getPointeeType;
-    clang_getPresumedLocation;
-    clang_getRange;
-    clang_getRangeEnd;
-    clang_getRangeStart;
-    clang_getRemappings;
-    clang_getRemappingsFromFileList;
-    clang_getResultType;
-    clang_getSkippedRanges;
-    clang_getSpecializedCursorTemplate;
-    clang_getSpellingLocation;
-    clang_getTUResourceUsageName;
-    clang_getTemplateCursorKind;
-    clang_getToken;
-    clang_getTokenExtent;
-    clang_getTokenKind;
-    clang_getTokenLocation;
-    clang_getTokenSpelling;
-    clang_getTranslationUnitCursor;
-    clang_getTranslationUnitSpelling;
-    clang_getTranslationUnitTargetInfo;
-    clang_getTypeDeclaration;
-    clang_getTypeKindSpelling;
-    clang_getTypeSpelling;
-    clang_getTypedefDeclUnderlyingType;
-    clang_getTypedefName;
-    clang_hashCursor;
-    clang_indexLoc_getCXSourceLocation;
-    clang_indexLoc_getFileLocation;
-    clang_indexSourceFile;
-    clang_indexSourceFileFullArgv;
-    clang_indexTranslationUnit;
-    clang_index_getCXXClassDeclInfo;
-    clang_index_getClientContainer;
-    clang_index_getClientEntity;
-    clang_index_getIBOutletCollectionAttrInfo;
-    clang_index_getObjCCategoryDeclInfo;
-    clang_index_getObjCContainerDeclInfo;
-    clang_index_getObjCInterfaceDeclInfo;
-    clang_index_getObjCPropertyDeclInfo;
-    clang_index_getObjCProtocolRefListInfo;
-    clang_index_isEntityObjCContainerKind;
-    clang_index_setClientContainer;
-    clang_index_setClientEntity;
-    clang_install_aborting_llvm_fatal_error_handler;
-    clang_isAttribute;
-    clang_isConstQualifiedType;
-    clang_isCursorDefinition;
-    clang_isDeclaration;
-    clang_isExpression;
-    clang_isFileMultipleIncludeGuarded;
-    clang_isFunctionTypeVariadic;
-    clang_isInvalid;
-    clang_isInvalidDeclaration;
-    clang_isPODType;
-    clang_isPreprocessing;
-    clang_isReference;
-    clang_isRestrictQualifiedType;
-    clang_isStatement;
-    clang_isTranslationUnit;
-    clang_isUnexposed;
-    clang_isVirtualBase;
-    clang_isVolatileQualifiedType;
-    clang_loadDiagnostics;
-    clang_parseTranslationUnit;
-    clang_parseTranslationUnit2;
-    clang_parseTranslationUnit2FullArgv;
-    clang_remap_dispose;
-    clang_remap_getFilenames;
-    clang_remap_getNumFiles;
-    clang_reparseTranslationUnit;
-    clang_saveTranslationUnit;
-    clang_sortCodeCompletionResults;
-    clang_suspendTranslationUnit;
-    clang_toggleCrashRecovery;
-    clang_tokenize;
-    clang_uninstall_llvm_fatal_error_handler;
-    clang_visitChildren;
-    clang_visitChildrenWithBlock;
-
-  local: *;
-};
-
-# Example of how to add a new symbol version entry.  If you do add a new symbol
-# version, please update the example to depend on the version you added.
-# LLVM_X {
-# global:
-#   clang_newsymbol;
-# };

clang/tools/libclang/linker-script-to-export-list.py

-import re
-import os
-import sys
-
-input_file = open(sys.argv[1])
-output_file = open(sys.argv[2], 'w')
-
-for line in input_file:
-    m = re.search('^\s+(clang_[^;]+)', line)
-    if m:
-        output_file.write(m.group(1) + "\n")