Fix the debug build breakage that getDiscriminator is called by mistake.

llvm-svn: 253597
diff --git a/llvm/lib/Transforms/Utils/AddDiscriminators.cpp b/llvm/lib/Transforms/Utils/AddDiscriminators.cpp
index ed9ff5a..0262358 100644
--- a/llvm/lib/Transforms/Utils/AddDiscriminators.cpp
+++ b/llvm/lib/Transforms/Utils/AddDiscriminators.cpp
@@ -205,7 +205,8 @@
       I.setDebugLoc(DILocation::get(Ctx, DIL->getLine(), DIL->getColumn(),
                                     NewScope, DIL->getInlinedAt()));
       DEBUG(dbgs() << DIL->getFilename() << ":" << DIL->getLine() << ":"
-                   << DIL->getColumn() << ":" << NewScope->getDiscriminator()
+                   << DIL->getColumn() << ":"
+                   << dyn_cast<DILexicalBlockFile>(NewScope)->getDiscriminator()
                    << I << "\n");
       Changed = true;
     }