Index: lld/test/ELF/stdout.s
===================================================================
--- lld/test/ELF/stdout.s
+++ lld/test/ELF/stdout.s
@@ -1,12 +1,15 @@
 # REQUIRES: x86
 
 # RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t.o
-# RUN: ld.lld %t.o -o - > %t
-# RUN: llvm-objdump -d %t | FileCheck %s
+# RUN: ld.lld %t.o -o - > %t1
+# RUN: llvm-objdump -d %t1 | FileCheck %s
 
 # CHECK: 0000000000201000 _start:
 # CHECK: 201000: 90 nop
 
+# RUN: ld.lld %t.o -o %t2
+# RUN: diff %t1 %t2
+
 .globl _start
 _start:
   nop
Index: llvm/lib/Support/FileOutputBuffer.cpp
===================================================================
--- llvm/lib/Support/FileOutputBuffer.cpp
+++ llvm/lib/Support/FileOutputBuffer.cpp
@@ -77,25 +77,26 @@
 class InMemoryBuffer : public FileOutputBuffer {
 public:
   InMemoryBuffer(StringRef Path, std::unique_ptr<raw_fd_ostream> &OS,
-                 MemoryBlock MB)
-      : FileOutputBuffer(Path), OS(std::move(OS)), MB(MB) {}
+                 MemoryBlock MB, size_t Size)
+      : FileOutputBuffer(Path), OS(std::move(OS)), MB(MB), Size(Size) {}
 
   uint8_t *getBufferStart() const override { return (uint8_t *)MB.base(); }
 
   uint8_t *getBufferEnd() const override {
-    return (uint8_t *)MB.base() + MB.size();
+    return (uint8_t *)MB.base() + Size;
   }
 
-  size_t getBufferSize() const override { return MB.size(); }
+  size_t getBufferSize() const override { return Size; }
 
   Error commit() override {
-    *OS << StringRef((const char *)MB.base(), MB.size());
+    *OS << StringRef((const char *)MB.base(), Size);
     return Error::success();
   }
 
 private:
   std::unique_ptr<raw_fd_ostream> OS;
   OwningMemoryBlock MB;
+  size_t Size;
 };
 } // namespace
 
@@ -114,7 +115,7 @@
   auto OS = make_unique<raw_fd_ostream>(FD, /*shouldClose=*/true,
                                         /*unbuffered=*/true);
 
-  return llvm::make_unique<InMemoryBuffer>(Path, OS, MB);
+  return llvm::make_unique<InMemoryBuffer>(Path, OS, MB, Size);
 }
 
 static Expected<std::unique_ptr<OnDiskBuffer>>
@@ -162,7 +163,7 @@
 
     auto OS = make_unique<raw_fd_ostream>("-", EC, sys::fs::F_None);
     assert(!EC);
-    return llvm::make_unique<InMemoryBuffer>("-", OS, MB);
+    return llvm::make_unique<InMemoryBuffer>("-", OS, MB, Size);
   }
 
   unsigned Mode = fs::all_read | fs::all_write;