[llvm-pdbdump] Better error handling.

Previously it was impossible to distinguish between "There is
no PDB implementation for this platform" and "I tried to load
the PDB, but couldn't find the file", making it hard to figure
out if you built llvm-pdbdump incorrectly or if you just mistyped
a file name.

This patch adds proper error handling so that we can know exactly
what went wrong.

llvm-svn: 230868

1 files changed, 4 insertions, 4 deletions

diff --git a/llvm/lib/DebugInfo/PDB/PDB.cpp b/llvm/lib/DebugInfo/PDB/PDB.cpp
index aa84c28..a07396d 100644
--- a/llvm/lib/DebugInfo/PDB/PDB.cpp
+++ b/llvm/lib/DebugInfo/PDB/PDB.cpp
@@ -20,11 +20,11 @@
 
 using namespace llvm;
 
-std::unique_ptr<IPDBSession> llvm::createPDBReader(PDB_ReaderType Type,
-                                                   StringRef Path) {
+PDB_ErrorCode llvm::createPDBReader(PDB_ReaderType Type, StringRef Path,
+                                    std::unique_ptr<IPDBSession> &Session) {
   // Create the correct concrete instance type based on the value of Type.
 #if HAVE_DIA_SDK
-  return std::unique_ptr<DIASession>(DIASession::createFromPdb(Path));
+  return DIASession::createFromPdb(Path, Session);
 #endif
-  return nullptr;
+  return PDB_ErrorCode::NoPdbImpl;
 }