lld/test/ELF/linkerscript/discard-section.s

   1 # REQUIRES: x86
   2 ## Test relocations referencing symbols defined relative to sections discarded by /DISCARD/.
   3
   4 # RUN: rm -rf %t && split-file %s %t && cd %t
   5 # RUN: llvm-mc -filetype=obj -triple=x86_64 a.s -o a.o
   6 # RUN: llvm-mc -filetype=obj -triple=x86_64 b.s -o b.o
   7 # RUN: not ld.lld --threads=1 -T a.lds a.o b.o -z undefs -o /dev/null 2>&1 | FileCheck %s --check-prefix=LOCAL --implicit-check-not=error:
   8 # RUN: not ld.lld --threads=1 -T a.lds a.o b.o -o /dev/null 2>&1 | FileCheck %s --check-prefixes=LOCAL,NONLOCAL --implicit-check-not=error:
   9 # RUN: ld.lld -r -T a.lds a.o b.o -o a.ro 2>&1 | FileCheck %s --check-prefix=WARNING --implicit-check-not=warning:
  10 # RUN: llvm-readelf -r -s a.ro | FileCheck %s --check-prefix=RELOC
  11
  12 # RUN: ld.lld -r --gc-sections -T a.lds a.o b.o -o a.gc.ro --no-fatal-warnings
  13 # RUN: llvm-readelf -r -s a.gc.ro | FileCheck %s --check-prefix=RELOC-GC
  14
  15 # LOCAL:      error: relocation refers to a discarded section: .aaa
  16 # LOCAL-NEXT: >>> defined in a.o
  17 # LOCAL-NEXT: >>> referenced by a.o:(.bbb+0x0)
  18
  19 # NONLOCAL:      error: relocation refers to a symbol in a discarded section: global
  20 # NONLOCAL-NEXT: >>> defined in a.o
  21 # NONLOCAL-NEXT: >>> referenced by b.o:(.data+0x0)
  22
  23 # NONLOCAL:      error: relocation refers to a symbol in a discarded section: weak
  24 # NONLOCAL-NEXT: >>> defined in a.o
  25 # NONLOCAL-NEXT: >>> referenced by b.o:(.data+0x8)
  26
  27 # NONLOCAL:      error: relocation refers to a symbol in a discarded section: weakref1
  28 # NONLOCAL-NEXT: >>> defined in a.o
  29 # NONLOCAL-NEXT: >>> referenced by b.o:(.data+0x10)
  30
  31 # NONLOCAL:      error: relocation refers to a symbol in a discarded section: weakref2
  32 # NONLOCAL-NEXT: >>> defined in a.o
  33 # NONLOCAL-NEXT: >>> referenced by b.o:(.data+0x18)
  34
  35 # WARNING:      warning: relocation refers to a discarded section: .aaa
  36 # WARNING-NEXT: >>> referenced by a.o:(.rela.bbb+0x0)
  37
  38 ## GNU ld reports "defined in discarded secion" errors even in -r mode.
  39 ## We set the symbol index to 0.
  40 # RELOC:      Relocation section '.rela.bbb' at offset {{.*}} contains 1 entries:
  41 # RELOC-NEXT:     Offset             Info             Type               Symbol's Value  Symbol's Name + Addend
  42 # RELOC-NEXT: 0000000000000000  0000000000000000 R_X86_64_NONE                             0
  43 # RELOC-EMPTY:
  44 # RELOC-NEXT: Relocation section '.rela.data' at offset {{.*}} contains 4 entries:
  45 # RELOC-NEXT:     Offset             Info             Type               Symbol's Value  Symbol's Name + Addend
  46 # RELOC-NEXT: 0000000000000000  0000000000000001 R_X86_64_64                             0
  47 # RELOC-NEXT: 0000000000000008  0000000000000001 R_X86_64_64                             0
  48 # RELOC-NEXT: 0000000000000010  0000000000000001 R_X86_64_64                             0
  49 # RELOC-NEXT: 0000000000000018  0000000000000001 R_X86_64_64                             0
  50
  51 # RELOC:      Num:    Value          Size Type    Bind   Vis      Ndx Name
  52 # RELOC-NEXT:   0: 0000000000000000     0 NOTYPE  LOCAL  DEFAULT  UND
  53 # RELOC-NEXT:   1: 0000000000000000     0 SECTION LOCAL  DEFAULT    1 .text
  54 # RELOC-NEXT:   2: 0000000000000000     0 SECTION LOCAL  DEFAULT    2 .bbb
  55 # RELOC-NEXT:   3: 0000000000000000     0 SECTION LOCAL  DEFAULT    4 .data
  56 # RELOC-NEXT:   4: 0000000000000000     0 NOTYPE  GLOBAL DEFAULT    1 _start
  57 # RELOC-EMPTY:
  58
  59 # RELOC-GC:   There are no relocations in this file.
  60
  61 #--- a.s
  62 .globl _start
  63 _start:
  64
  65 .section .aaa,"a"
  66 .globl global, weakref1, unused
  67 .weak weak, weakref2
  68 global:
  69 weak:
  70 weakref1:
  71 weakref2:
  72 ## Eliminate `unused` just like GC discarded definitions.
  73 ## Linux kernel's CONFIG_DEBUG_FORCE_WEAK_PER_CPU=y configuration expects
  74 ## that the unreferenced `unused` is not emitted to .symtab.
  75 unused:
  76   .quad 0
  77
  78 .section .bbb,"aw"
  79   .quad .aaa
  80
  81 #--- b.s
  82 .weak weakref1, weakref2
  83 .section .data,"aw"
  84   .quad global
  85   .quad weak
  86   .quad weakref1
  87   .quad weakref2
  88
  89 #--- a.lds
  90 SECTIONS { /DISCARD/ : { *(.aaa) } }