[PATCH] D100440: [Debug-Info] DW_AT_export_symbols shouldn't be generated before version-5 of DWARF.

[EsmeYi via Phabricator via llvm-commits]

Esme created this revision.
Esme added reviewers: shchenz, aprantl, dblaikie, jsji, PowerPC.
Herald added a subscriber: hiraditya.
Esme requested review of this revision.
Herald added a project: LLVM.
Herald added a subscriber: llvm-commits.

`DW_AT_export_symbols` is an attribute introduced in DWARF-5, which should not be generated under previous DWARF versions. And this unexpected behavior caused the DBX to fail.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D100440

Files:
  llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
  llvm/test/DebugInfo/Generic/export-symbol-anonymous-class.ll


Index: llvm/test/DebugInfo/Generic/export-symbol-anonymous-class.ll
===================================================================
--- llvm/test/DebugInfo/Generic/export-symbol-anonymous-class.ll
+++ llvm/test/DebugInfo/Generic/export-symbol-anonymous-class.ll
@@ -38,6 +38,6 @@
 !10 = !{!11}
 !11 = !DIDerivedType(tag: DW_TAG_member, name: "y", scope: !9, file: !3, line: 3, baseType: !12, size: 32)
 !12 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
-!14 = !{i32 2, !"Dwarf Version", i32 4}
+!14 = !{i32 2, !"Dwarf Version", i32 5}
 !15 = !{i32 2, !"Debug Info Version", i32 3}
 !16 = !{!"clang version 10.0.0"}
Index: llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
===================================================================
--- llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
+++ llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
@@ -930,7 +930,7 @@
     if (CTy->isAppleBlockExtension())
       addFlag(Buffer, dwarf::DW_AT_APPLE_block);
 
-    if (CTy->getExportSymbols())
+    if (CTy->getExportSymbols() && DD->getDwarfVersion() >= 5)
       addFlag(Buffer, dwarf::DW_AT_export_symbols);
 
     // This is outside the DWARF spec, but GDB expects a DW_AT_containing_type
@@ -1064,7 +1064,7 @@
     Name = "(anonymous namespace)";
   DD->addAccelNamespace(*CUNode, Name, NDie);
   addGlobalName(Name, NDie, NS->getScope());
-  if (NS->getExportSymbols())
+  if (NS->getExportSymbols() && DD->getDwarfVersion() >= 5)
     addFlag(NDie, dwarf::DW_AT_export_symbols);
   return &NDie;
 }


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D100440.337322.patch
Type: text/x-patch
Size: 1502 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20210414/ef33b40e/attachment.bin>