diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp index dfb36fa1d432a2b32d3111aca13bda618eade550..99ed096d132560c3eec62f6552731d3c55c6c362 100644 --- a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp +++ b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp @@ -2020,8 +2020,11 @@ void DwarfDebug::emitDebugMacinfo() { auto *SkCU = TheCU.getSkeleton(); DwarfCompileUnit &U = SkCU ? *SkCU : TheCU; auto *CUNode = cast<DICompileUnit>(P.first); - Asm->OutStreamer->EmitLabel(U.getMacroLabelBegin()); - handleMacroNodes(CUNode->getMacros(), U); + DIMacroNodeArray Macros = CUNode->getMacros(); + if (!Macros.empty()) { + Asm->OutStreamer->EmitLabel(U.getMacroLabelBegin()); + handleMacroNodes(Macros, U); + } } Asm->OutStreamer->AddComment("End Of Macro List Mark"); Asm->EmitInt8(0); diff --git a/test/DebugInfo/X86/empty_macinfo.ll b/test/DebugInfo/X86/empty_macinfo.ll new file mode 100644 index 0000000000000000000000000000000000000000..c3161f3d9e687da79c054b63acae39057fcb6695 --- /dev/null +++ b/test/DebugInfo/X86/empty_macinfo.ll @@ -0,0 +1,24 @@ +; RUN: llc -mtriple x86_64-pc-linux < %s -dwarf-version 4 | FileCheck %s + +; Test that we don't pollute the start of the file with debug sections + +; CHECK: .section .debug_macinfo,"",@progbits +; CHECK-NEXT: .byte 0 # End Of Macro List Mark +; CHECK-NEXT: .section +; CHECK-NOT: .debug_macinfo + +define void @f() !dbg !4 { + ret void, !dbg !9 +} +!llvm.dbg.cu = !{!0} +!llvm.module.flags = !{!7, !8} + +!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "foo", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, retainedTypes: !2, globals: !2, imports: !2) +!1 = !DIFile(filename: "/foo/test.c", directory: "/foo") +!2 = !{} +!4 = distinct !DISubprogram(name: "f", scope: !1, file: !1, line: 1, type: !5, isLocal: false, isDefinition: true, scopeLine: 1, flags: DIFlagPrototyped, isOptimized: true, unit: !0, variables: !2) +!5 = !DISubroutineType(types: !6) +!6 = !{null} +!7 = !{i32 2, !"Dwarf Version", i32 4} +!8 = !{i32 2, !"Debug Info Version", i32 3} +!9 = !DILocation(line: 1, column: 15, scope: !4)