ld.lld: error: relocation R_MIPS_32 cannot be used against local symbol; recompile with -fPIC

[wzssyqa]

t.cpp

#include <stdio.h>

#include "t.h"

TT::TT(const int a)
    : n(a)
{
    printf("{%s}[%s](%d) : %d\n", __FILE__, __func__, __LINE__, n); 
}

m.cpp

#include <stdio.h>

#include "t.h"

int main()
{
    int c = 100;
    printf("{%s}[%s](%d) : %d\n", __FILE__, __func__, __LINE__, c); 
    TT *a = new TT(c);
    printf("{%s}[%s](%d) : %p\n", __FILE__, __func__, __LINE__, a); 
    return 0;
}

t.h

class TT {
public:
    //explicit TT(const int a);
    TT(const int a);
    ~TT() {};
private:
    int n {};
};

$ ../build/bin/clang++ -fPIC -mabi=32 -fuse-ld=lld -O3 -o a.out t.cpp m.cpp
ld.lld: error: relocation R_MIPS_32 cannot be used against local symbol; recompile with -fPIC
>>> defined in /tmp/m-dc13fe.o
>>> referenced by m.cpp
>>>               /tmp/m-dc13fe.o:(.eh_frame+0x2D)
clang-16: error: linker command failed with exit code 1 (use -v to see invocation)

$ ../build/bin/clang++ -fPIC -L/lib64 -mabi=64 -fuse-ld=lld -O3 -o a.out t.cpp m.cpp 
ld.lld: error: relocation R_MIPS_64 cannot be used against local symbol; recompile with -fPIC
>>> defined in /tmp/m-627e22.o
>>> referenced by m.cpp
>>>               /tmp/m-627e22.o:(.eh_frame+0x31)
clang-16: error: linker command failed with exit code 1 (use -v to see invocation)

[wzssyqa]

ld.bfd works well.

[llvmbot]

@llvm/issue-subscribers-backend-mips

[llvmbot]

@llvm/issue-subscribers-lld-elf

[MaskRay]

This is a MIPS ABI bug or compiler bug. One relocatable file has .eh_frame referencing DW.ref.__gxx_personality using the encoding DW_EH_PE_absptr. This encoding is wrong for PIC.

However, GNU ld works around the bug by converting this into DW_EH_PE_sdata4|DW_EH_PE_pcrel. ld.lld does not implement the hack, hence the error.

GCC and Clang should use DW_EH_PE_sdata4|DW_EH_PE_pcrel to reference the personality symbol.

[atanasyan]

This is an incomplete solution for the problem - https://reviews.llvm.org/D80392. It solves the but but probably we need an option to turn on/off this feature.