tree 451efa35e0feb481b4c6421ba7d760fa04749c9e
parent 896ad3a41120f0a01154da19402441e6bb2bb0ed
author Fangrui Song <maskray@google.com> 1560478493 +0000
committer Fangrui Song <maskray@google.com> 1560478493 +0000

[ELF][RISCV] Create dummy .sdata for __global_pointer$ if .sdata does not exist

If .sdata is absent, linker synthesized __global_pointer$ gets a section index of SHN_ABS.
(ld.bfd has a similar issue: binutils PR24678)

Scrt1.o may use `lla gp, __global_pointer$` to reference the symbol PC
relatively. In -pie/-shared mode, lld complains if a PC relative
relocation references an absolute symbol (SHN_ABS) but ld.bfd doesn't:

    ld.lld: error: relocation R_RISCV_PCREL_HI20 cannot refer to lute symbol: __global_pointer$

Let the reference of __global_pointer$ to force creation of .sdata to
fix the problem. This is similar to _GLOBAL_OFFSET_TABLE_, which forces
creation of .got or .got.plt .

Also, change the visibility from STV_HIDDEN to STV_DEFAULT and don't
define the symbol for -shared. This matches ld.bfd, though I don't
understand why it uses STV_DEFAULT.

Reviewed By: ruiu, jrtc27

Differential Revision: https://reviews.llvm.org/D63132

git-svn-id: https://llvm.org/svn/llvm-project/lld/trunk@363351 91177308-0d34-0410-b5e6-96231b3b80d8