Index: llvm/trunk/lib/Bitcode/Reader/BitcodeReader.cpp
===================================================================
--- llvm/trunk/lib/Bitcode/Reader/BitcodeReader.cpp
+++ llvm/trunk/lib/Bitcode/Reader/BitcodeReader.cpp
@@ -3347,7 +3347,7 @@
   assert(DeferredFunctionInfo.count(F) && "No info to read function later?");
 
   // Just forget the function body, we can remat it later.
-  F->deleteBody();
+  F->dropAllReferences();
 }
 
 std::error_code BitcodeReader::MaterializeModule(Module *M) {
Index: llvm/trunk/unittests/Bitcode/BitReaderTest.cpp
===================================================================
--- llvm/trunk/unittests/Bitcode/BitReaderTest.cpp
+++ llvm/trunk/unittests/Bitcode/BitReaderTest.cpp
@@ -58,6 +58,30 @@
   return std::unique_ptr<Module>(ModuleOrErr.get());
 }
 
+TEST(BitReaderTest, DematerializeFunctionPreservesLinkageType) {
+  SmallString<1024> Mem;
+
+  LLVMContext Context;
+  std::unique_ptr<Module> M = getLazyModuleFromAssembly(
+      Context, Mem, "define internal i32 @func() {\n"
+                      "ret i32 0\n"
+                    "}\n");
+
+  EXPECT_FALSE(verifyModule(*M, &dbgs()));
+
+  M->getFunction("func")->Materialize();
+  EXPECT_FALSE(M->getFunction("func")->empty());
+  EXPECT_TRUE(M->getFunction("func")->getLinkage() ==
+              GlobalValue::InternalLinkage);
+
+  // Check that the linkage type is preserved after dematerialization.
+  M->getFunction("func")->Dematerialize();
+  EXPECT_TRUE(M->getFunction("func")->empty());
+  EXPECT_TRUE(M->getFunction("func")->getLinkage() ==
+              GlobalValue::InternalLinkage);
+  EXPECT_FALSE(verifyModule(*M, &dbgs()));
+}
+
 TEST(BitReaderTest, MaterializeFunctionsForBlockAddr) { // PR11677
   SmallString<1024> Mem;