[Bug ld/27016] x86-64: GOTPCREL relaxation with abs symbol and REX byte creates incorrect code

[hjl.tools at gmail dot com]

https://sourceware.org/bugzilla/show_bug.cgi?id=27016

H.J. Lu <hjl.tools at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |WAITING
                 CC|                            |hjl.tools at gmail dot com

--- Comment #2 from H.J. Lu <hjl.tools at gmail dot com> ---
I can't reproduce it with binutils master branch:

[hjl@gnu-cfl-2 pr27016]$ cat pr27016a.s
        .text
        .comm   global_int,4,4
        .globl  main
        .type   main, @function
main:
        .cfi_startproc
        pushq   %rbp
        .cfi_def_cfa_offset 16
        .cfi_offset 6, -16
        movq    %rsp, %rbp
        .cfi_def_cfa_register 6
        movq    thesym@GOTPCREL(%rip), %r11
        movl    (%r11), %eax
        leal    1(%rax), %edx
        movq    thesym@GOTPCREL(%rip), %r11
        movl    %edx, (%r11)
        movl    $0, %eax
        popq    %rbp
        .cfi_def_cfa 7, 8
        ret
        .cfi_endproc
        .size   main, .-main
        .section        .note.GNU-stack,"",@progbits
[hjl@gnu-cfl-2 pr27016]$ cat pr27016b.s
        .globl thesym
thesym = 0x40402c

        .section        .note.GNU-stack,"",@progbits
[hjl@gnu-cfl-2 pr27016]$ make
as -mrelax-relocations=no  -o pr27016a.o pr27016a.s
as -mrelax-relocations=no  -o pr27016b.o pr27016b.s
/usr/gcc-9.3.1-x32/bin/gcc -B./ -o x pr27016a.o pr27016b.o -Wl,-R,.
objdump -dwr pr27016a.o

pr27016a.o:     file format elf64-x86-64


Disassembly of section .text:

0000000000000000 <main>:
   0:   55                      push   %rbp
   1:   48 89 e5                mov    %rsp,%rbp
   4:   4c 8b 1d 00 00 00 00    mov    0x0(%rip),%r11        # b <main+0xb>    
7: R_X86_64_GOTPCREL    thesym-0x4
   b:   41 8b 03                mov    (%r11),%eax
   e:   8d 50 01                lea    0x1(%rax),%edx
  11:   4c 8b 1d 00 00 00 00    mov    0x0(%rip),%r11        # 18 <main+0x18>  
14: R_X86_64_GOTPCREL   thesym-0x4
  18:   41 89 13                mov    %edx,(%r11)
  1b:   b8 00 00 00 00          mov    $0x0,%eax
  20:   5d                      pop    %rbp
  21:   c3                      ret    
objdump --disassemble=main x

x:     file format elf64-x86-64


Disassembly of section .init:

Disassembly of section .text:

0000000000400596 <main>:
  400596:       55                      push   %rbp
  400597:       48 89 e5                mov    %rsp,%rbp
  40059a:       4c 8d 1d 8b 3a 00 00    lea    0x3a8b(%rip),%r11        #
40402c <thesym>
  4005a1:       41 8b 03                mov    (%r11),%eax
  4005a4:       8d 50 01                lea    0x1(%rax),%edx
  4005a7:       4c 8d 1d 7e 3a 00 00    lea    0x3a7e(%rip),%r11        #
40402c <thesym>
  4005ae:       41 89 13                mov    %edx,(%r11)
  4005b1:       b8 00 00 00 00          mov    $0x0,%eax
  4005b6:       5d                      pop    %rbp
  4005b7:       c3                      ret    

Disassembly of section .fini:
[hjl@gnu-cfl-2 pr27016]$

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