[NativePDB] Don't fail on import modules.

A recent patch to LLD started emitting information about import modules.
These are represented as compile units in the PDB, but with no
additional debug info.  This was confusing the native pdb reader, who
expected that the debug info stream be present.

This should fix failing tests on the Windows bots.

llvm-svn: 357513

1 files changed, 11 insertions, 2 deletions

diff --git a/lldb/source/Plugins/SymbolFile/NativePDB/CompileUnitIndex.cpp b/lldb/source/Plugins/SymbolFile/NativePDB/CompileUnitIndex.cpp
index c8e530353fe..1838204e4ca 100644
--- a/lldb/source/Plugins/SymbolFile/NativePDB/CompileUnitIndex.cpp
+++ b/lldb/source/Plugins/SymbolFile/NativePDB/CompileUnitIndex.cpp
@@ -124,11 +124,20 @@ CompilandIndexItem &CompileUnitIndex::GetOrCreateCompiland(uint16_t modi) {
   uint16_t stream = descriptor.getModuleStreamIndex();
   std::unique_ptr<llvm::msf::MappedBlockStream> stream_data =
       m_index.pdb().createIndexedStream(stream);
+
+
+  std::unique_ptr<CompilandIndexItem>& cci = result.first->second;
+
+  if (!stream_data) {
+    llvm::pdb::ModuleDebugStreamRef debug_stream(descriptor, nullptr);
+    cci = llvm::make_unique<CompilandIndexItem>(PdbCompilandId{ modi }, debug_stream, std::move(descriptor));
+    return *cci;
+  }
+
   llvm::pdb::ModuleDebugStreamRef debug_stream(descriptor,
                                                std::move(stream_data));
-  cantFail(debug_stream.reload());
 
-  std::unique_ptr<CompilandIndexItem> &cci = result.first->second;
+  cantFail(debug_stream.reload());
 
   cci = llvm::make_unique<CompilandIndexItem>(
       PdbCompilandId{modi}, std::move(debug_stream), std::move(descriptor));