Rafael Espindola 1f21e0dd0d Remove the linker_private and linker_private_weak linkages. ... These linkages were introduced some time ago, but it was never very clear what exactly their semantics were or what they should be used for. Some investigation found these uses: * utf-16 strings in clang. * non-unnamed_addr strings produced by the sanitizers. It turns out they were just working around a more fundamental problem. For some sections a MachO linker needs a symbol in order to split the section into atoms, and llvm had no idea that was the case. I fixed that in r201700 and it is now safe to use the private linkage. When the object ends up in a section that requires symbols, llvm will use a 'l' prefix instead of a 'L' prefix and things just work. With that, these linkages were already dead, but there was a potential future user in the objc metadata information. I am still looking at CGObjcMac.cpp, but at this point I am convinced that linker_private and linker_private_weak are not what they need. The objc uses are currently split in * Regular symbols (no '\01' prefix). LLVM already directly provides whatever semantics they need. * Uses of a private name (start with "\01L" or "\01l") and private linkage. We can drop the "\01L" and "\01l" prefixes as soon as llvm agrees with clang on L being ok or not for a given section. I have two patches in code review for this. * Uses of private name and weak linkage. The last case is the one that one could think would fit one of these linkages. That is not the case. The semantics are * the linker will merge these symbol by *name*. * the linker will hide them in the final DSO. Given that the merging is done by name, any of the private (or internal) linkages would be a bad match. They allow llvm to rename the symbols, and that is really not what we want. From the llvm point of view, these objects should really be (linkonce|weak)(_odr)?. For now, just keeping the "\01l" prefix is probably the best for these symbols. If we one day want to have a more direct support in llvm, IMHO what we should add is not a linkage, it is just a hidden_symbol attribute. It would be applicable to multiple linkages. For example, on weak it would produce the current behavior we have for objc metadata. On internal, it would be equivalent to private (and we should then remove private). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203866 91177308-0d34-0410-b5e6-96231b3b80d8		2014-03-13 23:18:37 +00:00
..
AsmWriter.cpp	Remove the linker_private and linker_private_weak linkages.	2014-03-13 23:18:37 +00:00
AsmWriter.h	IR: add a second ordering operand to cmpxhg for failure	2014-03-11 10:48:52 +00:00
AttributeImpl.h
Attributes.cpp
AutoUpgrade.cpp
BasicBlock.cpp
CMakeLists.txt
ConstantFold.cpp
ConstantFold.h
ConstantRange.cpp
Constants.cpp
ConstantsContext.h
Core.cpp	Remove the linker_private and linker_private_weak linkages.	2014-03-13 23:18:37 +00:00
DataLayout.cpp	[C++11] Modernize the IR library a bit.	2014-03-10 15:03:06 +00:00
DebugInfo.cpp
DebugLoc.cpp
DiagnosticInfo.cpp
DiagnosticPrinter.cpp
DIBuilder.cpp
Dominators.cpp
Function.cpp	Revert r203488 and r203520.	2014-03-12 18:09:37 +00:00
GCOV.cpp
Globals.cpp
GVMaterializer.cpp
InlineAsm.cpp	Remove copy ctors that did the same thing as the default one.	2014-03-11 11:32:49 +00:00
Instruction.cpp	IR: add a second ordering operand to cmpxhg for failure	2014-03-11 10:48:52 +00:00
Instructions.cpp	IR: add a second ordering operand to cmpxhg for failure	2014-03-11 10:48:52 +00:00
IntrinsicInst.cpp
IRBuilder.cpp
IRPrintingPasses.cpp
LeakDetector.cpp
LeaksContext.h
LegacyPassManager.cpp
LLVMBuild.txt
LLVMContext.cpp
LLVMContextImpl.cpp
LLVMContextImpl.h
Makefile
Mangler.cpp	Remove the linker_private and linker_private_weak linkages.	2014-03-13 23:18:37 +00:00
Metadata.cpp	[C++11] Modernize the IR library a bit.	2014-03-10 15:03:06 +00:00
Module.cpp	Module: Don't rename in getOrInsertFunction()	2014-03-10 23:42:28 +00:00
Pass.cpp
PassManager.cpp	[PM] Stop playing fast and loose with rebinding of references. However	2014-03-13 09:50:31 +00:00
PassRegistry.cpp
SymbolTableListTraitsImpl.h
Type.cpp
TypeFinder.cpp
Use.cpp
User.cpp
Value.cpp
ValueSymbolTable.cpp
ValueTypes.cpp
Verifier.cpp	Reject alias to undefined symbols in the verifier.	2014-03-12 20:15:49 +00:00