[Lldb-commits] [lldb] r344605 - Fix: Assertion failed: (!m_first_die || m_first_die == m_die_array.front()), function ExtractDIEsRWLocked

[Jan Kratochvil via lldb-commits]

Author: jankratochvil
Date: Tue Oct 16 04:38:22 2018
New Revision: 344605

URL: http://llvm.org/viewvc/llvm-project?rev=344605&view=rev
Log:
Fix: Assertion failed: (!m_first_die || m_first_die == m_die_array.front()), function ExtractDIEsRWLocked

xbolva00 bugreported $subj in: https://reviews.llvm.org/D46810#1247410
It can happen only from the line:
	m_die_array.back().SetEmptyChildren(true);

In the case DW_TAG_compile_unit has DW_CHILDREN_yes but there is only 0 (end of
list, no children present). Therefore the assertion can fortunately happen only
with a hand-crafted DWARF or with DWARF from some suboptimal compilers.

Differential Revision: https://reviews.llvm.org/D53255

Modified:
    lldb/trunk/source/Plugins/SymbolFile/DWARF/DWARFUnit.cpp

Modified: lldb/trunk/source/Plugins/SymbolFile/DWARF/DWARFUnit.cpp
URL: http://llvm.org/viewvc/llvm-project/lldb/trunk/source/Plugins/SymbolFile/DWARF/DWARFUnit.cpp?rev=344605&r1=344604&r2=344605&view=diff
==============================================================================
--- lldb/trunk/source/Plugins/SymbolFile/DWARF/DWARFUnit.cpp (original)
+++ lldb/trunk/source/Plugins/SymbolFile/DWARF/DWARFUnit.cpp Tue Oct 16 04:38:22 2018
@@ -261,7 +261,11 @@ void DWARFUnit::ExtractDIEsRWLocked() {
   }
 
   if (!m_die_array.empty()) {
-    lldbassert(!m_first_die || m_first_die == m_die_array.front());
+    if (m_first_die) {
+      // Only needed for the assertion.
+      m_first_die.SetEmptyChildren(m_die_array.front().GetEmptyChildren());
+      lldbassert(m_first_die == m_die_array.front());
+    }
     m_first_die = m_die_array.front();
   }