diff --git a/llvm/lib/Target/ARM/MCTargetDesc/ARMELFObjectWriter.cpp b/llvm/lib/Target/ARM/MCTargetDesc/ARMELFObjectWriter.cpp --- a/llvm/lib/Target/ARM/MCTargetDesc/ARMELFObjectWriter.cpp +++ b/llvm/lib/Target/ARM/MCTargetDesc/ARMELFObjectWriter.cpp @@ -93,8 +93,15 @@ switch (Modifier) { default: llvm_unreachable("Unsupported Modifier"); - case MCSymbolRefExpr::VK_None: + case MCSymbolRefExpr::VK_None: { + if (const MCSymbolRefExpr *SymRef = Target.getSymA()) { + // For GNU AS compatibility expressions such as + // _GLOBAL_OFFSET_TABLE_ - label emit a R_ARM_BASE_PREL relocation. + if (SymRef->getSymbol().getName() == "_GLOBAL_OFFSET_TABLE_") + return ELF::R_ARM_BASE_PREL; + } return ELF::R_ARM_REL32; + } case MCSymbolRefExpr::VK_GOTTPOFF: return ELF::R_ARM_TLS_IE32; case MCSymbolRefExpr::VK_ARM_GOT_PREL: diff --git a/llvm/test/MC/ARM/symbol-variants.s b/llvm/test/MC/ARM/symbol-variants.s --- a/llvm/test/MC/ARM/symbol-variants.s +++ b/llvm/test/MC/ARM/symbol-variants.s @@ -96,8 +96,16 @@ @CHECK: 70 R_ARM_TLS_LDM32 f28 @CHECK: 74 R_ARM_TLS_LDM32 f29 +@ relative +.word f30 - (.Lsym+8) +@CHECK: 78 R_ARM_REL32 f30 + +@ _GLOBAL_OFFSET_TABLE_ relative +.word _GLOBAL_OFFSET_TABLE_ - (.Lsym+8) +@CHECK: 7c R_ARM_BASE_PREL _GLOBAL_OFFSET_TABLE_ + @ got_prel -.word f30(GOT_PREL) + (. - .Lsym) - ldr r3, =f31(GOT_PREL) -@ CHECK: 78 R_ARM_GOT_PREL f30 -@ CHECK: 80 R_ARM_GOT_PREL f31 +.word f31(GOT_PREL) + (. - .Lsym) + ldr r3, =f32(GOT_PREL) +@CHECK: 80 R_ARM_GOT_PREL f31 +@CHECK: 88 R_ARM_GOT_PREL f32