llvm dev - Jun 2017 - Building llvm with clang and lld on arm and the llvm arm backend relocation on position independent code

Oh, so it looks like I hit a bit of a wall there :-) I’ll take a look thanks.

That bug talks about R_ARM_THM_CALL which I assume are thumb related.

Will your implementation fix also R_ARM_CALL errors?
> On 28 Jun 2017, at 17:15, Peter Smith <peter.smith at linaro.org>
wrote:
> 
> Hello Alessandro,
> 
> The LLD ARM port doesn't currently support range extension thunks,
> these are needed to extend the range of ARM branch relocations when
> the size of the executable instructions exceeds the maximum branch
> range.
> 
> I have an implementation in review but it is a fairly large change so
> it may take some time to get through the review process, I've raised
> https://bugs.llvm.org/show_bug.cgi?id=33612 that has a link to the
> Phab reviews. If you are willing to build your own lld with additional
> changes, you might be able to test out those patches.
> 
> Good luck
> 
> Peter
> 
> On 28 June 2017 at 17:09, Alessandro Pistocchi <apukfreelance at
gmail.com> wrote:
>> 
>>> On 27 Jun 2017, at 13:25, Peter Smith <peter.smith at
linaro.org> wrote:
>>> 
>>> Hello Alessandro,
>>> 
>>> Despite the statement in the HowToCrossCompileLLVM guide "If
you’re
>>> using Clang as the cross-compiler, there is a problem in the LLVM
ARM
>>> back-end that is producing absolute relocations on
>>> position-independent code (R_ARM_THM_MOVW_ABS_NC), so for now, you
>>> should disable PIC:" I can't find an existing upstream PR
or any
>>> record that this has been fixed. If the ARM backend is still
producing
>>> an R_ARM_THM_MOVW_ABS_NC relocation when -fpic is given as an
option
>>> then it would be great to get a small reproducible example in a new
>>> PR, or if there is one already to update it.
>>> 
>>> The last time I ran into this error when trying to cross compile
was
>>> that a dependency not compiled by clang (libtinfo.a) library
contained
>>> an R_ARM_THM_MOVW_ABS_NC relocation. I don't think that this is
the
>>> fault of clang/llvm though, I think it was my fault in installing a
>>> non pic compiled version of libtinfo.a (I'm still trying to
learn how
>>> Ubuntu multilibs work).
>>> 
>>> Would it be possible for you to share the details of which objects
>>> contain the R_ARM_THM_MOVW_ABS_NC relocations when compiled -fpic?
>> 
>> Hi, the errors I get do not seen to mention R_ARM_THM_MOVW_ABS_NC.
>> 
>> The errors are “relocation R_ARM_CALL out of range”.
>> 
>> Today I recompiled everything from scratch with -fPIC to make sure I
had no library compiled without it and I still get the same errors.
>> 
>> Sorry, I could not find any trivial code that has the same issue yet.
>> 
>> Following is the output of the compilation process:
>> 
>> yawmoo at
yawmoo-MRNM3AP:~/Desktop/clfs/sources/llvm-build-native-with-lld$ cmake --build
.
>> [  0%] Built target LLVMDemangle
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>> [ 85%] Linking CXX executable ../../../../bin/clang
>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAliasAnalysis.cpp:(function
llvm::Pass* llvm::callDefaultCtor<llvm::objcarc::ObjCARCAAWrapperPass>()):
relocation R_ARM_CALL out of range
>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAliasAnalysis.cpp:(function
llvm::Pass* llvm::callDefaultCtor<llvm::objcarc::ObjCARCAAWrapperPass>()):
relocation R_ARM_CALL out of range
>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/tools/clang/lib/StaticAnalyzer/Core/CallEvent.cpp:(function
clang::ento::CXXDestructorCall*
clang::ento::CallEventManager::create<clang::ento::CXXDestructorCall,
clang::CXXDestructorDecl const*, clang::Stmt const*, clang::ento::MemRegion
const*, bool>(clang::CXXDestructorDecl const*, clang::Stmt const*,
clang::ento::MemRegion const*, bool,
llvm::IntrusiveRefCntPtr<clang::ento::ProgramState const>,
clang::LocationContext const*)): relocation R_ARM_CALL out of range
>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAliasAnalysis.cpp:(function
llvm::Pass* llvm::callDefaultCtor<llvm::objcarc::ObjCARCAAWrapperPass>()):
relocation R_ARM_CALL out of range
>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAliasAnalysis.cpp:(function
llvm::Pass* llvm::callDefaultCtor<llvm::objcarc::ObjCARCAAWrapperPass>()):
relocation R_ARM_CALL out of range
>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAliasAnalysis.cpp:(function
llvm::Pass* llvm::callDefaultCtor<llvm::objcarc::ObjCARCAAWrapperPass>()):
relocation R_ARM_CALL out of range
>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAnalysisUtils.cpp:(function
llvm::cl::opt<bool, true, llvm::cl::parser<bool> >::opt<char
[21], llvm::cl::desc, llvm::cl::LocationClass<bool>,
llvm::cl::initializer<bool> >(char const (&) [21], llvm::cl::desc
const&, llvm::cl::LocationClass<bool> const&,
llvm::cl::initializer<bool> const&)): relocation R_ARM_CALL out of
range
>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAnalysisUtils.cpp:(function
llvm::cl::opt<bool, true, llvm::cl::parser<bool> >::opt<char
[21], llvm::cl::desc, llvm::cl::LocationClass<bool>,
llvm::cl::initializer<bool> >(char const (&) [21], llvm::cl::desc
const&, llvm::cl::LocationClass<bool> const&,
llvm::cl::initializer<bool> const&)): relocation R_ARM_CALL out of
range
>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAnalysisUtils.cpp:(function
llvm::cl::opt<bool, true, llvm::cl::parser<bool> >::opt<char
[21], llvm::cl::desc, llvm::cl::LocationClass<bool>,
llvm::cl::initializer<bool> >(char const (&) [21], llvm::cl::desc
const&, llvm::cl::LocationClass<bool> const&,
llvm::cl::initializer<bool> const&)): relocation R_ARM_CALL out of
range
>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAnalysisUtils.cpp:(function
_GLOBAL__sub_I_ObjCARCAnalysisUtils.cpp): relocation R_ARM_CALL out of range
>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::operator<<(llvm::raw_ostream&,
llvm::objcarc::ARCInstKind)): relocation R_ARM_CALL out of range
>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::operator<<(llvm::raw_ostream&,
llvm::objcarc::ARCInstKind)): relocation R_ARM_CALL out of range
>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::GetFunctionClass(llvm::Function const*)): relocation R_ARM_CALL
out of range
>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/tools/clang/lib/StaticAnalyzer/Core/CallEvent.cpp:(function
clang::ento::CXXDestructorCall*
clang::ento::CallEventManager::create<clang::ento::CXXDestructorCall,
clang::CXXDestructorDecl const*, clang::Stmt const*, clang::ento::MemRegion
const*, bool>(clang::CXXDestructorDecl const*, clang::Stmt const*,
clang::ento::MemRegion const*, bool,
llvm::IntrusiveRefCntPtr<clang::ento::ProgramState const>,
clang::LocationContext const*)): relocation R_ARM_CALL out of range
>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::GetFunctionClass(llvm::Function const*)): relocation R_ARM_CALL
out of range
>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::GetFunctionClass(llvm::Function const*)): relocation R_ARM_CALL
out of range
>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::GetFunctionClass(llvm::Function const*)): relocation R_ARM_CALL
out of range
>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::GetFunctionClass(llvm::Function const*)): relocation R_ARM_CALL
out of range
>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::GetFunctionClass(llvm::Function const*)): relocation R_ARM_CALL
out of range
>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::GetFunctionClass(llvm::Function const*)): relocation R_ARM_CALL
out of range
>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error: too
many errors emitted, stopping now (use -error-limit=0 to see all errors)
>> clang-5.0: error: linker command failed with exit code 1 (use -v to see
invocation)
>> tools/clang/tools/driver/CMakeFiles/clang.dir/build.make:227: recipe
for target 'bin/clang-5.0' failed
>> make[2]: *** [bin/clang-5.0] Error 1
>> CMakeFiles/Makefile2:11670: recipe for target
'tools/clang/tools/driver/CMakeFiles/clang.dir/all' failed
>> make[1]: *** [tools/clang/tools/driver/CMakeFiles/clang.dir/all] Error
2
>> Makefile:149: recipe for target 'all' failed
>> make: *** [all] Error 2
>> yawmoo at
yawmoo-MRNM3AP:~/Desktop/clfs/sources/llvm-build-native-with-lld$
>> 
>> 
>>> 
>>> Peter
>>> 
>>> On 27 June 2017 at 11:47, Alessandro Pistocchi via llvm-dev
>>> <llvm-dev at lists.llvm.org> wrote:
>>>> 
>>>> On 26 Jun 2017, at 16:25, Rui Ueyama <ruiu at google.com>
wrote:
>>>> 
>>>> On Sun, Jun 25, 2017 at 6:40 AM, Alessandro Pistocchi via
llvm-dev
>>>> <llvm-dev at lists.llvm.org> wrote:
>>>>> 
>>>>> Hi,
>>>>> 
>>>>> I am trying to build a completely GNU free linux toolchain
for the
>>>>> raspberry pi.
>>>>> 
>>>>> I successfully managed to compile llvm and clang for armv7
hard float (
>>>>> both as a cross compiler and as a native compiler )
together with the
>>>>> following:
>>>>> 
>>>>> Llvm with clang and lld
>>>>> Clang builtins
>>>>> Musl libc
>>>>> libc++, libc++abi, libunwind
>>>>> 
>>>>> All works well with the only thing to notice being the need
to use -fPIC
>>>>> in order to access some library functions when my own c/c++
programs access
>>>>> those functions.
>>>>> 
>>>>> The fact seems to be that musl libc exports some symbols as
protected (
>>>>> probably correctly ) and lld ( probably correctly ) says it
cannot preempt
>>>>> those symbols.
>>>>> For this reason I seem to have to use -fPIC in the C and
CXX flags but
>>>>> everything seems to work ok.
>>>> 
>>>> 
>>>> Is this the same problem mentioned in
>>>> https://bugs.llvm.org/show_bug.cgi?id=32425?
>>>> 
>>>> 
>>>> My aim is to build llvm+clang+lld using llvm+clang+lld on arm (
using musl,
>>>> libc++, libc++abi, libunwind and the clang builtins, no gcc
runtime at all
>>>> ).
>>>> 
>>>> I think the fact that lld cannot preempt some symbols without
using -fPIC is
>>>> similar to the problem mentioned in
>>>> https://bugs.llvm.org/show_bug.cgi?id=32425 .
>>>> 
>>>> However I am not particularly bothered at this stage about
having to use
>>>> -fPIC. That would be fine.
>>>> 
>>>> What I am struggling with is that having to use -fPIC is in
conflict with
>>>> the arm backend issue that creates bad relocations when
building clang with
>>>> -fPIC as mentioned in
http://llvm.org/docs/HowToCrossCompileLLVM.html and so
>>>> the build with -fPIC fails when building the clang binary.
>>>> 
>>>> Regarding https://bugs.llvm.org/show_bug.cgi?id=32425 , please
notice that
>>>> contrary to what is reported there I definitely can build and
execute a C
>>>> hello world program without having to use -fPIC.
>>>> 
>>>> It is only some symbols from musl that cannot be preempted by
lld, not all
>>>> of them.
>>>> 
>>>> Unfortunately, when building llvm+clang+lld quite a few of
those symbols are
>>>> explicitly looked for by cmake and not found unless I use
-fPIC.
>>>> 
>>>> If I go ahead and build without using -fPIC then the build
fails because it
>>>> cannot preempt those symbols.
>>>> 
>>>> It looks like a paradox to me and I think the solution would be
to fix the
>>>> fact that the arm backend does not like -fPIC as mentioned in
>>>> http://llvm.org/docs/HowToCrossCompileLLVM.html . While it is
probably
>>>> correct that lld says it cannot preempt protected symbols, the
arm backend
>>>> issue is a known issue.
>>>> 
>>>> 
>>>>> 
>>>>> Then I tried to use this compiler ( both the cross compiler
and the native
>>>>> compiler ) to compile llvm + clang + lld ( I want to have
the toolchain
>>>>> built with itself, again without any GNU software involved
) but when
>>>>> building the clang executable I ran into the arm relocation
problems
>>>>> mentioned here in the “Hacks” section when using -fPIC:
>>>>> http://llvm.org/docs/HowToCrossCompileLLVM.html .
>>>>> On the other hand, I seem to need -fPIC otherwise cmake
fails to find some
>>>>> libc functions such as futimes/futimens and many others. If
I use -fPIC for
>>>>> CFLAGS but not for CXXFLAGS then cmake finds those symbols
but then
>>>>> obviously fails at a later stage with lld unable to preempt
those symbols.
>>>>> 
>>>>> This seems to be a conflict I cannot solve without someone
within the llvm
>>>>> team fixing the arm relocation problem. Is there any
estimate of when this
>>>>> could happen? I am happy to spend the time testing any
solutions by building
>>>>> my own toolchain until it succeeds. Or is there any other
solution?
>>>>> 
>>>>> Thank you,
>>>>> Alex
>>>>> 
>>>>> 
>>>>> _______________________________________________
>>>>> LLVM Developers mailing list
>>>>> llvm-dev at lists.llvm.org
>>>>> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>>>> 
>>>> 
>>>> 
>>>> _______________________________________________
>>>> LLVM Developers mailing list
>>>> llvm-dev at lists.llvm.org
>>>> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>>>> 
>>

Yes it should cover the following relocations:
R_ARM_CALL (ARM BL/BLX)
R_ARM_JUMP24 (ARM B)
R_ARM_THM_CALL (Thumb BL/BLX)
R_ARM_THM_JUMP19 (Thumb conditional B<cc>.w)
R_ARM_THM_JMP24 (Thumb unconditional B.w)

Peter


On 28 June 2017 at 17:31, Alessandro Pistocchi <apukfreelance at
gmail.com> wrote:
> Oh, so it looks like I hit a bit of a wall there :-) I’ll take a look
thanks.
>
> That bug talks about R_ARM_THM_CALL which I assume are thumb related.
>
> Will your implementation fix also R_ARM_CALL errors?
>
>> On 28 Jun 2017, at 17:15, Peter Smith <peter.smith at linaro.org>
wrote:
>>
>> Hello Alessandro,
>>
>> The LLD ARM port doesn't currently support range extension thunks,
>> these are needed to extend the range of ARM branch relocations when
>> the size of the executable instructions exceeds the maximum branch
>> range.
>>
>> I have an implementation in review but it is a fairly large change so
>> it may take some time to get through the review process, I've
raised
>> https://bugs.llvm.org/show_bug.cgi?id=33612 that has a link to the
>> Phab reviews. If you are willing to build your own lld with additional
>> changes, you might be able to test out those patches.
>>
>> Good luck
>>
>> Peter
>>
>> On 28 June 2017 at 17:09, Alessandro Pistocchi <apukfreelance at
gmail.com> wrote:
>>>
>>>> On 27 Jun 2017, at 13:25, Peter Smith <peter.smith at
linaro.org> wrote:
>>>>
>>>> Hello Alessandro,
>>>>
>>>> Despite the statement in the HowToCrossCompileLLVM guide
"If you’re
>>>> using Clang as the cross-compiler, there is a problem in the
LLVM ARM
>>>> back-end that is producing absolute relocations on
>>>> position-independent code (R_ARM_THM_MOVW_ABS_NC), so for now,
you
>>>> should disable PIC:" I can't find an existing upstream
PR or any
>>>> record that this has been fixed. If the ARM backend is still
producing
>>>> an R_ARM_THM_MOVW_ABS_NC relocation when -fpic is given as an
option
>>>> then it would be great to get a small reproducible example in a
new
>>>> PR, or if there is one already to update it.
>>>>
>>>> The last time I ran into this error when trying to cross
compile was
>>>> that a dependency not compiled by clang (libtinfo.a) library
contained
>>>> an R_ARM_THM_MOVW_ABS_NC relocation. I don't think that
this is the
>>>> fault of clang/llvm though, I think it was my fault in
installing a
>>>> non pic compiled version of libtinfo.a (I'm still trying to
learn how
>>>> Ubuntu multilibs work).
>>>>
>>>> Would it be possible for you to share the details of which
objects
>>>> contain the R_ARM_THM_MOVW_ABS_NC relocations when compiled
-fpic?
>>>
>>> Hi, the errors I get do not seen to mention R_ARM_THM_MOVW_ABS_NC.
>>>
>>> The errors are “relocation R_ARM_CALL out of range”.
>>>
>>> Today I recompiled everything from scratch with -fPIC to make sure
I had no library compiled without it and I still get the same errors.
>>>
>>> Sorry, I could not find any trivial code that has the same issue
yet.
>>>
>>> Following is the output of the compilation process:
>>>
>>> yawmoo at
yawmoo-MRNM3AP:~/Desktop/clfs/sources/llvm-build-native-with-lld$ cmake --build
.
>>> [  0%] Built target LLVMDemangle
>>> [  3%] Built target LLVMSupport
>>> [  3%] Built target LLVMTableGen
>>> [  4%] Built target obj.llvm-tblgen
>>> [  4%] Built target llvm-tblgen
>>> [  4%] Built target AttributeCompatFuncTableGen
>>> [  4%] Built target intrinsics_gen
>>> [  6%] Built target LLVMCore
>>> [  6%] Built target LLVMIRReader
>>> [ 13%] Built target LLVMCodeGen
>>> [ 14%] Built target LLVMSelectionDAG
>>> [ 14%] Built target LLVMAsmPrinter
>>> [ 14%] Built target LLVMMIRParser
>>> [ 14%] Built target LLVMGlobalISel
>>> [ 14%] Built target LLVMBinaryFormat
>>> [ 14%] Built target LLVMBitReader
>>> [ 16%] Built target LLVMBitWriter
>>> [ 18%] Built target LLVMTransformUtils
>>> [ 19%] Built target LLVMInstrumentation
>>> [ 19%] Built target LLVMInstCombine
>>> [ 22%] Built target LLVMScalarOpts
>>> [ 22%] Built target LLVMipo
>>> [ 24%] Built target LLVMVectorize
>>> [ 24%] Built target LLVMHello_exports
>>> [ 24%] Built target LLVMHello
>>> [ 26%] Built target LLVMObjCARCOpts
>>> [ 26%] Built target LLVMCoroutines
>>> [ 26%] Built target LLVMLinker
>>> [ 29%] Built target LLVMAnalysis
>>> [ 29%] Built target llvm_vcsrevision_h
>>> [ 29%] Built target LLVMLTO
>>> [ 32%] Built target LLVMMC
>>> [ 32%] Built target LLVMMCParser
>>> [ 32%] Built target LLVMMCDisassembler
>>> [ 32%] Built target LLVMObject
>>> [ 32%] Built target LLVMObjectYAML
>>> [ 34%] Built target LLVMOption
>>> [ 36%] Built target LLVMDebugInfoDWARF
>>> [ 36%] Built target LLVMDebugInfoMSF
>>> [ 37%] Built target LLVMDebugInfoCodeView
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>>> [ 42%] Built target LLVMSymbolize
>>> [ 42%] Built target LLVMExecutionEngine
>>> [ 42%] Built target LLVMInterpreter
>>> [ 42%] Built target LLVMMCJIT
>>> [ 42%] Built target LLVMOrcJIT
>>> [ 42%] Built target LLVMRuntimeDyld
>>> [ 42%] Built target LLVMTarget
>>> [ 44%] Built target ARMCommonTableGen
>>> [ 45%] Built target LLVMARMCodeGen
>>> [ 45%] Built target LLVMARMInfo
>>> [ 45%] Built target LLVMARMAsmParser
>>> [ 45%] Built target LLVMARMDisassembler
>>> [ 45%] Built target LLVMARMAsmPrinter
>>> [ 45%] Built target LLVMARMDesc
>>> [ 47%] Built target LLVMAsmParser
>>> [ 47%] Built target LLVMLineEditor
>>> [ 47%] Built target LLVMProfileData
>>> [ 47%] Built target LLVMCoverage
>>> [ 49%] Built target LLVMFuzzerNoMainObjects
>>> [ 49%] Built target LLVMFuzzerNoMain
>>> [ 49%] Built target LLVMFuzzer
>>> [ 49%] Built target LLVMPasses
>>> [ 49%] Built target LibOptionsTableGen
>>> [ 49%] Built target LLVMLibDriver
>>> [ 49%] Built target LLVMXRay
>>> [ 49%] Built target gtest
>>> [ 49%] Built target LLVMTestingSupport
>>> [ 49%] Built target FileCheck
>>> [ 49%] Built target llvm-PerfectShuffle
>>> [ 49%] Built target count
>>> [ 49%] Built target not
>>> [ 49%] Built target yaml-bench
>>> [ 49%] Built target LTO_exports
>>> [ 50%] Built target LTO
>>> [ 50%] Built target llvm-ar
>>> [ 50%] Built target llvm-ranlib
>>> [ 50%] Built target llvm-lib
>>> [ 50%] Built target llvm-config
>>> [ 50%] Built target llvm-lto
>>> [ 50%] Built target llvm-profdata
>>> [ 50%] Built target obj.clang-tblgen
>>> [ 50%] Built target clang-tblgen
>>> [ 55%] Built target clang-headers
>>> [ 55%] Built target ClangSACheckers
>>> [ 55%] Built target ClangCommentCommandList
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>>> [ 55%] Built target ClangCommentHTMLNamedCharacterReferences
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>>> [ 55%] Built target ClangStmtNodes
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>>> [ 55%] Built target ClangCommentHTMLTagsProperties
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>>> [ 55%] Built target ClangDiagnosticIndexName
>>> [ 55%] Built target ClangDiagnosticSerialization
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>>> [ 57%] Built target ClangAttrSubjectMatchRuleList
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>>> [ 59%] Built target ClangAttrParsedAttrKinds
>>> [ 59%] Built target ClangAttrSpellingListIndex
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>>> [ 60%] Built target clangBasic
>>> [ 62%] Built target clangLex
>>> [ 62%] Built target clangParse
>>> [ 63%] Built target clangAST
>>> [ 63%] Built target clangASTMatchers
>>> [ 63%] Built target clangDynamicASTMatchers
>>> [ 65%] Built target clangSema
>>> [ 67%] Built target clangCodeGen
>>> [ 68%] Built target clangAnalysis
>>> [ 68%] Built target clangEdit
>>> [ 70%] Built target clangRewrite
>>> [ 72%] Built target clangARCMigrate
>>> [ 72%] Built target ClangDriverOptions
>>> [ 75%] Built target clangDriver
>>> [ 75%] Built target clangSerialization
>>> [ 77%] Built target clangFrontend
>>> [ 77%] Built target clangRewriteFrontend
>>> [ 77%] Built target clangFrontendTool
>>> [ 77%] Built target clangTooling
>>> [ 77%] Built target clangToolingCore
>>> [ 77%] Built target clangToolingRefactor
>>> [ 77%] Built target clangIndex
>>> [ 78%] Built target clangStaticAnalyzerCore
>>> [ 83%] Built target clangStaticAnalyzerCheckers
>>> [ 83%] Built target clangStaticAnalyzerFrontend
>>> [ 83%] Built target clangFormat
>>> [ 85%] Built target diagtool
>>> [ 85%] Built target clang-offload-bundler
>>> [ 85%] Linking CXX executable ../../../../bin/clang
>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAliasAnalysis.cpp:(function
llvm::Pass* llvm::callDefaultCtor<llvm::objcarc::ObjCARCAAWrapperPass>()):
relocation R_ARM_CALL out of range
>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAliasAnalysis.cpp:(function
llvm::Pass* llvm::callDefaultCtor<llvm::objcarc::ObjCARCAAWrapperPass>()):
relocation R_ARM_CALL out of range
>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/tools/clang/lib/StaticAnalyzer/Core/CallEvent.cpp:(function
clang::ento::CXXDestructorCall*
clang::ento::CallEventManager::create<clang::ento::CXXDestructorCall,
clang::CXXDestructorDecl const*, clang::Stmt const*, clang::ento::MemRegion
const*, bool>(clang::CXXDestructorDecl const*, clang::Stmt const*,
clang::ento::MemRegion const*, bool,
llvm::IntrusiveRefCntPtr<clang::ento::ProgramState const>,
clang::LocationContext const*)): relocation R_ARM_CALL out of range
>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAliasAnalysis.cpp:(function
llvm::Pass* llvm::callDefaultCtor<llvm::objcarc::ObjCARCAAWrapperPass>()):
relocation R_ARM_CALL out of range
>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAliasAnalysis.cpp:(function
llvm::Pass* llvm::callDefaultCtor<llvm::objcarc::ObjCARCAAWrapperPass>()):
relocation R_ARM_CALL out of range
>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAliasAnalysis.cpp:(function
llvm::Pass* llvm::callDefaultCtor<llvm::objcarc::ObjCARCAAWrapperPass>()):
relocation R_ARM_CALL out of range
>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAnalysisUtils.cpp:(function
llvm::cl::opt<bool, true, llvm::cl::parser<bool> >::opt<char
[21], llvm::cl::desc, llvm::cl::LocationClass<bool>,
llvm::cl::initializer<bool> >(char const (&) [21], llvm::cl::desc
const&, llvm::cl::LocationClass<bool> const&,
llvm::cl::initializer<bool> const&)): relocation R_ARM_CALL out of
range
>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAnalysisUtils.cpp:(function
llvm::cl::opt<bool, true, llvm::cl::parser<bool> >::opt<char
[21], llvm::cl::desc, llvm::cl::LocationClass<bool>,
llvm::cl::initializer<bool> >(char const (&) [21], llvm::cl::desc
const&, llvm::cl::LocationClass<bool> const&,
llvm::cl::initializer<bool> const&)): relocation R_ARM_CALL out of
range
>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAnalysisUtils.cpp:(function
llvm::cl::opt<bool, true, llvm::cl::parser<bool> >::opt<char
[21], llvm::cl::desc, llvm::cl::LocationClass<bool>,
llvm::cl::initializer<bool> >(char const (&) [21], llvm::cl::desc
const&, llvm::cl::LocationClass<bool> const&,
llvm::cl::initializer<bool> const&)): relocation R_ARM_CALL out of
range
>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAnalysisUtils.cpp:(function
_GLOBAL__sub_I_ObjCARCAnalysisUtils.cpp): relocation R_ARM_CALL out of range
>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::operator<<(llvm::raw_ostream&,
llvm::objcarc::ARCInstKind)): relocation R_ARM_CALL out of range
>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::operator<<(llvm::raw_ostream&,
llvm::objcarc::ARCInstKind)): relocation R_ARM_CALL out of range
>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::GetFunctionClass(llvm::Function const*)): relocation R_ARM_CALL
out of range
>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/tools/clang/lib/StaticAnalyzer/Core/CallEvent.cpp:(function
clang::ento::CXXDestructorCall*
clang::ento::CallEventManager::create<clang::ento::CXXDestructorCall,
clang::CXXDestructorDecl const*, clang::Stmt const*, clang::ento::MemRegion
const*, bool>(clang::CXXDestructorDecl const*, clang::Stmt const*,
clang::ento::MemRegion const*, bool,
llvm::IntrusiveRefCntPtr<clang::ento::ProgramState const>,
clang::LocationContext const*)): relocation R_ARM_CALL out of range
>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::GetFunctionClass(llvm::Function const*)): relocation R_ARM_CALL
out of range
>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::GetFunctionClass(llvm::Function const*)): relocation R_ARM_CALL
out of range
>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::GetFunctionClass(llvm::Function const*)): relocation R_ARM_CALL
out of range
>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::GetFunctionClass(llvm::Function const*)): relocation R_ARM_CALL
out of range
>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::GetFunctionClass(llvm::Function const*)): relocation R_ARM_CALL
out of range
>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::GetFunctionClass(llvm::Function const*)): relocation R_ARM_CALL
out of range
>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld: error:
too many errors emitted, stopping now (use -error-limit=0 to see all errors)
>>> clang-5.0: error: linker command failed with exit code 1 (use -v to
see invocation)
>>> tools/clang/tools/driver/CMakeFiles/clang.dir/build.make:227:
recipe for target 'bin/clang-5.0' failed
>>> make[2]: *** [bin/clang-5.0] Error 1
>>> CMakeFiles/Makefile2:11670: recipe for target
'tools/clang/tools/driver/CMakeFiles/clang.dir/all' failed
>>> make[1]: *** [tools/clang/tools/driver/CMakeFiles/clang.dir/all]
Error 2
>>> Makefile:149: recipe for target 'all' failed
>>> make: *** [all] Error 2
>>> yawmoo at
yawmoo-MRNM3AP:~/Desktop/clfs/sources/llvm-build-native-with-lld$
>>>
>>>
>>>>
>>>> Peter
>>>>
>>>> On 27 June 2017 at 11:47, Alessandro Pistocchi via llvm-dev
>>>> <llvm-dev at lists.llvm.org> wrote:
>>>>>
>>>>> On 26 Jun 2017, at 16:25, Rui Ueyama <ruiu at
google.com> wrote:
>>>>>
>>>>> On Sun, Jun 25, 2017 at 6:40 AM, Alessandro Pistocchi via
llvm-dev
>>>>> <llvm-dev at lists.llvm.org> wrote:
>>>>>>
>>>>>> Hi,
>>>>>>
>>>>>> I am trying to build a completely GNU free linux
toolchain for the
>>>>>> raspberry pi.
>>>>>>
>>>>>> I successfully managed to compile llvm and clang for
armv7 hard float (
>>>>>> both as a cross compiler and as a native compiler )
together with the
>>>>>> following:
>>>>>>
>>>>>> Llvm with clang and lld
>>>>>> Clang builtins
>>>>>> Musl libc
>>>>>> libc++, libc++abi, libunwind
>>>>>>
>>>>>> All works well with the only thing to notice being the
need to use -fPIC
>>>>>> in order to access some library functions when my own
c/c++ programs access
>>>>>> those functions.
>>>>>>
>>>>>> The fact seems to be that musl libc exports some
symbols as protected (
>>>>>> probably correctly ) and lld ( probably correctly )
says it cannot preempt
>>>>>> those symbols.
>>>>>> For this reason I seem to have to use -fPIC in the C
and CXX flags but
>>>>>> everything seems to work ok.
>>>>>
>>>>>
>>>>> Is this the same problem mentioned in
>>>>> https://bugs.llvm.org/show_bug.cgi?id=32425?
>>>>>
>>>>>
>>>>> My aim is to build llvm+clang+lld using llvm+clang+lld on
arm ( using musl,
>>>>> libc++, libc++abi, libunwind and the clang builtins, no gcc
runtime at all
>>>>> ).
>>>>>
>>>>> I think the fact that lld cannot preempt some symbols
without using -fPIC is
>>>>> similar to the problem mentioned in
>>>>> https://bugs.llvm.org/show_bug.cgi?id=32425 .
>>>>>
>>>>> However I am not particularly bothered at this stage about
having to use
>>>>> -fPIC. That would be fine.
>>>>>
>>>>> What I am struggling with is that having to use -fPIC is in
conflict with
>>>>> the arm backend issue that creates bad relocations when
building clang with
>>>>> -fPIC as mentioned in
http://llvm.org/docs/HowToCrossCompileLLVM.html and so
>>>>> the build with -fPIC fails when building the clang binary.
>>>>>
>>>>> Regarding https://bugs.llvm.org/show_bug.cgi?id=32425 ,
please notice that
>>>>> contrary to what is reported there I definitely can build
and execute a C
>>>>> hello world program without having to use -fPIC.
>>>>>
>>>>> It is only some symbols from musl that cannot be preempted
by lld, not all
>>>>> of them.
>>>>>
>>>>> Unfortunately, when building llvm+clang+lld quite a few of
those symbols are
>>>>> explicitly looked for by cmake and not found unless I use
-fPIC.
>>>>>
>>>>> If I go ahead and build without using -fPIC then the build
fails because it
>>>>> cannot preempt those symbols.
>>>>>
>>>>> It looks like a paradox to me and I think the solution
would be to fix the
>>>>> fact that the arm backend does not like -fPIC as mentioned
in
>>>>> http://llvm.org/docs/HowToCrossCompileLLVM.html . While it
is probably
>>>>> correct that lld says it cannot preempt protected symbols,
the arm backend
>>>>> issue is a known issue.
>>>>>
>>>>>
>>>>>>
>>>>>> Then I tried to use this compiler ( both the cross
compiler and the native
>>>>>> compiler ) to compile llvm + clang + lld ( I want to
have the toolchain
>>>>>> built with itself, again without any GNU software
involved ) but when
>>>>>> building the clang executable I ran into the arm
relocation problems
>>>>>> mentioned here in the “Hacks” section when using -fPIC:
>>>>>> http://llvm.org/docs/HowToCrossCompileLLVM.html .
>>>>>> On the other hand, I seem to need -fPIC otherwise cmake
fails to find some
>>>>>> libc functions such as futimes/futimens and many
others. If I use -fPIC for
>>>>>> CFLAGS but not for CXXFLAGS then cmake finds those
symbols but then
>>>>>> obviously fails at a later stage with lld unable to
preempt those symbols.
>>>>>>
>>>>>> This seems to be a conflict I cannot solve without
someone within the llvm
>>>>>> team fixing the arm relocation problem. Is there any
estimate of when this
>>>>>> could happen? I am happy to spend the time testing any
solutions by building
>>>>>> my own toolchain until it succeeds. Or is there any
other solution?
>>>>>>
>>>>>> Thank you,
>>>>>> Alex
>>>>>>
>>>>>>
>>>>>> _______________________________________________
>>>>>> LLVM Developers mailing list
>>>>>> llvm-dev at lists.llvm.org
>>>>>> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>>>>>
>>>>>
>>>>>
>>>>> _______________________________________________
>>>>> LLVM Developers mailing list
>>>>> llvm-dev at lists.llvm.org
>>>>> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>>>>>
>>>
>

Cool thanks I'll give it a go :-)

Sent from my iPhone
> On 28 Jun 2017, at 18:36, Peter Smith <peter.smith at linaro.org>
wrote:
> 
> Yes it should cover the following relocations:
> R_ARM_CALL (ARM BL/BLX)
> R_ARM_JUMP24 (ARM B)
> R_ARM_THM_CALL (Thumb BL/BLX)
> R_ARM_THM_JUMP19 (Thumb conditional B<cc>.w)
> R_ARM_THM_JMP24 (Thumb unconditional B.w)
> 
> Peter
> 
> 
>> On 28 June 2017 at 17:31, Alessandro Pistocchi <apukfreelance at
gmail.com> wrote:
>> Oh, so it looks like I hit a bit of a wall there :-) I’ll take a look
thanks.
>> 
>> That bug talks about R_ARM_THM_CALL which I assume are thumb related.
>> 
>> Will your implementation fix also R_ARM_CALL errors?
>> 
>>> On 28 Jun 2017, at 17:15, Peter Smith <peter.smith at
linaro.org> wrote:
>>> 
>>> Hello Alessandro,
>>> 
>>> The LLD ARM port doesn't currently support range extension
thunks,
>>> these are needed to extend the range of ARM branch relocations when
>>> the size of the executable instructions exceeds the maximum branch
>>> range.
>>> 
>>> I have an implementation in review but it is a fairly large change
so
>>> it may take some time to get through the review process, I've
raised
>>> https://bugs.llvm.org/show_bug.cgi?id=33612 that has a link to the
>>> Phab reviews. If you are willing to build your own lld with
additional
>>> changes, you might be able to test out those patches.
>>> 
>>> Good luck
>>> 
>>> Peter
>>> 
>>>> On 28 June 2017 at 17:09, Alessandro Pistocchi
<apukfreelance at gmail.com> wrote:
>>>> 
>>>>> On 27 Jun 2017, at 13:25, Peter Smith <peter.smith at
linaro.org> wrote:
>>>>> 
>>>>> Hello Alessandro,
>>>>> 
>>>>> Despite the statement in the HowToCrossCompileLLVM guide
"If you’re
>>>>> using Clang as the cross-compiler, there is a problem in
the LLVM ARM
>>>>> back-end that is producing absolute relocations on
>>>>> position-independent code (R_ARM_THM_MOVW_ABS_NC), so for
now, you
>>>>> should disable PIC:" I can't find an existing
upstream PR or any
>>>>> record that this has been fixed. If the ARM backend is
still producing
>>>>> an R_ARM_THM_MOVW_ABS_NC relocation when -fpic is given as
an option
>>>>> then it would be great to get a small reproducible example
in a new
>>>>> PR, or if there is one already to update it.
>>>>> 
>>>>> The last time I ran into this error when trying to cross
compile was
>>>>> that a dependency not compiled by clang (libtinfo.a)
library contained
>>>>> an R_ARM_THM_MOVW_ABS_NC relocation. I don't think that
this is the
>>>>> fault of clang/llvm though, I think it was my fault in
installing a
>>>>> non pic compiled version of libtinfo.a (I'm still
trying to learn how
>>>>> Ubuntu multilibs work).
>>>>> 
>>>>> Would it be possible for you to share the details of which
objects
>>>>> contain the R_ARM_THM_MOVW_ABS_NC relocations when compiled
-fpic?
>>>> 
>>>> Hi, the errors I get do not seen to mention
R_ARM_THM_MOVW_ABS_NC.
>>>> 
>>>> The errors are “relocation R_ARM_CALL out of range”.
>>>> 
>>>> Today I recompiled everything from scratch with -fPIC to make
sure I had no library compiled without it and I still get the same errors.
>>>> 
>>>> Sorry, I could not find any trivial code that has the same
issue yet.
>>>> 
>>>> Following is the output of the compilation process:
>>>> 
>>>> yawmoo at
yawmoo-MRNM3AP:~/Desktop/clfs/sources/llvm-build-native-with-lld$ cmake --build
.
>>>> [  0%] Built target LLVMDemangle
>>>> [  3%] Built target LLVMSupport
>>>> [  3%] Built target LLVMTableGen
>>>> [  4%] Built target obj.llvm-tblgen
>>>> [  4%] Built target llvm-tblgen
>>>> [  4%] Built target AttributeCompatFuncTableGen
>>>> [  4%] Built target intrinsics_gen
>>>> [  6%] Built target LLVMCore
>>>> [  6%] Built target LLVMIRReader
>>>> [ 13%] Built target LLVMCodeGen
>>>> [ 14%] Built target LLVMSelectionDAG
>>>> [ 14%] Built target LLVMAsmPrinter
>>>> [ 14%] Built target LLVMMIRParser
>>>> [ 14%] Built target LLVMGlobalISel
>>>> [ 14%] Built target LLVMBinaryFormat
>>>> [ 14%] Built target LLVMBitReader
>>>> [ 16%] Built target LLVMBitWriter
>>>> [ 18%] Built target LLVMTransformUtils
>>>> [ 19%] Built target LLVMInstrumentation
>>>> [ 19%] Built target LLVMInstCombine
>>>> [ 22%] Built target LLVMScalarOpts
>>>> [ 22%] Built target LLVMipo
>>>> [ 24%] Built target LLVMVectorize
>>>> [ 24%] Built target LLVMHello_exports
>>>> [ 24%] Built target LLVMHello
>>>> [ 26%] Built target LLVMObjCARCOpts
>>>> [ 26%] Built target LLVMCoroutines
>>>> [ 26%] Built target LLVMLinker
>>>> [ 29%] Built target LLVMAnalysis
>>>> [ 29%] Built target llvm_vcsrevision_h
>>>> [ 29%] Built target LLVMLTO
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>>>> [ 85%] Linking CXX executable ../../../../bin/clang
>>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAliasAnalysis.cpp:(function
llvm::Pass* llvm::callDefaultCtor<llvm::objcarc::ObjCARCAAWrapperPass>()):
relocation R_ARM_CALL out of range
>>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAliasAnalysis.cpp:(function
llvm::Pass* llvm::callDefaultCtor<llvm::objcarc::ObjCARCAAWrapperPass>()):
relocation R_ARM_CALL out of range
>>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/tools/clang/lib/StaticAnalyzer/Core/CallEvent.cpp:(function
clang::ento::CXXDestructorCall*
clang::ento::CallEventManager::create<clang::ento::CXXDestructorCall,
clang::CXXDestructorDecl const*, clang::Stmt const*, clang::ento::MemRegion
const*, bool>(clang::CXXDestructorDecl const*, clang::Stmt const*,
clang::ento::MemRegion const*, bool,
llvm::IntrusiveRefCntPtr<clang::ento::ProgramState const>,
clang::LocationContext const*)): relocation R_ARM_CALL out of range
>>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAliasAnalysis.cpp:(function
llvm::Pass* llvm::callDefaultCtor<llvm::objcarc::ObjCARCAAWrapperPass>()):
relocation R_ARM_CALL out of range
>>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAliasAnalysis.cpp:(function
llvm::Pass* llvm::callDefaultCtor<llvm::objcarc::ObjCARCAAWrapperPass>()):
relocation R_ARM_CALL out of range
>>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAliasAnalysis.cpp:(function
llvm::Pass* llvm::callDefaultCtor<llvm::objcarc::ObjCARCAAWrapperPass>()):
relocation R_ARM_CALL out of range
>>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAnalysisUtils.cpp:(function
llvm::cl::opt<bool, true, llvm::cl::parser<bool> >::opt<char
[21], llvm::cl::desc, llvm::cl::LocationClass<bool>,
llvm::cl::initializer<bool> >(char const (&) [21], llvm::cl::desc
const&, llvm::cl::LocationClass<bool> const&,
llvm::cl::initializer<bool> const&)): relocation R_ARM_CALL out of
range
>>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAnalysisUtils.cpp:(function
llvm::cl::opt<bool, true, llvm::cl::parser<bool> >::opt<char
[21], llvm::cl::desc, llvm::cl::LocationClass<bool>,
llvm::cl::initializer<bool> >(char const (&) [21], llvm::cl::desc
const&, llvm::cl::LocationClass<bool> const&,
llvm::cl::initializer<bool> const&)): relocation R_ARM_CALL out of
range
>>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAnalysisUtils.cpp:(function
llvm::cl::opt<bool, true, llvm::cl::parser<bool> >::opt<char
[21], llvm::cl::desc, llvm::cl::LocationClass<bool>,
llvm::cl::initializer<bool> >(char const (&) [21], llvm::cl::desc
const&, llvm::cl::LocationClass<bool> const&,
llvm::cl::initializer<bool> const&)): relocation R_ARM_CALL out of
range
>>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAnalysisUtils.cpp:(function
_GLOBAL__sub_I_ObjCARCAnalysisUtils.cpp): relocation R_ARM_CALL out of range
>>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::operator<<(llvm::raw_ostream&,
llvm::objcarc::ARCInstKind)): relocation R_ARM_CALL out of range
>>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::operator<<(llvm::raw_ostream&,
llvm::objcarc::ARCInstKind)): relocation R_ARM_CALL out of range
>>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::GetFunctionClass(llvm::Function const*)): relocation R_ARM_CALL
out of range
>>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/tools/clang/lib/StaticAnalyzer/Core/CallEvent.cpp:(function
clang::ento::CXXDestructorCall*
clang::ento::CallEventManager::create<clang::ento::CXXDestructorCall,
clang::CXXDestructorDecl const*, clang::Stmt const*, clang::ento::MemRegion
const*, bool>(clang::CXXDestructorDecl const*, clang::Stmt const*,
clang::ento::MemRegion const*, bool,
llvm::IntrusiveRefCntPtr<clang::ento::ProgramState const>,
clang::LocationContext const*)): relocation R_ARM_CALL out of range
>>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::GetFunctionClass(llvm::Function const*)): relocation R_ARM_CALL
out of range
>>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::GetFunctionClass(llvm::Function const*)): relocation R_ARM_CALL
out of range
>>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::GetFunctionClass(llvm::Function const*)): relocation R_ARM_CALL
out of range
>>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::GetFunctionClass(llvm::Function const*)): relocation R_ARM_CALL
out of range
>>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::GetFunctionClass(llvm::Function const*)): relocation R_ARM_CALL
out of range
>>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::GetFunctionClass(llvm::Function const*)): relocation R_ARM_CALL
out of range
>>>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error: too many errors emitted, stopping now (use -error-limit=0 to see all
errors)
>>>> clang-5.0: error: linker command failed with exit code 1 (use
-v to see invocation)
>>>> tools/clang/tools/driver/CMakeFiles/clang.dir/build.make:227:
recipe for target 'bin/clang-5.0' failed
>>>> make[2]: *** [bin/clang-5.0] Error 1
>>>> CMakeFiles/Makefile2:11670: recipe for target
'tools/clang/tools/driver/CMakeFiles/clang.dir/all' failed
>>>> make[1]: ***
[tools/clang/tools/driver/CMakeFiles/clang.dir/all] Error 2
>>>> Makefile:149: recipe for target 'all' failed
>>>> make: *** [all] Error 2
>>>> yawmoo at
yawmoo-MRNM3AP:~/Desktop/clfs/sources/llvm-build-native-with-lld$
>>>> 
>>>> 
>>>>> 
>>>>> Peter
>>>>> 
>>>>> On 27 June 2017 at 11:47, Alessandro Pistocchi via llvm-dev
>>>>> <llvm-dev at lists.llvm.org> wrote:
>>>>>> 
>>>>>> On 26 Jun 2017, at 16:25, Rui Ueyama <ruiu at
google.com> wrote:
>>>>>> 
>>>>>> On Sun, Jun 25, 2017 at 6:40 AM, Alessandro Pistocchi
via llvm-dev
>>>>>> <llvm-dev at lists.llvm.org> wrote:
>>>>>>> 
>>>>>>> Hi,
>>>>>>> 
>>>>>>> I am trying to build a completely GNU free linux
toolchain for the
>>>>>>> raspberry pi.
>>>>>>> 
>>>>>>> I successfully managed to compile llvm and clang
for armv7 hard float (
>>>>>>> both as a cross compiler and as a native compiler )
together with the
>>>>>>> following:
>>>>>>> 
>>>>>>> Llvm with clang and lld
>>>>>>> Clang builtins
>>>>>>> Musl libc
>>>>>>> libc++, libc++abi, libunwind
>>>>>>> 
>>>>>>> All works well with the only thing to notice being
the need to use -fPIC
>>>>>>> in order to access some library functions when my
own c/c++ programs access
>>>>>>> those functions.
>>>>>>> 
>>>>>>> The fact seems to be that musl libc exports some
symbols as protected (
>>>>>>> probably correctly ) and lld ( probably correctly )
says it cannot preempt
>>>>>>> those symbols.
>>>>>>> For this reason I seem to have to use -fPIC in the
C and CXX flags but
>>>>>>> everything seems to work ok.
>>>>>> 
>>>>>> 
>>>>>> Is this the same problem mentioned in
>>>>>> https://bugs.llvm.org/show_bug.cgi?id=32425?
>>>>>> 
>>>>>> 
>>>>>> My aim is to build llvm+clang+lld using llvm+clang+lld
on arm ( using musl,
>>>>>> libc++, libc++abi, libunwind and the clang builtins, no
gcc runtime at all
>>>>>> ).
>>>>>> 
>>>>>> I think the fact that lld cannot preempt some symbols
without using -fPIC is
>>>>>> similar to the problem mentioned in
>>>>>> https://bugs.llvm.org/show_bug.cgi?id=32425 .
>>>>>> 
>>>>>> However I am not particularly bothered at this stage
about having to use
>>>>>> -fPIC. That would be fine.
>>>>>> 
>>>>>> What I am struggling with is that having to use -fPIC
is in conflict with
>>>>>> the arm backend issue that creates bad relocations when
building clang with
>>>>>> -fPIC as mentioned in
http://llvm.org/docs/HowToCrossCompileLLVM.html and so
>>>>>> the build with -fPIC fails when building the clang
binary.
>>>>>> 
>>>>>> Regarding https://bugs.llvm.org/show_bug.cgi?id=32425 ,
please notice that
>>>>>> contrary to what is reported there I definitely can
build and execute a C
>>>>>> hello world program without having to use -fPIC.
>>>>>> 
>>>>>> It is only some symbols from musl that cannot be
preempted by lld, not all
>>>>>> of them.
>>>>>> 
>>>>>> Unfortunately, when building llvm+clang+lld quite a few
of those symbols are
>>>>>> explicitly looked for by cmake and not found unless I
use -fPIC.
>>>>>> 
>>>>>> If I go ahead and build without using -fPIC then the
build fails because it
>>>>>> cannot preempt those symbols.
>>>>>> 
>>>>>> It looks like a paradox to me and I think the solution
would be to fix the
>>>>>> fact that the arm backend does not like -fPIC as
mentioned in
>>>>>> http://llvm.org/docs/HowToCrossCompileLLVM.html . While
it is probably
>>>>>> correct that lld says it cannot preempt protected
symbols, the arm backend
>>>>>> issue is a known issue.
>>>>>> 
>>>>>> 
>>>>>>> 
>>>>>>> Then I tried to use this compiler ( both the cross
compiler and the native
>>>>>>> compiler ) to compile llvm + clang + lld ( I want
to have the toolchain
>>>>>>> built with itself, again without any GNU software
involved ) but when
>>>>>>> building the clang executable I ran into the arm
relocation problems
>>>>>>> mentioned here in the “Hacks” section when using
-fPIC:
>>>>>>> http://llvm.org/docs/HowToCrossCompileLLVM.html .
>>>>>>> On the other hand, I seem to need -fPIC otherwise
cmake fails to find some
>>>>>>> libc functions such as futimes/futimens and many
others. If I use -fPIC for
>>>>>>> CFLAGS but not for CXXFLAGS then cmake finds those
symbols but then
>>>>>>> obviously fails at a later stage with lld unable to
preempt those symbols.
>>>>>>> 
>>>>>>> This seems to be a conflict I cannot solve without
someone within the llvm
>>>>>>> team fixing the arm relocation problem. Is there
any estimate of when this
>>>>>>> could happen? I am happy to spend the time testing
any solutions by building
>>>>>>> my own toolchain until it succeeds. Or is there any
other solution?
>>>>>>> 
>>>>>>> Thank you,
>>>>>>> Alex
>>>>>>> 
>>>>>>> 
>>>>>>> _______________________________________________
>>>>>>> LLVM Developers mailing list
>>>>>>> llvm-dev at lists.llvm.org
>>>>>>>
http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>>>>>> 
>>>>>> 
>>>>>> 
>>>>>> _______________________________________________
>>>>>> LLVM Developers mailing list
>>>>>> llvm-dev at lists.llvm.org
>>>>>> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>>>>>> 
>>>> 
>>

I've successfully used Peter's patches to get past those relocation
errors.

On 6/28/17, 9:36 AM, "llvm-dev on behalf of Peter Smith via llvm-dev"
<llvm-dev-bounces at lists.llvm.org on behalf of llvm-dev at
lists.llvm.org> wrote:

    Yes it should cover the following relocations:
    R_ARM_CALL (ARM BL/BLX)
    R_ARM_JUMP24 (ARM B)
    R_ARM_THM_CALL (Thumb BL/BLX)
    R_ARM_THM_JUMP19 (Thumb conditional B<cc>.w)
    R_ARM_THM_JMP24 (Thumb unconditional B.w)
    
    Peter
    
    
    On 28 June 2017 at 17:31, Alessandro Pistocchi <apukfreelance at
gmail.com> wrote:
    > Oh, so it looks like I hit a bit of a wall there :-) I’ll take a look
thanks.
    >
    > That bug talks about R_ARM_THM_CALL which I assume are thumb related.
    >
    > Will your implementation fix also R_ARM_CALL errors?
    >
    >> On 28 Jun 2017, at 17:15, Peter Smith <peter.smith at
linaro.org> wrote:
    >>
    >> Hello Alessandro,
    >>
    >> The LLD ARM port doesn't currently support range extension
thunks,
    >> these are needed to extend the range of ARM branch relocations when
    >> the size of the executable instructions exceeds the maximum branch
    >> range.
    >>
    >> I have an implementation in review but it is a fairly large change
so
    >> it may take some time to get through the review process, I've
raised
    >>
https://urldefense.proofpoint.com/v2/url?u=https-3A__bugs.llvm.org_show-5Fbug.cgi-3Fid-3D33612&d=DwIGaQ&c=5VD0RTtNlTh3ycd41b3MUw&r=o3kDXzdBUE3ljQXKeTWOMw&m=MoG8NHuM6pLu1J1B-yHnV-uqDvXgdp72ydIhDlNyQ9Q&s=RpqKAJtCInfokC4ejkvv1e1hbMx22g7c6-v8JNuzOrY&e=
that has a link to the
    >> Phab reviews. If you are willing to build your own lld with
additional
    >> changes, you might be able to test out those patches.
    >>
    >> Good luck
    >>
    >> Peter
    >>
    >> On 28 June 2017 at 17:09, Alessandro Pistocchi <apukfreelance at
gmail.com> wrote:
    >>>
    >>>> On 27 Jun 2017, at 13:25, Peter Smith <peter.smith at
linaro.org> wrote:
    >>>>
    >>>> Hello Alessandro,
    >>>>
    >>>> Despite the statement in the HowToCrossCompileLLVM guide
"If you’re
    >>>> using Clang as the cross-compiler, there is a problem in
the LLVM ARM
    >>>> back-end that is producing absolute relocations on
    >>>> position-independent code (R_ARM_THM_MOVW_ABS_NC), so for
now, you
    >>>> should disable PIC:" I can't find an existing
upstream PR or any
    >>>> record that this has been fixed. If the ARM backend is
still producing
    >>>> an R_ARM_THM_MOVW_ABS_NC relocation when -fpic is given as
an option
    >>>> then it would be great to get a small reproducible example
in a new
    >>>> PR, or if there is one already to update it.
    >>>>
    >>>> The last time I ran into this error when trying to cross
compile was
    >>>> that a dependency not compiled by clang (libtinfo.a)
library contained
    >>>> an R_ARM_THM_MOVW_ABS_NC relocation. I don't think that
this is the
    >>>> fault of clang/llvm though, I think it was my fault in
installing a
    >>>> non pic compiled version of libtinfo.a (I'm still
trying to learn how
    >>>> Ubuntu multilibs work).
    >>>>
    >>>> Would it be possible for you to share the details of which
objects
    >>>> contain the R_ARM_THM_MOVW_ABS_NC relocations when compiled
-fpic?
    >>>
    >>> Hi, the errors I get do not seen to mention
R_ARM_THM_MOVW_ABS_NC.
    >>>
    >>> The errors are “relocation R_ARM_CALL out of range”.
    >>>
    >>> Today I recompiled everything from scratch with -fPIC to make
sure I had no library compiled without it and I still get the same errors.
    >>>
    >>> Sorry, I could not find any trivial code that has the same
issue yet.
    >>>
    >>> Following is the output of the compilation process:
    >>>
    >>> yawmoo at
yawmoo-MRNM3AP:~/Desktop/clfs/sources/llvm-build-native-with-lld$ cmake --build
.
    >>> [  0%] Built target LLVMDemangle
    >>> [  3%] Built target LLVMSupport
    >>> [  3%] Built target LLVMTableGen
    >>> [  4%] Built target obj.llvm-tblgen
    >>> [  4%] Built target llvm-tblgen
    >>> [  4%] Built target AttributeCompatFuncTableGen
    >>> [  4%] Built target intrinsics_gen
    >>> [  6%] Built target LLVMCore
    >>> [  6%] Built target LLVMIRReader
    >>> [ 13%] Built target LLVMCodeGen
    >>> [ 14%] Built target LLVMSelectionDAG
    >>> [ 14%] Built target LLVMAsmPrinter
    >>> [ 14%] Built target LLVMMIRParser
    >>> [ 14%] Built target LLVMGlobalISel
    >>> [ 14%] Built target LLVMBinaryFormat
    >>> [ 14%] Built target LLVMBitReader
    >>> [ 16%] Built target LLVMBitWriter
    >>> [ 18%] Built target LLVMTransformUtils
    >>> [ 19%] Built target LLVMInstrumentation
    >>> [ 19%] Built target LLVMInstCombine
    >>> [ 22%] Built target LLVMScalarOpts
    >>> [ 22%] Built target LLVMipo
    >>> [ 24%] Built target LLVMVectorize
    >>> [ 24%] Built target LLVMHello_exports
    >>> [ 24%] Built target LLVMHello
    >>> [ 26%] Built target LLVMObjCARCOpts
    >>> [ 26%] Built target LLVMCoroutines
    >>> [ 26%] Built target LLVMLinker
    >>> [ 29%] Built target LLVMAnalysis
    >>> [ 29%] Built target llvm_vcsrevision_h
    >>> [ 29%] Built target LLVMLTO
    >>> [ 32%] Built target LLVMMC
    >>> [ 32%] Built target LLVMMCParser
    >>> [ 32%] Built target LLVMMCDisassembler
    >>> [ 32%] Built target LLVMObject
    >>> [ 32%] Built target LLVMObjectYAML
    >>> [ 34%] Built target LLVMOption
    >>> [ 36%] Built target LLVMDebugInfoDWARF
    >>> [ 36%] Built target LLVMDebugInfoMSF
    >>> [ 37%] Built target LLVMDebugInfoCodeView
    >>> [ 40%] Built target LLVMDebugInfoPDB
    >>> [ 42%] Built target LLVMSymbolize
    >>> [ 42%] Built target LLVMExecutionEngine
    >>> [ 42%] Built target LLVMInterpreter
    >>> [ 42%] Built target LLVMMCJIT
    >>> [ 42%] Built target LLVMOrcJIT
    >>> [ 42%] Built target LLVMRuntimeDyld
    >>> [ 42%] Built target LLVMTarget
    >>> [ 44%] Built target ARMCommonTableGen
    >>> [ 45%] Built target LLVMARMCodeGen
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    >>> [ 47%] Built target LLVMProfileData
    >>> [ 47%] Built target LLVMCoverage
    >>> [ 49%] Built target LLVMFuzzerNoMainObjects
    >>> [ 49%] Built target LLVMFuzzerNoMain
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    >>> [ 49%] Built target LLVMPasses
    >>> [ 49%] Built target LibOptionsTableGen
    >>> [ 49%] Built target LLVMLibDriver
    >>> [ 49%] Built target LLVMXRay
    >>> [ 49%] Built target gtest
    >>> [ 49%] Built target LLVMTestingSupport
    >>> [ 49%] Built target FileCheck
    >>> [ 49%] Built target llvm-PerfectShuffle
    >>> [ 49%] Built target count
    >>> [ 49%] Built target not
    >>> [ 49%] Built target yaml-bench
    >>> [ 49%] Built target LTO_exports
    >>> [ 50%] Built target LTO
    >>> [ 50%] Built target llvm-ar
    >>> [ 50%] Built target llvm-ranlib
    >>> [ 50%] Built target llvm-lib
    >>> [ 50%] Built target llvm-config
    >>> [ 50%] Built target llvm-lto
    >>> [ 50%] Built target llvm-profdata
    >>> [ 50%] Built target obj.clang-tblgen
    >>> [ 50%] Built target clang-tblgen
    >>> [ 55%] Built target clang-headers
    >>> [ 55%] Built target ClangSACheckers
    >>> [ 55%] Built target ClangCommentCommandList
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    >>> [ 83%] Built target clangFormat
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    >>> [ 85%] Built target clang-offload-bundler
    >>> [ 85%] Linking CXX executable ../../../../bin/clang
    >>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAliasAnalysis.cpp:(function
llvm::Pass* llvm::callDefaultCtor<llvm::objcarc::ObjCARCAAWrapperPass>()):
relocation R_ARM_CALL out of range
    >>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAliasAnalysis.cpp:(function
llvm::Pass* llvm::callDefaultCtor<llvm::objcarc::ObjCARCAAWrapperPass>()):
relocation R_ARM_CALL out of range
    >>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/tools/clang/lib/StaticAnalyzer/Core/CallEvent.cpp:(function
clang::ento::CXXDestructorCall*
clang::ento::CallEventManager::create<clang::ento::CXXDestructorCall,
clang::CXXDestructorDecl const*, clang::Stmt const*, clang::ento::MemRegion
const*, bool>(clang::CXXDestructorDecl const*, clang::Stmt const*,
clang::ento::MemRegion const*, bool,
llvm::IntrusiveRefCntPtr<clang::ento::ProgramState const>,
clang::LocationContext const*)): relocation R_ARM_CALL out of range
    >>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAliasAnalysis.cpp:(function
llvm::Pass* llvm::callDefaultCtor<llvm::objcarc::ObjCARCAAWrapperPass>()):
relocation R_ARM_CALL out of range
    >>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAliasAnalysis.cpp:(function
llvm::Pass* llvm::callDefaultCtor<llvm::objcarc::ObjCARCAAWrapperPass>()):
relocation R_ARM_CALL out of range
    >>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAliasAnalysis.cpp:(function
llvm::Pass* llvm::callDefaultCtor<llvm::objcarc::ObjCARCAAWrapperPass>()):
relocation R_ARM_CALL out of range
    >>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAnalysisUtils.cpp:(function
llvm::cl::opt<bool, true, llvm::cl::parser<bool> >::opt<char
[21], llvm::cl::desc, llvm::cl::LocationClass<bool>,
llvm::cl::initializer<bool> >(char const (&) [21], llvm::cl::desc
const&, llvm::cl::LocationClass<bool> const&,
llvm::cl::initializer<bool> const&)): relocation R_ARM_CALL out of
range
    >>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAnalysisUtils.cpp:(function
llvm::cl::opt<bool, true, llvm::cl::parser<bool> >::opt<char
[21], llvm::cl::desc, llvm::cl::LocationClass<bool>,
llvm::cl::initializer<bool> >(char const (&) [21], llvm::cl::desc
const&, llvm::cl::LocationClass<bool> const&,
llvm::cl::initializer<bool> const&)): relocation R_ARM_CALL out of
range
    >>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAnalysisUtils.cpp:(function
llvm::cl::opt<bool, true, llvm::cl::parser<bool> >::opt<char
[21], llvm::cl::desc, llvm::cl::LocationClass<bool>,
llvm::cl::initializer<bool> >(char const (&) [21], llvm::cl::desc
const&, llvm::cl::LocationClass<bool> const&,
llvm::cl::initializer<bool> const&)): relocation R_ARM_CALL out of
range
    >>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCAnalysisUtils.cpp:(function
_GLOBAL__sub_I_ObjCARCAnalysisUtils.cpp): relocation R_ARM_CALL out of range
    >>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::operator<<(llvm::raw_ostream&,
llvm::objcarc::ARCInstKind)): relocation R_ARM_CALL out of range
    >>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::operator<<(llvm::raw_ostream&,
llvm::objcarc::ARCInstKind)): relocation R_ARM_CALL out of range
    >>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::GetFunctionClass(llvm::Function const*)): relocation R_ARM_CALL
out of range
    >>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/tools/clang/lib/StaticAnalyzer/Core/CallEvent.cpp:(function
clang::ento::CXXDestructorCall*
clang::ento::CallEventManager::create<clang::ento::CXXDestructorCall,
clang::CXXDestructorDecl const*, clang::Stmt const*, clang::ento::MemRegion
const*, bool>(clang::CXXDestructorDecl const*, clang::Stmt const*,
clang::ento::MemRegion const*, bool,
llvm::IntrusiveRefCntPtr<clang::ento::ProgramState const>,
clang::LocationContext const*)): relocation R_ARM_CALL out of range
    >>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::GetFunctionClass(llvm::Function const*)): relocation R_ARM_CALL
out of range
    >>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::GetFunctionClass(llvm::Function const*)): relocation R_ARM_CALL
out of range
    >>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::GetFunctionClass(llvm::Function const*)): relocation R_ARM_CALL
out of range
    >>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::GetFunctionClass(llvm::Function const*)): relocation R_ARM_CALL
out of range
    >>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::GetFunctionClass(llvm::Function const*)): relocation R_ARM_CALL
out of range
    >>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error:
/home/yawmoo/Desktop/clfs/sources/llvm/lib/Analysis/ObjCARCInstKind.cpp:(function
llvm::objcarc::GetFunctionClass(llvm::Function const*)): relocation R_ARM_CALL
out of range
    >>> /home/yawmoo/Desktop/clfs/llvm-cross-tools-lld/bin/ld.lld:
error: too many errors emitted, stopping now (use -error-limit=0 to see all
errors)
    >>> clang-5.0: error: linker command failed with exit code 1 (use
-v to see invocation)
    >>> tools/clang/tools/driver/CMakeFiles/clang.dir/build.make:227:
recipe for target 'bin/clang-5.0' failed
    >>> make[2]: *** [bin/clang-5.0] Error 1
    >>> CMakeFiles/Makefile2:11670: recipe for target
'tools/clang/tools/driver/CMakeFiles/clang.dir/all' failed
    >>> make[1]: ***
[tools/clang/tools/driver/CMakeFiles/clang.dir/all] Error 2
    >>> Makefile:149: recipe for target 'all' failed
    >>> make: *** [all] Error 2
    >>> yawmoo at
yawmoo-MRNM3AP:~/Desktop/clfs/sources/llvm-build-native-with-lld$
    >>>
    >>>
    >>>>
    >>>> Peter
    >>>>
    >>>> On 27 June 2017 at 11:47, Alessandro Pistocchi via llvm-dev
    >>>> <llvm-dev at lists.llvm.org> wrote:
    >>>>>
    >>>>> On 26 Jun 2017, at 16:25, Rui Ueyama <ruiu at
google.com> wrote:
    >>>>>
    >>>>> On Sun, Jun 25, 2017 at 6:40 AM, Alessandro Pistocchi
via llvm-dev
    >>>>> <llvm-dev at lists.llvm.org> wrote:
    >>>>>>
    >>>>>> Hi,
    >>>>>>
    >>>>>> I am trying to build a completely GNU free linux
toolchain for the
    >>>>>> raspberry pi.
    >>>>>>
    >>>>>> I successfully managed to compile llvm and clang
for armv7 hard float (
    >>>>>> both as a cross compiler and as a native compiler )
together with the
    >>>>>> following:
    >>>>>>
    >>>>>> Llvm with clang and lld
    >>>>>> Clang builtins
    >>>>>> Musl libc
    >>>>>> libc++, libc++abi, libunwind
    >>>>>>
    >>>>>> All works well with the only thing to notice being
the need to use -fPIC
    >>>>>> in order to access some library functions when my
own c/c++ programs access
    >>>>>> those functions.
    >>>>>>
    >>>>>> The fact seems to be that musl libc exports some
symbols as protected (
    >>>>>> probably correctly ) and lld ( probably correctly )
says it cannot preempt
    >>>>>> those symbols.
    >>>>>> For this reason I seem to have to use -fPIC in the
C and CXX flags but
    >>>>>> everything seems to work ok.
    >>>>>
    >>>>>
    >>>>> Is this the same problem mentioned in
    >>>>>
https://urldefense.proofpoint.com/v2/url?u=https-3A__bugs.llvm.org_show-5Fbug.cgi-3Fid-3D32425-3F&d=DwIGaQ&c=5VD0RTtNlTh3ycd41b3MUw&r=o3kDXzdBUE3ljQXKeTWOMw&m=MoG8NHuM6pLu1J1B-yHnV-uqDvXgdp72ydIhDlNyQ9Q&s=NukMRJ9yTsw5j3ENYmb5P6xnVjqZDGr_RtEBf88y-aI&e=
    >>>>>
    >>>>>
    >>>>> My aim is to build llvm+clang+lld using llvm+clang+lld
on arm ( using musl,
    >>>>> libc++, libc++abi, libunwind and the clang builtins, no
gcc runtime at all
    >>>>> ).
    >>>>>
    >>>>> I think the fact that lld cannot preempt some symbols
without using -fPIC is
    >>>>> similar to the problem mentioned in
    >>>>>
https://urldefense.proofpoint.com/v2/url?u=https-3A__bugs.llvm.org_show-5Fbug.cgi-3Fid-3D32425&d=DwIGaQ&c=5VD0RTtNlTh3ycd41b3MUw&r=o3kDXzdBUE3ljQXKeTWOMw&m=MoG8NHuM6pLu1J1B-yHnV-uqDvXgdp72ydIhDlNyQ9Q&s=9sykAqiCyyRAxvbFBkT7xc41tFV4gbqVNlLPtuZwgEo&e=
.
    >>>>>
    >>>>> However I am not particularly bothered at this stage
about having to use
    >>>>> -fPIC. That would be fine.
    >>>>>
    >>>>> What I am struggling with is that having to use -fPIC
is in conflict with
    >>>>> the arm backend issue that creates bad relocations when
building clang with
    >>>>> -fPIC as mentioned in
https://urldefense.proofpoint.com/v2/url?u=http-3A__llvm.org_docs_HowToCrossCompileLLVM.html&d=DwIGaQ&c=5VD0RTtNlTh3ycd41b3MUw&r=o3kDXzdBUE3ljQXKeTWOMw&m=MoG8NHuM6pLu1J1B-yHnV-uqDvXgdp72ydIhDlNyQ9Q&s=ZDjTpKgbVvk-6KPfK36_iXsQkmN0tZo-GFLmojAfWdI&e=
and so
    >>>>> the build with -fPIC fails when building the clang
binary.
    >>>>>
    >>>>> Regarding
https://urldefense.proofpoint.com/v2/url?u=https-3A__bugs.llvm.org_show-5Fbug.cgi-3Fid-3D32425&d=DwIGaQ&c=5VD0RTtNlTh3ycd41b3MUw&r=o3kDXzdBUE3ljQXKeTWOMw&m=MoG8NHuM6pLu1J1B-yHnV-uqDvXgdp72ydIhDlNyQ9Q&s=9sykAqiCyyRAxvbFBkT7xc41tFV4gbqVNlLPtuZwgEo&e=
, please notice that
    >>>>> contrary to what is reported there I definitely can
build and execute a C
    >>>>> hello world program without having to use -fPIC.
    >>>>>
    >>>>> It is only some symbols from musl that cannot be
preempted by lld, not all
    >>>>> of them.
    >>>>>
    >>>>> Unfortunately, when building llvm+clang+lld quite a few
of those symbols are
    >>>>> explicitly looked for by cmake and not found unless I
use -fPIC.
    >>>>>
    >>>>> If I go ahead and build without using -fPIC then the
build fails because it
    >>>>> cannot preempt those symbols.
    >>>>>
    >>>>> It looks like a paradox to me and I think the solution
would be to fix the
    >>>>> fact that the arm backend does not like -fPIC as
mentioned in
    >>>>>
https://urldefense.proofpoint.com/v2/url?u=http-3A__llvm.org_docs_HowToCrossCompileLLVM.html&d=DwIGaQ&c=5VD0RTtNlTh3ycd41b3MUw&r=o3kDXzdBUE3ljQXKeTWOMw&m=MoG8NHuM6pLu1J1B-yHnV-uqDvXgdp72ydIhDlNyQ9Q&s=ZDjTpKgbVvk-6KPfK36_iXsQkmN0tZo-GFLmojAfWdI&e=
. While it is probably
    >>>>> correct that lld says it cannot preempt protected
symbols, the arm backend
    >>>>> issue is a known issue.
    >>>>>
    >>>>>
    >>>>>>
    >>>>>> Then I tried to use this compiler ( both the cross
compiler and the native
    >>>>>> compiler ) to compile llvm + clang + lld ( I want
to have the toolchain
    >>>>>> built with itself, again without any GNU software
involved ) but when
    >>>>>> building the clang executable I ran into the arm
relocation problems
    >>>>>> mentioned here in the “Hacks” section when using
-fPIC:
    >>>>>>
https://urldefense.proofpoint.com/v2/url?u=http-3A__llvm.org_docs_HowToCrossCompileLLVM.html&d=DwIGaQ&c=5VD0RTtNlTh3ycd41b3MUw&r=o3kDXzdBUE3ljQXKeTWOMw&m=MoG8NHuM6pLu1J1B-yHnV-uqDvXgdp72ydIhDlNyQ9Q&s=ZDjTpKgbVvk-6KPfK36_iXsQkmN0tZo-GFLmojAfWdI&e=
.
    >>>>>> On the other hand, I seem to need -fPIC otherwise
cmake fails to find some
    >>>>>> libc functions such as futimes/futimens and many
others. If I use -fPIC for
    >>>>>> CFLAGS but not for CXXFLAGS then cmake finds those
symbols but then
    >>>>>> obviously fails at a later stage with lld unable to
preempt those symbols.
    >>>>>>
    >>>>>> This seems to be a conflict I cannot solve without
someone within the llvm
    >>>>>> team fixing the arm relocation problem. Is there
any estimate of when this
    >>>>>> could happen? I am happy to spend the time testing
any solutions by building
    >>>>>> my own toolchain until it succeeds. Or is there any
other solution?
    >>>>>>
    >>>>>> Thank you,
    >>>>>> Alex
    >>>>>>
    >>>>>>
    >>>>>> _______________________________________________
    >>>>>> LLVM Developers mailing list
    >>>>>> llvm-dev at lists.llvm.org
    >>>>>>
https://urldefense.proofpoint.com/v2/url?u=http-3A__lists.llvm.org_cgi-2Dbin_mailman_listinfo_llvm-2Ddev&d=DwIGaQ&c=5VD0RTtNlTh3ycd41b3MUw&r=o3kDXzdBUE3ljQXKeTWOMw&m=MoG8NHuM6pLu1J1B-yHnV-uqDvXgdp72ydIhDlNyQ9Q&s=elMtK81LIlpU0bdvd9Zwk2UtgI9He36ddrHDrVDKt94&e=
    >>>>>
    >>>>>
    >>>>>
    >>>>> _______________________________________________
    >>>>> LLVM Developers mailing list
    >>>>> llvm-dev at lists.llvm.org
    >>>>>
https://urldefense.proofpoint.com/v2/url?u=http-3A__lists.llvm.org_cgi-2Dbin_mailman_listinfo_llvm-2Ddev&d=DwIGaQ&c=5VD0RTtNlTh3ycd41b3MUw&r=o3kDXzdBUE3ljQXKeTWOMw&m=MoG8NHuM6pLu1J1B-yHnV-uqDvXgdp72ydIhDlNyQ9Q&s=elMtK81LIlpU0bdvd9Zwk2UtgI9He36ddrHDrVDKt94&e=
    >>>>>
    >>>
    >
    _______________________________________________
    LLVM Developers mailing list
    llvm-dev at lists.llvm.org
   
https://urldefense.proofpoint.com/v2/url?u=http-3A__lists.llvm.org_cgi-2Dbin_mailman_listinfo_llvm-2Ddev&d=DwIGaQ&c=5VD0RTtNlTh3ycd41b3MUw&r=o3kDXzdBUE3ljQXKeTWOMw&m=MoG8NHuM6pLu1J1B-yHnV-uqDvXgdp72ydIhDlNyQ9Q&s=elMtK81LIlpU0bdvd9Zwk2UtgI9He36ddrHDrVDKt94&e=