Add missing vtable anchors

Summary: This patch adds anchor() for MemoryBuffer, raw_fd_ostream, RTDyldMemoryManager, SectionMemoryManager, etc.

Reviewers: jlebar, eli.friedman, dblaikie

Reviewed By: dblaikie

Subscribers: mehdi_amini, mgorny, dblaikie, weimingz, llvm-commits

Differential Revision: https://reviews.llvm.org/D45244

llvm-svn: 329861
diff --git a/llvm/lib/ExecutionEngine/MCJIT/MCJIT.cpp b/llvm/lib/ExecutionEngine/MCJIT/MCJIT.cpp
index 438e656..eb99312 100644
--- a/llvm/lib/ExecutionEngine/MCJIT/MCJIT.cpp
+++ b/llvm/lib/ExecutionEngine/MCJIT/MCJIT.cpp
@@ -28,6 +28,8 @@
 
 using namespace llvm;
 
+void llvm::ObjectMemoryBuffer::anchor() {}
+
 namespace {
 
 static struct RegisterJIT {
@@ -665,3 +667,5 @@
     return nullptr;
   return ClientResolver->findSymbol(Name);
 }
+
+void LinkingSymbolResolver::anchor() {}