fixup! add comment

Author: Michael137

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

@@ -611,6 +611,9 @@ void DWARFDebugInfoEntry::BuildFunctionAddressRangeTable(
     DWARFUnit *cu, DWARFDebugAranges *debug_aranges) const {
   Log *log = GetLog(DWARFLog::DebugInfo);
   if (m_tag) {
+    // Subprogram forward declarations don't have
+    // DW_AT_ranges/DW_AT_low_pc/DW_AT_high_pc attributes, so don't even try
+    // getting address range information for them.
     if (m_tag == DW_TAG_subprogram &&
         !GetAttributeValueAsOptionalUnsigned(cu, DW_AT_declaration)) {
       if (llvm::Expected<llvm::DWARFAddressRangesVector> ranges =