Index: lib/Object/Archive.cpp
===================================================================
--- lib/Object/Archive.cpp
+++ lib/Object/Archive.cpp
@@ -146,9 +146,14 @@
   ErrorOr<StringRef> Name = getName();
   if (std::error_code EC = Name.getError())
     return EC;
-  SmallString<128> FullName = sys::path::parent_path(
-      Parent->getMemoryBufferRef().getBufferIdentifier());
-  sys::path::append(FullName, *Name);
+  SmallString<128> FullName;
+  if (sys::path::is_absolute(*Name))
+    FullName = *Name;
+  else {
+    FullName = sys::path::parent_path(
+        Parent->getMemoryBufferRef().getBufferIdentifier());
+    sys::path::append(FullName, *Name);
+  }
   ErrorOr<std::unique_ptr<MemoryBuffer>> Buf = MemoryBuffer::getFile(FullName);
   if (std::error_code EC = Buf.getError())
     return EC;
Index: test/Object/archive-thin-read.test
===================================================================
--- /dev/null
+++ test/Object/archive-thin-read.test
@@ -0,0 +1,5 @@
+RUN: echo hello > %t.file
+RUN: llvm-ar rcsT %t.a %t.file
+RUN: llvm-ar p %t.a | FileCheck %s
+
+CHECK: hello