Fix issues with GCC debugging. GCC emits DWARF in unique ways that LLDB wasn't handling. This fix will fix cases where classes are forward declared using DW_TAG_structure_type and then actually defined using DW_TAG_class_type. LLDB, when it finds a forward declaration, would try and find and parse the complete type. It does this by:

1 - looking up the type basename in the type index
2 - iterate through all matches and look for decl contexts (namespace/class hierarchy) that match

The issue was the decl context matching wasn't watching for DW_TAG_class_type/DW_TAG_structure_type mismatches, and it wasn't also getting the name for DIE's that didn't have a DW_AT_name, but did have a DW_AT_specification that had a name.

llvm-svn: 186347

2 files changed, 18 insertions, 0 deletions

diff --git a/lldb/source/Plugins/SymbolFile/DWARF/DWARFDebugInfoEntry.cpp b/lldb/source/Plugins/SymbolFile/DWARF/DWARFDebugInfoEntry.cpp
index 7b3a6cba176..79cf0a1cd4f 100644
--- a/lldb/source/Plugins/SymbolFile/DWARF/DWARFDebugInfoEntry.cpp
+++ b/lldb/source/Plugins/SymbolFile/DWARF/DWARFDebugInfoEntry.cpp
@@ -1475,6 +1475,16 @@ DWARFDebugInfoEntry::GetName
     DWARFFormValue form_value;
     if (GetAttributeValue(dwarf2Data, cu, DW_AT_name, form_value))
         return form_value.AsCString(&dwarf2Data->get_debug_str_data());
+    else
+    {
+        if (GetAttributeValue(dwarf2Data, cu, DW_AT_specification, form_value))
+        {
+            DWARFCompileUnitSP cu_sp_ptr;
+            const DWARFDebugInfoEntry* die = const_cast<SymbolFileDWARF*>(dwarf2Data)->DebugInfo()->GetDIEPtr(form_value.Reference(cu), &cu_sp_ptr);
+            if (die)
+                return die->GetName(dwarf2Data, cu_sp_ptr.get());
+        }
+    }
     return NULL;
 }
 
diff --git a/lldb/source/Plugins/SymbolFile/DWARF/DWARFDeclContext.cpp b/lldb/source/Plugins/SymbolFile/DWARF/DWARFDeclContext.cpp
index 7d265beaab7..abf69190c93 100644
--- a/lldb/source/Plugins/SymbolFile/DWARF/DWARFDeclContext.cpp
+++ b/lldb/source/Plugins/SymbolFile/DWARF/DWARFDeclContext.cpp
@@ -82,7 +82,15 @@ DWARFDeclContext::operator==(const DWARFDeclContext& rhs) const
     for (pos = begin, rhs_pos = rhs_begin; pos != end; ++pos, ++rhs_pos)
     {
         if (pos->tag != rhs_pos->tag)
+        {
+            // Check for DW_TAG_structure_type and DW_TAG_class_type as they are often
+            // used interchangeably in GCC
+            if (pos->tag == DW_TAG_structure_type && rhs_pos->tag == DW_TAG_class_type)
+                continue;
+            if (pos->tag == DW_TAG_class_type && rhs_pos->tag == DW_TAG_structure_type)
+                continue;
             return false;
+        }
     }
     // The tags all match, now compare the names
     for (pos = begin, rhs_pos = rhs_begin; pos != end; ++pos, ++rhs_pos)