Fix five of the shared library build targets

Before this patch there was a cyclic dependency between lldCore and
lldReaderWriter.  Only lldConfig could be built as a shared library.

* Moved Reader and Writer base classes into lldCore.
* The following shared libraries can now be built:
     lldCore
     lldYAML
     lldNative
     lldPasses
     lldReaderWriter

Differential Revision: http://reviews.llvm.org/D7105

From: Greg Fitzgerald <garious@gmail.com>
llvm-svn: 226732

1 files changed, 23 insertions, 0 deletions

diff --git a/lld/lib/Core/Writer.cpp b/lld/lib/Core/Writer.cpp
new file mode 100644
index 00000000000..39bcc9e6852
--- /dev/null
+++ b/lld/lib/Core/Writer.cpp
@@ -0,0 +1,23 @@
+//===- lib/Core/Writer.cpp ------------------------------------------------===//
+//
+//                             The LLVM Linker
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "lld/Core/File.h"
+#include "lld/Core/Writer.h"
+
+namespace lld {
+Writer::Writer() {
+}
+
+Writer::~Writer() {
+}
+
+bool Writer::createImplicitFiles(std::vector<std::unique_ptr<File> > &) {
+  return true;
+}
+} // end namespace lld