Merge pull request #8148 from adrian-prantl/unsupported-debuginfo

Emit a warning when parsing unsupported debug info.

Author: adrian-prantl

lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp

@@ -13,6 +13,7 @@
 #include "llvm/Support/Casting.h"
 #include "llvm/Support/Threading.h"
 
+#include "lldb/Core/Debugger.h"
 #include "lldb/Core/Module.h"
 #include "lldb/Core/ModuleList.h"
 #include "lldb/Core/ModuleSpec.h"
@@ -652,6 +653,15 @@ DWARFCompileUnit *SymbolFileDWARF::GetDWARFCompileUnit(CompileUnit *comp_unit) {
   if (dwarf_cu && dwarf_cu->GetUserData() == nullptr)
     dwarf_cu->SetUserData(comp_unit);
 
+  // This branch has several known issues in the DWARF 5 parser. Let users know.
+  if (dwarf_cu && dwarf_cu->GetVersion() > 4) {
+    static llvm::once_flag g_once_flag;
+    llvm::call_once(g_once_flag, []() {
+      Debugger::ReportError(
+          "This version of LLDB does not support DWARF version 5 or later.");
+    });
+  }
+
   // It must be DWARFCompileUnit when it created a CompileUnit.
   return llvm::cast_or_null<DWARFCompileUnit>(dwarf_cu);
 }

lldb/test/Shell/SymbolFile/DWARF/dwarf5-warning.c

@@ -0,0 +1,15 @@
+// Test that optimized flag is properly included in DWARF.
+
+// -gsplit-dwarf is supported only on Linux.
+// REQUIRES: system-darwin
+
+// This test uses lldb's embedded python interpreter
+// REQUIRES: python
+
+// RUN: %clang_host %s -g -gdwarf-5 -c -o %t.o
+// RUN: %clang_host %t.o -o %t.exe
+// RUN: %lldb %t.exe -b -o 'b main' -o r -o q 2>&1 | FileCheck %s
+
+// CHECK: error: This version of LLDB does not support DWARF version 5 or later.
+
+int main(void) { return 0; }