CMake: Make most target symbols hidden by default

Summary:
For builds with LLVM_BUILD_LLVM_DYLIB=ON and BUILD_SHARED_LIBS=OFF
this change makes all symbols in the target specific libraries hidden
by default.

A new macro called LLVM_EXTERNAL_VISIBILITY has been added to mark symbols in these
libraries public, which is mainly needed for the definitions of the
LLVMInitialize* functions.

This patch reduces the number of public symbols in libLLVM.so by about
25%.  This should improve load times for the dynamic library and also
make abi checker tools, like abidiff require less memory when analyzing
libLLVM.so

One side-effect of this change is that for builds with
LLVM_BUILD_LLVM_DYLIB=ON and LLVM_LINK_LLVM_DYLIB=ON some unittests that
access symbols that are no longer public will need to be statically linked.

Before and after public symbol counts (using gcc 8.2.1, ld.bfd 2.31.1):
nm before/libLLVM-9svn.so | grep ' [A-Zuvw] ' | wc -l
36221
nm after/libLLVM-9svn.so | grep ' [A-Zuvw] ' | wc -l
26278

Reviewers: chandlerc, beanz, mgorny, rnk, hans

Reviewed By: rnk, hans

Subscribers: merge_guards_bot, luismarques, smeenai, ldionne, lenary, s.egerton, pzheng, sameer.abuasal, MaskRay, wuzish, echristo, Jim, hiraditya, michaelplatings, chapuni, jholewinski, arsenm, dschuff, jyknight, dylanmckay, sdardis, nemanjai, jvesely, javed.absar, sbc100, jgravelle-google, aheejin, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, zzheng, edward-jones, mgrang, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, kristina, jsji, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D54439

include/llvm/Support/Compiler.h

@@ -117,11 +117,17 @@
 /// not accessible from outside it.  Can also be used to mark variables and
 /// functions, making them private to any shared library they are linked into.
 /// On PE/COFF targets, library visibility is the default, so this isn't needed.
+///
+/// LLVM_EXTERNAL_VISIBILITY - classes, functions, and variables marked with
+/// this attribute will be made public and visible outside of any shared library
+/// they are linked in to.
 #if (__has_attribute(visibility) || LLVM_GNUC_PREREQ(4, 0, 0)) &&              \
     !defined(__MINGW32__) && !defined(__CYGWIN__) && !defined(_WIN32)
 #define LLVM_LIBRARY_VISIBILITY __attribute__ ((visibility("hidden")))
+#define LLVM_EXTERNAL_VISIBILITY __attribute__ ((visibility("default")))
 #else
 #define LLVM_LIBRARY_VISIBILITY
+#define LLVM_EXTERNAL_VISIBILITY
 #endif
 
 #if defined(__GNUC__)

lib/Target/AArch64/AArch64AsmPrinter.cpp

@@ -1298,7 +1298,7 @@ void AArch64AsmPrinter::EmitInstruction(const MachineInstr *MI) {
 }
 
 // Force static initialization.
-extern "C" void LLVMInitializeAArch64AsmPrinter() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeAArch64AsmPrinter() {
   RegisterAsmPrinter<AArch64AsmPrinter> X(getTheAArch64leTarget());
   RegisterAsmPrinter<AArch64AsmPrinter> Y(getTheAArch64beTarget());
   RegisterAsmPrinter<AArch64AsmPrinter> Z(getTheARM64Target());

lib/Target/AArch64/AArch64TargetMachine.cpp

@@ -154,7 +154,7 @@ static cl::opt<bool>
                         cl::desc("Enable the AAcrh64 branch target pass"),
                         cl::init(true));
 
-extern "C" void LLVMInitializeAArch64Target() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeAArch64Target() {
   // Register the target.
   RegisterTargetMachine<AArch64leTargetMachine> X(getTheAArch64leTarget());
   RegisterTargetMachine<AArch64beTargetMachine> Y(getTheAArch64beTarget());

lib/Target/AArch64/AsmParser/AArch64AsmParser.cpp

@@ -5515,7 +5515,7 @@ AArch64AsmParser::classifySymbolRef(const MCExpr *Expr,
 }
 
 /// Force static initialization.
-extern "C" void LLVMInitializeAArch64AsmParser() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeAArch64AsmParser() {
   RegisterMCAsmParser<AArch64AsmParser> X(getTheAArch64leTarget());
   RegisterMCAsmParser<AArch64AsmParser> Y(getTheAArch64beTarget());
   RegisterMCAsmParser<AArch64AsmParser> Z(getTheARM64Target());

lib/Target/AArch64/Disassembler/AArch64Disassembler.cpp

@@ -277,7 +277,7 @@ createAArch64ExternalSymbolizer(const Triple &TT, LLVMOpInfoCallback GetOpInfo,
                                        SymbolLookUp, DisInfo);
 }
 
-extern "C" void LLVMInitializeAArch64Disassembler() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeAArch64Disassembler() {
   TargetRegistry::RegisterMCDisassembler(getTheAArch64leTarget(),
                                          createAArch64Disassembler);
   TargetRegistry::RegisterMCDisassembler(getTheAArch64beTarget(),

lib/Target/AArch64/MCTargetDesc/AArch64MCTargetDesc.cpp

@@ -366,7 +366,7 @@ static MCInstrAnalysis *createAArch64InstrAnalysis(const MCInstrInfo *Info) {
 }
 
 // Force static initialization.
-extern "C" void LLVMInitializeAArch64TargetMC() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeAArch64TargetMC() {
   for (Target *T : {&getTheAArch64leTarget(), &getTheAArch64beTarget(),
                     &getTheAArch64_32Target(), &getTheARM64Target(),
                     &getTheARM64_32Target()}) {

lib/Target/AArch64/TargetInfo/AArch64TargetInfo.cpp

@@ -31,7 +31,7 @@ Target &llvm::getTheARM64_32Target() {
   return TheARM64_32Target;
 }
 
-extern "C" void LLVMInitializeAArch64TargetInfo() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeAArch64TargetInfo() {
   // Now register the "arm64" name for use with "-march". We don't want it to
   // take possession of the Triple::aarch64 tags though.
   TargetRegistry::RegisterTarget(getTheARM64Target(), "arm64",

lib/Target/AMDGPU/AMDGPUAsmPrinter.cpp

@@ -90,7 +90,7 @@ createAMDGPUAsmPrinterPass(TargetMachine &tm,
   return new AMDGPUAsmPrinter(tm, std::move(Streamer));
 }
 
-extern "C" void LLVMInitializeAMDGPUAsmPrinter() {
+extern "C" void LLVM_EXTERNAL_VISIBILITY LLVMInitializeAMDGPUAsmPrinter() {
   TargetRegistry::RegisterAsmPrinter(getTheAMDGPUTarget(),
                                      llvm::createR600AsmPrinterPass);
   TargetRegistry::RegisterAsmPrinter(getTheGCNTarget(),

lib/Target/AMDGPU/AMDGPUTargetMachine.cpp

@@ -183,7 +183,7 @@ static cl::opt<bool> EnableScalarIRPasses(
   cl::init(true),
   cl::Hidden);
 
-extern "C" void LLVMInitializeAMDGPUTarget() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeAMDGPUTarget() {
   // Register the target
   RegisterTargetMachine<R600TargetMachine> X(getTheAMDGPUTarget());
   RegisterTargetMachine<GCNTargetMachine> Y(getTheGCNTarget());

lib/Target/AMDGPU/AsmParser/AMDGPUAsmParser.cpp

@@ -6980,7 +6980,7 @@ AMDGPUOperand::Ptr AMDGPUAsmParser::defaultABID() const {
 }
 
 /// Force static initialization.
-extern "C" void LLVMInitializeAMDGPUAsmParser() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeAMDGPUAsmParser() {
   RegisterMCAsmParser<AMDGPUAsmParser> A(getTheAMDGPUTarget());
   RegisterMCAsmParser<AMDGPUAsmParser> B(getTheGCNTarget());
 }

lib/Target/AMDGPU/Disassembler/AMDGPUDisassembler.cpp

@@ -1252,7 +1252,7 @@ static MCDisassembler *createAMDGPUDisassembler(const Target &T,
   return new AMDGPUDisassembler(STI, Ctx, T.createMCInstrInfo());
 }
 
-extern "C" void LLVMInitializeAMDGPUDisassembler() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeAMDGPUDisassembler() {
   TargetRegistry::RegisterMCDisassembler(getTheGCNTarget(),
                                          createAMDGPUDisassembler);
   TargetRegistry::RegisterMCSymbolizer(getTheGCNTarget(),

lib/Target/AMDGPU/MCTargetDesc/AMDGPUMCTargetDesc.cpp

@@ -134,7 +134,7 @@ static MCInstrAnalysis *createAMDGPUMCInstrAnalysis(const MCInstrInfo *Info) {
   return new AMDGPUMCInstrAnalysis(Info);
 }
 
-extern "C" void LLVMInitializeAMDGPUTargetMC() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeAMDGPUTargetMC() {
 
   TargetRegistry::RegisterMCInstrInfo(getTheGCNTarget(), createAMDGPUMCInstrInfo);
   TargetRegistry::RegisterMCInstrInfo(getTheAMDGPUTarget(), createR600MCInstrInfo);

lib/Target/AMDGPU/TargetInfo/AMDGPUTargetInfo.cpp

@@ -28,7 +28,7 @@ Target &llvm::getTheGCNTarget() {
 }
 
 /// Extern function to initialize the targets for the AMDGPU backend
-extern "C" void LLVMInitializeAMDGPUTargetInfo() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeAMDGPUTargetInfo() {
   RegisterTarget<Triple::r600, false> R600(getTheAMDGPUTarget(), "r600",
                                            "AMD GPUs HD2XXX-HD6XXX", "AMDGPU");
   RegisterTarget<Triple::amdgcn, false> GCN(getTheGCNTarget(), "amdgcn",

lib/Target/ARC/ARCAsmPrinter.cpp

@@ -62,6 +62,6 @@ void ARCAsmPrinter::EmitInstruction(const MachineInstr *MI) {
 }
 
 // Force static initialization.
-extern "C" void LLVMInitializeARCAsmPrinter() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeARCAsmPrinter() {
   RegisterAsmPrinter<ARCAsmPrinter> X(getTheARCTarget());
 }

lib/Target/ARC/ARCTargetMachine.cpp

@@ -81,7 +81,7 @@ void ARCPassConfig::addPreRegAlloc() {
 }
 
 // Force static initialization.
-extern "C" void LLVMInitializeARCTarget() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeARCTarget() {
   RegisterTargetMachine<ARCTargetMachine> X(getTheARCTarget());
 }
 

lib/Target/ARC/Disassembler/ARCDisassembler.cpp

@@ -363,7 +363,7 @@ static MCDisassembler *createARCDisassembler(const Target &T,
   return new ARCDisassembler(STI, Ctx, T.createMCInstrInfo());
 }
 
-extern "C" void LLVMInitializeARCDisassembler() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeARCDisassembler() {
   // Register the disassembler.
   TargetRegistry::RegisterMCDisassembler(getTheARCTarget(),
                                          createARCDisassembler);

lib/Target/ARC/MCTargetDesc/ARCMCTargetDesc.cpp

@@ -82,7 +82,7 @@ static MCTargetStreamer *createTargetAsmStreamer(MCStreamer &S,
 }
 
 // Force static initialization.
-extern "C" void LLVMInitializeARCTargetMC() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeARCTargetMC() {
   // Register the MC asm info.
   Target &TheARCTarget = getTheARCTarget();
   RegisterMCAsmInfoFn X(TheARCTarget, createARCMCAsmInfo);

lib/Target/ARC/TargetInfo/ARCTargetInfo.cpp

@@ -16,6 +16,6 @@ Target &llvm::getTheARCTarget() {
   return TheARCTarget;
 }
 
-extern "C" void LLVMInitializeARCTargetInfo() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeARCTargetInfo() {
   RegisterTarget<Triple::arc> X(getTheARCTarget(), "arc", "ARC", "ARC");
 }

lib/Target/ARM/ARMAsmPrinter.cpp

@@ -2148,7 +2148,7 @@ void ARMAsmPrinter::EmitInstruction(const MachineInstr *MI) {
 //===----------------------------------------------------------------------===//
 
 // Force static initialization.
-extern "C" void LLVMInitializeARMAsmPrinter() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeARMAsmPrinter() {
   RegisterAsmPrinter<ARMAsmPrinter> X(getTheARMLETarget());
   RegisterAsmPrinter<ARMAsmPrinter> Y(getTheARMBETarget());
   RegisterAsmPrinter<ARMAsmPrinter> A(getTheThumbLETarget());

lib/Target/ARM/ARMTargetMachine.cpp

@@ -79,7 +79,7 @@ namespace llvm {
   void initializeARMExecutionDomainFixPass(PassRegistry&);
 }
 
-extern "C" void LLVMInitializeARMTarget() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeARMTarget() {
   // Register the target.
   RegisterTargetMachine<ARMLETargetMachine> X(getTheARMLETarget());
   RegisterTargetMachine<ARMLETargetMachine> A(getTheThumbLETarget());

lib/Target/ARM/AsmParser/ARMAsmParser.cpp

@@ -11546,7 +11546,7 @@ bool ARMAsmParser::parseDirectiveThumbSet(SMLoc L) {
 }
 
 /// Force static initialization.
-extern "C" void LLVMInitializeARMAsmParser() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeARMAsmParser() {
   RegisterMCAsmParser<ARMAsmParser> X(getTheARMLETarget());
   RegisterMCAsmParser<ARMAsmParser> Y(getTheARMBETarget());
   RegisterMCAsmParser<ARMAsmParser> A(getTheThumbLETarget());

lib/Target/ARM/Disassembler/ARMDisassembler.cpp

@@ -1099,7 +1099,7 @@ DecodeStatus ARMDisassembler::getThumbInstruction(MCInst &MI, uint64_t &Size,
   return MCDisassembler::Fail;
 }
 
-extern "C" void LLVMInitializeARMDisassembler() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeARMDisassembler() {
   TargetRegistry::RegisterMCDisassembler(getTheARMLETarget(),
                                          createARMDisassembler);
   TargetRegistry::RegisterMCDisassembler(getTheARMBETarget(),

lib/Target/ARM/MCTargetDesc/ARMMCTargetDesc.cpp

@@ -317,7 +317,7 @@ static MCInstrAnalysis *createThumbMCInstrAnalysis(const MCInstrInfo *Info) {
 }
 
 // Force static initialization.
-extern "C" void LLVMInitializeARMTargetMC() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeARMTargetMC() {
   for (Target *T : {&getTheARMLETarget(), &getTheARMBETarget(),
                     &getTheThumbLETarget(), &getTheThumbBETarget()}) {
     // Register the MC asm info.

lib/Target/ARM/TargetInfo/ARMTargetInfo.cpp

@@ -27,7 +27,7 @@ Target &llvm::getTheThumbBETarget() {
   return TheThumbBETarget;
 }
 
-extern "C" void LLVMInitializeARMTargetInfo() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeARMTargetInfo() {
   RegisterTarget<Triple::arm, /*HasJIT=*/true> X(getTheARMLETarget(), "arm",
                                                  "ARM", "ARM");
   RegisterTarget<Triple::armeb, /*HasJIT=*/true> Y(getTheARMBETarget(), "armeb",

lib/Target/AVR/AVRAsmPrinter.cpp

@@ -178,7 +178,7 @@ void AVRAsmPrinter::EmitInstruction(const MachineInstr *MI) {
 
 } // end of namespace llvm
 
-extern "C" void LLVMInitializeAVRAsmPrinter() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeAVRAsmPrinter() {
   llvm::RegisterAsmPrinter<llvm::AVRAsmPrinter> X(llvm::getTheAVRTarget());
 }
 

lib/Target/AVR/AVRTargetMachine.cpp

@@ -76,7 +76,7 @@ TargetPassConfig *AVRTargetMachine::createPassConfig(PassManagerBase &PM) {
   return new AVRPassConfig(*this, PM);
 }
 
-extern "C" void LLVMInitializeAVRTarget() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeAVRTarget() {
   // Register the target.
   RegisterTargetMachine<AVRTargetMachine> X(getTheAVRTarget());
 

lib/Target/AVR/AsmParser/AVRAsmParser.cpp

@@ -682,7 +682,7 @@ bool AVRAsmParser::parseLiteralValues(unsigned SizeInBytes, SMLoc L) {
   return (parseMany(parseOne));
 }
 
-extern "C" void LLVMInitializeAVRAsmParser() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeAVRAsmParser() {
   RegisterMCAsmParser<AVRAsmParser> X(getTheAVRTarget());
 }
 

lib/Target/AVR/Disassembler/AVRDisassembler.cpp

@@ -51,7 +51,7 @@ static MCDisassembler *createAVRDisassembler(const Target &T,
 }
 
 
-extern "C" void LLVMInitializeAVRDisassembler() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeAVRDisassembler() {
   // Register the disassembler.
   TargetRegistry::RegisterMCDisassembler(getTheAVRTarget(),
                                          createAVRDisassembler);

lib/Target/AVR/MCTargetDesc/AVRMCTargetDesc.cpp

@@ -89,7 +89,7 @@ static MCTargetStreamer *createMCAsmTargetStreamer(MCStreamer &S,
   return new AVRTargetAsmStreamer(S);
 }
 
-extern "C" void LLVMInitializeAVRTargetMC() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeAVRTargetMC() {
   // Register the MC asm info.
   RegisterMCAsmInfo<AVRMCAsmInfo> X(getTheAVRTarget());
 

lib/Target/AVR/TargetInfo/AVRTargetInfo.cpp

@@ -15,7 +15,7 @@ Target &getTheAVRTarget() {
 }
 }
 
-extern "C" void LLVMInitializeAVRTargetInfo() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeAVRTargetInfo() {
   llvm::RegisterTarget<llvm::Triple::avr> X(llvm::getTheAVRTarget(), "avr",
                                             "Atmel AVR Microcontroller", "AVR");
 }

lib/Target/BPF/AsmParser/BPFAsmParser.cpp

@@ -493,7 +493,7 @@ bool BPFAsmParser::ParseInstruction(ParseInstructionInfo &Info, StringRef Name,
 
 bool BPFAsmParser::ParseDirective(AsmToken DirectiveID) { return true; }
 
-extern "C" void LLVMInitializeBPFAsmParser() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeBPFAsmParser() {
   RegisterMCAsmParser<BPFAsmParser> X(getTheBPFTarget());
   RegisterMCAsmParser<BPFAsmParser> Y(getTheBPFleTarget());
   RegisterMCAsmParser<BPFAsmParser> Z(getTheBPFbeTarget());

lib/Target/BPF/BPFAsmPrinter.cpp

@@ -148,7 +148,7 @@ void BPFAsmPrinter::EmitInstruction(const MachineInstr *MI) {
 }
 
 // Force static initialization.
-extern "C" void LLVMInitializeBPFAsmPrinter() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeBPFAsmPrinter() {
   RegisterAsmPrinter<BPFAsmPrinter> X(getTheBPFleTarget());
   RegisterAsmPrinter<BPFAsmPrinter> Y(getTheBPFbeTarget());
   RegisterAsmPrinter<BPFAsmPrinter> Z(getTheBPFTarget());

lib/Target/BPF/BPFTargetMachine.cpp

@@ -27,7 +27,7 @@ static cl::
 opt<bool> DisableMIPeephole("disable-bpf-peephole", cl::Hidden,
                             cl::desc("Disable machine peepholes for BPF"));
 
-extern "C" void LLVMInitializeBPFTarget() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeBPFTarget() {
   // Register the target.
   RegisterTargetMachine<BPFTargetMachine> X(getTheBPFleTarget());
   RegisterTargetMachine<BPFTargetMachine> Y(getTheBPFbeTarget());

lib/Target/BPF/Disassembler/BPFDisassembler.cpp

@@ -83,7 +83,7 @@ static MCDisassembler *createBPFDisassembler(const Target &T,
 }
 
 
-extern "C" void LLVMInitializeBPFDisassembler() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeBPFDisassembler() {
   // Register the disassembler.
   TargetRegistry::RegisterMCDisassembler(getTheBPFTarget(),
                                          createBPFDisassembler);

lib/Target/BPF/MCTargetDesc/BPFMCTargetDesc.cpp

@@ -97,7 +97,7 @@ static MCInstrAnalysis *createBPFInstrAnalysis(const MCInstrInfo *Info) {
   return new BPFMCInstrAnalysis(Info);
 }
 
-extern "C" void LLVMInitializeBPFTargetMC() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeBPFTargetMC() {
   for (Target *T :
        {&getTheBPFleTarget(), &getTheBPFbeTarget(), &getTheBPFTarget()}) {
     // Register the MC asm info.

lib/Target/BPF/TargetInfo/BPFTargetInfo.cpp

@@ -24,7 +24,7 @@ Target &llvm::getTheBPFTarget() {
   return TheBPFTarget;
 }
 
-extern "C" void LLVMInitializeBPFTargetInfo() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeBPFTargetInfo() {
   TargetRegistry::RegisterTarget(getTheBPFTarget(), "bpf", "BPF (host endian)",
                                  "BPF", [](Triple::ArchType) { return false; },
                                  true);

lib/Target/CMakeLists.txt

@@ -13,6 +13,14 @@ add_llvm_component_library(LLVMTarget
   ${LLVM_MAIN_INCLUDE_DIR}/llvm/Target
   )
 
+# When building shared objects for each target there are some internal APIs
+# that are used across shared objects which we can't hide.
+if (NOT BUILD_SHARED_LIBS AND NOT APPLE)
+  # Set default visibility to hidden, so we don't export all the Target classes
+  # in libLLVM.so.
+  set(CMAKE_CXX_VISIBILITY_PRESET hidden)
+endif()
+
 foreach(t ${LLVM_TARGETS_TO_BUILD})
   message(STATUS "Targeting ${t}")
   add_subdirectory(${t})

lib/Target/Hexagon/AsmParser/HexagonAsmParser.cpp

@@ -813,10 +813,10 @@ bool HexagonAsmParser::RegisterMatchesArch(unsigned MatchNum) const {
   return true;
 }
 
-// extern "C" void LLVMInitializeHexagonAsmLexer();
+// extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeHexagonAsmLexer();
 
 /// Force static initialization.
-extern "C" void LLVMInitializeHexagonAsmParser() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeHexagonAsmParser() {
   RegisterMCAsmParser<HexagonAsmParser> X(getTheHexagonTarget());
 }
 

lib/Target/Hexagon/Disassembler/HexagonDisassembler.cpp

@@ -156,7 +156,7 @@ static MCDisassembler *createHexagonDisassembler(const Target &T,
   return new HexagonDisassembler(STI, Ctx, T.createMCInstrInfo());
 }
 
-extern "C" void LLVMInitializeHexagonDisassembler() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeHexagonDisassembler() {
   TargetRegistry::RegisterMCDisassembler(getTheHexagonTarget(),
                                          createHexagonDisassembler);
 }

lib/Target/Hexagon/HexagonAsmPrinter.cpp

@@ -771,6 +771,6 @@ void HexagonAsmPrinter::EmitInstruction(const MachineInstr *MI) {
   OutStreamer->EmitInstruction(MCB, getSubtargetInfo());
 }
 
-extern "C" void LLVMInitializeHexagonAsmPrinter() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeHexagonAsmPrinter() {
   RegisterAsmPrinter<HexagonAsmPrinter> X(getTheHexagonTarget());
 }

lib/Target/Hexagon/HexagonTargetMachine.cpp

@@ -180,7 +180,7 @@ static Reloc::Model getEffectiveRelocModel(Optional<Reloc::Model> RM) {
   return *RM;
 }
 
-extern "C" void LLVMInitializeHexagonTarget() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeHexagonTarget() {
   // Register the target.
   RegisterTargetMachine<HexagonTargetMachine> X(getTheHexagonTarget());
 

lib/Target/Hexagon/MCTargetDesc/HexagonMCTargetDesc.cpp

@@ -456,7 +456,7 @@ static MCInstrAnalysis *createHexagonMCInstrAnalysis(const MCInstrInfo *Info) {
 }
 
 // Force static initialization.
-extern "C" void LLVMInitializeHexagonTargetMC() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeHexagonTargetMC() {
   // Register the MC asm info.
   RegisterMCAsmInfoFn X(getTheHexagonTarget(), createHexagonMCAsmInfo);
 

lib/Target/Hexagon/TargetInfo/HexagonTargetInfo.cpp

@@ -15,7 +15,7 @@ Target &llvm::getTheHexagonTarget() {
   return TheHexagonTarget;
 }
 
-extern "C" void LLVMInitializeHexagonTargetInfo() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeHexagonTargetInfo() {
   RegisterTarget<Triple::hexagon, /*HasJIT=*/true> X(
       getTheHexagonTarget(), "hexagon", "Hexagon", "Hexagon");
 }

lib/Target/Lanai/AsmParser/LanaiAsmParser.cpp

@@ -1224,6 +1224,6 @@ bool LanaiAsmParser::ParseInstruction(ParseInstructionInfo & /*Info*/,
 #define GET_MATCHER_IMPLEMENTATION
 #include "LanaiGenAsmMatcher.inc"
 
-extern "C" void LLVMInitializeLanaiAsmParser() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeLanaiAsmParser() {
   RegisterMCAsmParser<LanaiAsmParser> x(getTheLanaiTarget());
 }

lib/Target/Lanai/Disassembler/LanaiDisassembler.cpp

@@ -36,7 +36,7 @@ static MCDisassembler *createLanaiDisassembler(const Target & /*T*/,
   return new LanaiDisassembler(STI, Ctx);
 }
 
-extern "C" void LLVMInitializeLanaiDisassembler() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeLanaiDisassembler() {
   // Register the disassembler
   TargetRegistry::RegisterMCDisassembler(getTheLanaiTarget(),
                                          createLanaiDisassembler);

lib/Target/Lanai/LanaiAsmPrinter.cpp

@@ -237,6 +237,6 @@ bool LanaiAsmPrinter::isBlockOnlyReachableByFallthrough(
 }
 
 // Force static initialization.
-extern "C" void LLVMInitializeLanaiAsmPrinter() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeLanaiAsmPrinter() {
   RegisterAsmPrinter<LanaiAsmPrinter> X(getTheLanaiTarget());
 }

lib/Target/Lanai/LanaiTargetMachine.cpp

@@ -30,7 +30,7 @@ namespace llvm {
 void initializeLanaiMemAluCombinerPass(PassRegistry &);
 } // namespace llvm
 
-extern "C" void LLVMInitializeLanaiTarget() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeLanaiTarget() {
   // Register the target.
   RegisterTargetMachine<LanaiTargetMachine> registered_target(
       getTheLanaiTarget());

lib/Target/Lanai/MCTargetDesc/LanaiMCTargetDesc.cpp

@@ -123,7 +123,7 @@ static MCInstrAnalysis *createLanaiInstrAnalysis(const MCInstrInfo *Info) {
   return new LanaiMCInstrAnalysis(Info);
 }
 
-extern "C" void LLVMInitializeLanaiTargetMC() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeLanaiTargetMC() {
   // Register the MC asm info.
   RegisterMCAsmInfo<LanaiMCAsmInfo> X(getTheLanaiTarget());
 

lib/Target/Lanai/TargetInfo/LanaiTargetInfo.cpp

@@ -16,7 +16,7 @@ Target &llvm::getTheLanaiTarget() {
   return TheLanaiTarget;
 }
 
-extern "C" void LLVMInitializeLanaiTargetInfo() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeLanaiTargetInfo() {
   RegisterTarget<Triple::lanai> X(getTheLanaiTarget(), "lanai", "Lanai",
                                   "Lanai");
 }

lib/Target/MSP430/AsmParser/MSP430AsmParser.cpp

@@ -529,7 +529,7 @@ bool MSP430AsmParser::ParseLiteralValues(unsigned Size, SMLoc L) {
   return (parseMany(parseOne));
 }
 
-extern "C" void LLVMInitializeMSP430AsmParser() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeMSP430AsmParser() {
   RegisterMCAsmParser<MSP430AsmParser> X(getTheMSP430Target());
 }
 

lib/Target/MSP430/Disassembler/MSP430Disassembler.cpp

@@ -58,7 +58,7 @@ static MCDisassembler *createMSP430Disassembler(const Target &T,
   return new MSP430Disassembler(STI, Ctx);
 }
 
-extern "C" void LLVMInitializeMSP430Disassembler() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeMSP430Disassembler() {
   TargetRegistry::RegisterMCDisassembler(getTheMSP430Target(),
                                          createMSP430Disassembler);
 }

lib/Target/MSP430/MCTargetDesc/MSP430MCTargetDesc.cpp

@@ -57,7 +57,7 @@ static MCInstPrinter *createMSP430MCInstPrinter(const Triple &T,
   return nullptr;
 }
 
-extern "C" void LLVMInitializeMSP430TargetMC() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeMSP430TargetMC() {
   Target &T = getTheMSP430Target();
 
   RegisterMCAsmInfo<MSP430MCAsmInfo> X(T);

lib/Target/MSP430/MSP430AsmPrinter.cpp

@@ -185,6 +185,6 @@ bool MSP430AsmPrinter::runOnMachineFunction(MachineFunction &MF) {
 }
 
 // Force static initialization.
-extern "C" void LLVMInitializeMSP430AsmPrinter() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeMSP430AsmPrinter() {
   RegisterAsmPrinter<MSP430AsmPrinter> X(getTheMSP430Target());
 }

lib/Target/MSP430/MSP430TargetMachine.cpp

@@ -21,7 +21,7 @@
 #include "llvm/Support/TargetRegistry.h"
 using namespace llvm;
 
-extern "C" void LLVMInitializeMSP430Target() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeMSP430Target() {
   // Register the target.
   RegisterTargetMachine<MSP430TargetMachine> X(getTheMSP430Target());
 }

lib/Target/MSP430/TargetInfo/MSP430TargetInfo.cpp

@@ -15,7 +15,7 @@ Target &llvm::getTheMSP430Target() {
   return TheMSP430Target;
 }
 
-extern "C" void LLVMInitializeMSP430TargetInfo() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeMSP430TargetInfo() {
   RegisterTarget<Triple::msp430> X(getTheMSP430Target(), "msp430",
                                    "MSP430 [experimental]", "MSP430");
 }

lib/Target/Mips/AsmParser/MipsAsmParser.cpp

@@ -8645,7 +8645,7 @@ bool MipsAsmParser::parseInternalDirectiveReallowModule() {
   return false;
 }
 
-extern "C" void LLVMInitializeMipsAsmParser() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeMipsAsmParser() {
   RegisterMCAsmParser<MipsAsmParser> X(getTheMipsTarget());
   RegisterMCAsmParser<MipsAsmParser> Y(getTheMipselTarget());
   RegisterMCAsmParser<MipsAsmParser> A(getTheMips64Target());

lib/Target/Mips/Disassembler/MipsDisassembler.cpp

@@ -563,7 +563,7 @@ static MCDisassembler *createMipselDisassembler(
   return new MipsDisassembler(STI, Ctx, false);
 }
 
-extern "C" void LLVMInitializeMipsDisassembler() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeMipsDisassembler() {
   // Register the disassembler.
   TargetRegistry::RegisterMCDisassembler(getTheMipsTarget(),
                                          createMipsDisassembler);

lib/Target/Mips/MCTargetDesc/MipsMCTargetDesc.cpp

@@ -166,7 +166,7 @@ static MCInstrAnalysis *createMipsMCInstrAnalysis(const MCInstrInfo *Info) {
   return new MipsMCInstrAnalysis(Info);
 }
 
-extern "C" void LLVMInitializeMipsTargetMC() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeMipsTargetMC() {
   for (Target *T : {&getTheMipsTarget(), &getTheMipselTarget(),
                     &getTheMips64Target(), &getTheMips64elTarget()}) {
     // Register the MC asm info.

lib/Target/Mips/MipsAsmPrinter.cpp

@@ -1306,7 +1306,7 @@ bool MipsAsmPrinter::isLongBranchPseudo(int Opcode) const {
 }
 
 // Force static initialization.
-extern "C" void LLVMInitializeMipsAsmPrinter() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeMipsAsmPrinter() {
   RegisterAsmPrinter<MipsAsmPrinter> X(getTheMipsTarget());
   RegisterAsmPrinter<MipsAsmPrinter> Y(getTheMipselTarget());
   RegisterAsmPrinter<MipsAsmPrinter> A(getTheMips64Target());

lib/Target/Mips/MipsTargetMachine.cpp

@@ -45,7 +45,7 @@ using namespace llvm;
 
 #define DEBUG_TYPE "mips"
 
-extern "C" void LLVMInitializeMipsTarget() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeMipsTarget() {
   // Register the target.
   RegisterTargetMachine<MipsebTargetMachine> X(getTheMipsTarget());
   RegisterTargetMachine<MipselTargetMachine> Y(getTheMipselTarget());

lib/Target/Mips/TargetInfo/MipsTargetInfo.cpp

@@ -27,7 +27,7 @@ Target &llvm::getTheMips64elTarget() {
   return TheMips64elTarget;
 }
 
-extern "C" void LLVMInitializeMipsTargetInfo() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeMipsTargetInfo() {
   RegisterTarget<Triple::mips,
                  /*HasJIT=*/true>
       X(getTheMipsTarget(), "mips", "MIPS (32-bit big endian)", "Mips");

lib/Target/NVPTX/MCTargetDesc/NVPTXMCTargetDesc.cpp

@@ -66,7 +66,7 @@ static MCTargetStreamer *createTargetAsmStreamer(MCStreamer &S,
 }
 
 // Force static initialization.
-extern "C" void LLVMInitializeNVPTXTargetMC() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeNVPTXTargetMC() {
   for (Target *T : {&getTheNVPTXTarget32(), &getTheNVPTXTarget64()}) {
     // Register the MC asm info.
     RegisterMCAsmInfo<NVPTXMCAsmInfo> X(*T);

lib/Target/NVPTX/NVPTXAsmPrinter.cpp

@@ -2258,7 +2258,7 @@ void NVPTXAsmPrinter::printMemOperand(const MachineInstr *MI, int opNum,
 }
 
 // Force static initialization.
-extern "C" void LLVMInitializeNVPTXAsmPrinter() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeNVPTXAsmPrinter() {
   RegisterAsmPrinter<NVPTXAsmPrinter> X(getTheNVPTXTarget32());
   RegisterAsmPrinter<NVPTXAsmPrinter> Y(getTheNVPTXTarget64());
 }

lib/Target/NVPTX/NVPTXTargetMachine.cpp

@@ -72,7 +72,7 @@ void initializeNVPTXProxyRegErasurePass(PassRegistry &);
 
 } // end namespace llvm
 
-extern "C" void LLVMInitializeNVPTXTarget() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeNVPTXTarget() {
   // Register the target.
   RegisterTargetMachine<NVPTXTargetMachine32> X(getTheNVPTXTarget32());
   RegisterTargetMachine<NVPTXTargetMachine64> Y(getTheNVPTXTarget64());

lib/Target/NVPTX/TargetInfo/NVPTXTargetInfo.cpp

@@ -19,7 +19,7 @@ Target &llvm::getTheNVPTXTarget64() {
   return TheNVPTXTarget64;
 }
 
-extern "C" void LLVMInitializeNVPTXTargetInfo() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeNVPTXTargetInfo() {
   RegisterTarget<Triple::nvptx> X(getTheNVPTXTarget32(), "nvptx",
                                   "NVIDIA PTX 32-bit", "NVPTX");
   RegisterTarget<Triple::nvptx64> Y(getTheNVPTXTarget64(), "nvptx64",

lib/Target/PowerPC/AsmParser/PPCAsmParser.cpp

@@ -1786,7 +1786,7 @@ bool PPCAsmParser::ParseDirectiveLocalEntry(SMLoc L) {
 
 
 /// Force static initialization.
-extern "C" void LLVMInitializePowerPCAsmParser() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializePowerPCAsmParser() {
   RegisterMCAsmParser<PPCAsmParser> A(getThePPC32Target());
   RegisterMCAsmParser<PPCAsmParser> B(getThePPC64Target());
   RegisterMCAsmParser<PPCAsmParser> C(getThePPC64LETarget());

lib/Target/PowerPC/Disassembler/PPCDisassembler.cpp

@@ -50,7 +50,7 @@ static MCDisassembler *createPPCLEDisassembler(const Target &T,
   return new PPCDisassembler(STI, Ctx, /*IsLittleEndian=*/true);
 }
 
-extern "C" void LLVMInitializePowerPCDisassembler() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializePowerPCDisassembler() {
   // Register the disassembler for each target.
   TargetRegistry::RegisterMCDisassembler(getThePPC32Target(),
                                          createPPCDisassembler);

lib/Target/PowerPC/MCTargetDesc/PPCMCTargetDesc.cpp

@@ -292,7 +292,7 @@ static MCInstPrinter *createPPCMCInstPrinter(const Triple &T,
   return new PPCInstPrinter(MAI, MII, MRI, T);
 }
 
-extern "C" void LLVMInitializePowerPCTargetMC() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializePowerPCTargetMC() {
   for (Target *T :
        {&getThePPC32Target(), &getThePPC64Target(), &getThePPC64LETarget()}) {
     // Register the MC asm info.

lib/Target/PowerPC/PPCAsmPrinter.cpp

@@ -1801,7 +1801,7 @@ createPPCAsmPrinterPass(TargetMachine &tm,
 }
 
 // Force static initialization.
-extern "C" void LLVMInitializePowerPCAsmPrinter() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializePowerPCAsmPrinter() {
   TargetRegistry::RegisterAsmPrinter(getThePPC32Target(),
                                      createPPCAsmPrinterPass);
   TargetRegistry::RegisterAsmPrinter(getThePPC64Target(),

lib/Target/PowerPC/PPCTargetMachine.cpp

@@ -94,7 +94,7 @@ static cl::opt<bool>
   ReduceCRLogical("ppc-reduce-cr-logicals",
                   cl::desc("Expand eligible cr-logical binary ops to branches"),
                   cl::init(true), cl::Hidden);
-extern "C" void LLVMInitializePowerPCTarget() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializePowerPCTarget() {
   // Register the targets
   RegisterTargetMachine<PPCTargetMachine> A(getThePPC32Target());
   RegisterTargetMachine<PPCTargetMachine> B(getThePPC64Target());

lib/Target/PowerPC/TargetInfo/PowerPCTargetInfo.cpp

@@ -23,7 +23,7 @@ Target &llvm::getThePPC64LETarget() {
   return ThePPC64LETarget;
 }
 
-extern "C" void LLVMInitializePowerPCTargetInfo() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializePowerPCTargetInfo() {
   RegisterTarget<Triple::ppc, /*HasJIT=*/true> X(getThePPC32Target(), "ppc32",
                                                  "PowerPC 32", "PPC");
 

lib/Target/RISCV/AsmParser/RISCVAsmParser.cpp

@@ -1872,7 +1872,7 @@ bool RISCVAsmParser::processInstruction(MCInst &Inst, SMLoc IDLoc,
   return false;
 }
 
-extern "C" void LLVMInitializeRISCVAsmParser() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeRISCVAsmParser() {
   RegisterMCAsmParser<RISCVAsmParser> X(getTheRISCV32Target());
   RegisterMCAsmParser<RISCVAsmParser> Y(getTheRISCV64Target());
 }

lib/Target/RISCV/Disassembler/RISCVDisassembler.cpp

@@ -48,7 +48,7 @@ static MCDisassembler *createRISCVDisassembler(const Target &T,
   return new RISCVDisassembler(STI, Ctx);
 }
 
-extern "C" void LLVMInitializeRISCVDisassembler() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeRISCVDisassembler() {
   // Register the disassembler for each target.
   TargetRegistry::RegisterMCDisassembler(getTheRISCV32Target(),
                                          createRISCVDisassembler);

lib/Target/RISCV/MCTargetDesc/RISCVMCTargetDesc.cpp

@@ -93,7 +93,7 @@ static MCTargetStreamer *createRISCVAsmTargetStreamer(MCStreamer &S,
   return new RISCVTargetAsmStreamer(S, OS);
 }
 
-extern "C" void LLVMInitializeRISCVTargetMC() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeRISCVTargetMC() {
   for (Target *T : {&getTheRISCV32Target(), &getTheRISCV64Target()}) {
     TargetRegistry::RegisterMCAsmInfo(*T, createRISCVMCAsmInfo);
     TargetRegistry::RegisterMCInstrInfo(*T, createRISCVMCInstrInfo);

lib/Target/RISCV/RISCVAsmPrinter.cpp

@@ -155,7 +155,7 @@ bool RISCVAsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI,
 }
 
 // Force static initialization.
-extern "C" void LLVMInitializeRISCVAsmPrinter() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeRISCVAsmPrinter() {
   RegisterAsmPrinter<RISCVAsmPrinter> X(getTheRISCV32Target());
   RegisterAsmPrinter<RISCVAsmPrinter> Y(getTheRISCV64Target());
 }

lib/Target/RISCV/RISCVTargetMachine.cpp

@@ -31,7 +31,7 @@
 #include "llvm/Target/TargetOptions.h"
 using namespace llvm;
 
-extern "C" void LLVMInitializeRISCVTarget() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeRISCVTarget() {
   RegisterTargetMachine<RISCVTargetMachine> X(getTheRISCV32Target());
   RegisterTargetMachine<RISCVTargetMachine> Y(getTheRISCV64Target());
   auto PR = PassRegistry::getPassRegistry();

lib/Target/RISCV/TargetInfo/RISCVTargetInfo.cpp

@@ -20,7 +20,7 @@ Target &llvm::getTheRISCV64Target() {
   return TheRISCV64Target;
 }
 
-extern "C" void LLVMInitializeRISCVTargetInfo() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeRISCVTargetInfo() {
   RegisterTarget<Triple::riscv32> X(getTheRISCV32Target(), "riscv32",
                                     "32-bit RISC-V", "RISCV");
   RegisterTarget<Triple::riscv64> Y(getTheRISCV64Target(), "riscv64",

lib/Target/Sparc/AsmParser/SparcAsmParser.cpp

@@ -1308,7 +1308,7 @@ bool SparcAsmParser::matchSparcAsmModifiers(const MCExpr *&EVal,
   return true;
 }
 
-extern "C" void LLVMInitializeSparcAsmParser() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeSparcAsmParser() {
   RegisterMCAsmParser<SparcAsmParser> A(getTheSparcTarget());
   RegisterMCAsmParser<SparcAsmParser> B(getTheSparcV9Target());
   RegisterMCAsmParser<SparcAsmParser> C(getTheSparcelTarget());

lib/Target/Sparc/Disassembler/SparcDisassembler.cpp

@@ -47,7 +47,7 @@ static MCDisassembler *createSparcDisassembler(const Target &T,
 }
 
 
-extern "C" void LLVMInitializeSparcDisassembler() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeSparcDisassembler() {
   // Register the disassembler.
   TargetRegistry::RegisterMCDisassembler(getTheSparcTarget(),
                                          createSparcDisassembler);

lib/Target/Sparc/MCTargetDesc/SparcMCTargetDesc.cpp

@@ -91,7 +91,7 @@ static MCInstPrinter *createSparcMCInstPrinter(const Triple &T,
   return new SparcInstPrinter(MAI, MII, MRI);
 }
 
-extern "C" void LLVMInitializeSparcTargetMC() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeSparcTargetMC() {
   // Register the MC asm info.
   RegisterMCAsmInfoFn X(getTheSparcTarget(), createSparcMCAsmInfo);
   RegisterMCAsmInfoFn Y(getTheSparcV9Target(), createSparcV9MCAsmInfo);

lib/Target/Sparc/SparcAsmPrinter.cpp

@@ -439,7 +439,7 @@ bool SparcAsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI,
 }
 
 // Force static initialization.
-extern "C" void LLVMInitializeSparcAsmPrinter() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeSparcAsmPrinter() {
   RegisterAsmPrinter<SparcAsmPrinter> X(getTheSparcTarget());
   RegisterAsmPrinter<SparcAsmPrinter> Y(getTheSparcV9Target());
   RegisterAsmPrinter<SparcAsmPrinter> Z(getTheSparcelTarget());

lib/Target/Sparc/SparcTargetMachine.cpp

@@ -20,7 +20,7 @@
 #include "llvm/Support/TargetRegistry.h"
 using namespace llvm;
 
-extern "C" void LLVMInitializeSparcTarget() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeSparcTarget() {
   // Register the target.
   RegisterTargetMachine<SparcV8TargetMachine> X(getTheSparcTarget());
   RegisterTargetMachine<SparcV9TargetMachine> Y(getTheSparcV9Target());

lib/Target/Sparc/TargetInfo/SparcTargetInfo.cpp

@@ -23,7 +23,7 @@ Target &llvm::getTheSparcelTarget() {
   return TheSparcelTarget;
 }
 
-extern "C" void LLVMInitializeSparcTargetInfo() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeSparcTargetInfo() {
   RegisterTarget<Triple::sparc, /*HasJIT=*/true> X(getTheSparcTarget(), "sparc",
                                                    "Sparc", "Sparc");
   RegisterTarget<Triple::sparcv9, /*HasJIT=*/true> Y(

lib/Target/SystemZ/AsmParser/SystemZAsmParser.cpp

@@ -1389,6 +1389,6 @@ SystemZAsmParser::parsePCRel(OperandVector &Operands, int64_t MinVal,
 }
 
 // Force static initialization.
-extern "C" void LLVMInitializeSystemZAsmParser() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeSystemZAsmParser() {
   RegisterMCAsmParser<SystemZAsmParser> X(getTheSystemZTarget());
 }

lib/Target/SystemZ/Disassembler/SystemZDisassembler.cpp

@@ -45,7 +45,7 @@ static MCDisassembler *createSystemZDisassembler(const Target &T,
   return new SystemZDisassembler(STI, Ctx);
 }
 
-extern "C" void LLVMInitializeSystemZDisassembler() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeSystemZDisassembler() {
   // Register the disassembler.
   TargetRegistry::RegisterMCDisassembler(getTheSystemZTarget(),
                                          createSystemZDisassembler);

lib/Target/SystemZ/MCTargetDesc/SystemZMCTargetDesc.cpp

@@ -183,7 +183,7 @@ static MCInstPrinter *createSystemZMCInstPrinter(const Triple &T,
   return new SystemZInstPrinter(MAI, MII, MRI);
 }
 
-extern "C" void LLVMInitializeSystemZTargetMC() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeSystemZTargetMC() {
   // Register the MCAsmInfo.
   TargetRegistry::RegisterMCAsmInfo(getTheSystemZTarget(),
                                     createSystemZMCAsmInfo);

lib/Target/SystemZ/SystemZAsmPrinter.cpp

@@ -724,6 +724,6 @@ void SystemZAsmPrinter::EmitEndOfAsmFile(Module &M) {
 }
 
 // Force static initialization.
-extern "C" void LLVMInitializeSystemZAsmPrinter() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeSystemZAsmPrinter() {
   RegisterAsmPrinter<SystemZAsmPrinter> X(getTheSystemZTarget());
 }

lib/Target/SystemZ/SystemZTargetMachine.cpp

@@ -29,7 +29,7 @@
 
 using namespace llvm;
 
-extern "C" void LLVMInitializeSystemZTarget() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeSystemZTarget() {
   // Register the target.
   RegisterTargetMachine<SystemZTargetMachine> X(getTheSystemZTarget());
 }

lib/Target/SystemZ/TargetInfo/SystemZTargetInfo.cpp

@@ -16,7 +16,7 @@ Target &llvm::getTheSystemZTarget() {
   return TheSystemZTarget;
 }
 
-extern "C" void LLVMInitializeSystemZTargetInfo() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeSystemZTargetInfo() {
   RegisterTarget<Triple::systemz, /*HasJIT=*/true> X(
       getTheSystemZTarget(), "systemz", "SystemZ", "SystemZ");
 }

lib/Target/WebAssembly/AsmParser/WebAssemblyAsmParser.cpp

@@ -899,7 +899,7 @@ public:
 } // end anonymous namespace
 
 // Force static initialization.
-extern "C" void LLVMInitializeWebAssemblyAsmParser() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeWebAssemblyAsmParser() {
   RegisterMCAsmParser<WebAssemblyAsmParser> X(getTheWebAssemblyTarget32());
   RegisterMCAsmParser<WebAssemblyAsmParser> Y(getTheWebAssemblyTarget64());
 }

lib/Target/WebAssembly/Disassembler/WebAssemblyDisassembler.cpp

@@ -64,7 +64,8 @@ static MCDisassembler *createWebAssemblyDisassembler(const Target &T,
   return new WebAssemblyDisassembler(STI, Ctx, std::move(MCII));
 }
 
-extern "C" void LLVMInitializeWebAssemblyDisassembler() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void
+LLVMInitializeWebAssemblyDisassembler() {
   // Register the disassembler for each target.
   TargetRegistry::RegisterMCDisassembler(getTheWebAssemblyTarget32(),
                                          createWebAssemblyDisassembler);

lib/Target/WebAssembly/MCTargetDesc/WebAssemblyMCTargetDesc.cpp

@@ -96,7 +96,7 @@ static MCTargetStreamer *createNullTargetStreamer(MCStreamer &S) {
 }
 
 // Force static initialization.
-extern "C" void LLVMInitializeWebAssemblyTargetMC() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeWebAssemblyTargetMC() {
   for (Target *T :
        {&getTheWebAssemblyTarget32(), &getTheWebAssemblyTarget64()}) {
     // Register the MC asm info.

lib/Target/WebAssembly/TargetInfo/WebAssemblyTargetInfo.cpp

@@ -26,7 +26,7 @@ Target &llvm::getTheWebAssemblyTarget64() {
   return TheWebAssemblyTarget64;
 }
 
-extern "C" void LLVMInitializeWebAssemblyTargetInfo() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeWebAssemblyTargetInfo() {
   RegisterTarget<Triple::wasm32> X(getTheWebAssemblyTarget32(), "wasm32",
                                    "WebAssembly 32-bit", "WebAssembly");
   RegisterTarget<Triple::wasm64> Y(getTheWebAssemblyTarget64(), "wasm64",

lib/Target/WebAssembly/WebAssemblyAsmPrinter.cpp

@@ -425,7 +425,7 @@ bool WebAssemblyAsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI,
 }
 
 // Force static initialization.
-extern "C" void LLVMInitializeWebAssemblyAsmPrinter() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeWebAssemblyAsmPrinter() {
   RegisterAsmPrinter<WebAssemblyAsmPrinter> X(getTheWebAssemblyTarget32());
   RegisterAsmPrinter<WebAssemblyAsmPrinter> Y(getTheWebAssemblyTarget64());
 }

lib/Target/WebAssembly/WebAssemblyTargetMachine.cpp

@@ -45,7 +45,7 @@ static cl::opt<bool> EnableEmSjLj(
     cl::desc("WebAssembly Emscripten-style setjmp/longjmp handling"),
     cl::init(false));
 
-extern "C" void LLVMInitializeWebAssemblyTarget() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeWebAssemblyTarget() {
   // Register the target.
   RegisterTargetMachine<WebAssemblyTargetMachine> X(
       getTheWebAssemblyTarget32());

lib/Target/X86/AsmParser/X86AsmParser.cpp

@@ -3939,7 +3939,7 @@ bool X86AsmParser::parseDirectiveSEHPushFrame(SMLoc Loc) {
 }
 
 // Force static initialization.
-extern "C" void LLVMInitializeX86AsmParser() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeX86AsmParser() {
   RegisterMCAsmParser<X86AsmParser> X(getTheX86_32Target());
   RegisterMCAsmParser<X86AsmParser> Y(getTheX86_64Target());
 }

lib/Target/X86/Disassembler/X86Disassembler.cpp

@@ -2332,7 +2332,7 @@ static MCDisassembler *createX86Disassembler(const Target &T,
   return new X86GenericDisassembler(STI, Ctx, std::move(MII));
 }
 
-extern "C" void LLVMInitializeX86Disassembler() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeX86Disassembler() {
   // Register the disassembler.
   TargetRegistry::RegisterMCDisassembler(getTheX86_32Target(),
                                          createX86Disassembler);

lib/Target/X86/MCTargetDesc/X86MCTargetDesc.cpp

@@ -552,7 +552,7 @@ static MCInstrAnalysis *createX86MCInstrAnalysis(const MCInstrInfo *Info) {
 }
 
 // Force static initialization.
-extern "C" void LLVMInitializeX86TargetMC() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeX86TargetMC() {
   for (Target *T : {&getTheX86_32Target(), &getTheX86_64Target()}) {
     // Register the MC asm info.
     RegisterMCAsmInfoFn X(*T, createX86MCAsmInfo);

lib/Target/X86/TargetInfo/X86TargetInfo.cpp

@@ -19,7 +19,7 @@ Target &llvm::getTheX86_64Target() {
   return TheX86_64Target;
 }
 
-extern "C" void LLVMInitializeX86TargetInfo() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeX86TargetInfo() {
   RegisterTarget<Triple::x86, /*HasJIT=*/true> X(
       getTheX86_32Target(), "x86", "32-bit X86: Pentium-Pro and above", "X86");
 

lib/Target/X86/X86AsmPrinter.cpp

@@ -749,7 +749,7 @@ void X86AsmPrinter::EmitEndOfAsmFile(Module &M) {
 //===----------------------------------------------------------------------===//
 
 // Force static initialization.
-extern "C" void LLVMInitializeX86AsmPrinter() {
+extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeX86AsmPrinter() {
   RegisterAsmPrinter<X86AsmPrinter> X(getTheX86_32Target());
   RegisterAsmPrinter<X86AsmPrinter> Y(getTheX86_64Target());
 }