[LTO] Include bitcode symbol name in unreachable messages.

llvm-svn: 264691
diff --git a/lld/ELF/OutputSections.cpp b/lld/ELF/OutputSections.cpp
index 9421c48..82cf635 100644
--- a/lld/ELF/OutputSections.cpp
+++ b/lld/ELF/OutputSections.cpp
@@ -1505,7 +1505,7 @@
   case SymbolBody::LazyKind:
     break;
   case SymbolBody::DefinedBitcodeKind:
-    llvm_unreachable("should have been replaced");
+    llvm_unreachable("Symbol " + Sym.getName() + " should have been replaced");
   }
   return nullptr;
 }
diff --git a/lld/ELF/Symbols.cpp b/lld/ELF/Symbols.cpp
index 3ea7ceb..3835ae3 100644
--- a/lld/ELF/Symbols.cpp
+++ b/lld/ELF/Symbols.cpp
@@ -75,7 +75,7 @@
     assert(Body.isUsedInRegularObj() && "lazy symbol reached writer");
     return 0;
   case SymbolBody::DefinedBitcodeKind:
-    llvm_unreachable("should have been replaced");
+    llvm_unreachable("Symbol " + Body.getName() + " should have been replaced");
   }
   llvm_unreachable("invalid symbol kind");
 }