Do not generate information for DWO ID 0

Author: Jinjie-Huang

bolt/lib/Core/BinaryContext.cpp

@@ -1628,12 +1628,15 @@ void BinaryContext::preprocessDWODebugInfo() {
   for (const std::unique_ptr<DWARFUnit> &CU : DwCtx->compile_units()) {
     DWARFUnit *const DwarfUnit = CU.get();
     if (std::optional<uint64_t> DWOId = DwarfUnit->getDWOId()) {
-      if (*DWOId == 0)
-          continue;
       std::string DWOName = dwarf::toString(
           DwarfUnit->getUnitDIE().find(
               {dwarf::DW_AT_dwo_name, dwarf::DW_AT_GNU_dwo_name}),
           "");
+      if (*DWOId == 0) {
+        this->outs() << "BOLT-WARNING: Found DWO file of ID 0: '" << DWOName
+                     << "', it will not be processed.\n";
+        continue;
+      }
       SmallString<16> AbsolutePath;
       if (!opts::CompDirOverride.empty()) {
         sys::path::append(AbsolutePath, opts::CompDirOverride);