Index: llvm/lib/Linker/IRMover.cpp
===================================================================
--- llvm/lib/Linker/IRMover.cpp
+++ llvm/lib/Linker/IRMover.cpp
@@ -708,6 +708,25 @@
                              SGV->getThreadLocalMode(), SGV->getAddressSpace());
   }
 
+  if (IsPerformingImport) {
+    // If there's a symver for the imported symbol, import it too.
+    NamedMDNode *Symvers = SGV->getParent()->getNamedMetadata("symvers");
+    if (Symvers) {
+      // FIXME: Use a faster data structure.
+      for (MDNode *Tuple : Symvers->operands()) {
+        StringRef Name =  cast<MDString>(Tuple->getOperand(0))->getString();
+        StringRef Alias = cast<MDString>(Tuple->getOperand(1))->getString();
+        if (Name == SGV->getName()) {
+          SmallString<256> S(".symver ");
+          S += Name;
+          S += ", ";
+          S += Alias;
+          DstM.appendModuleInlineAsm(S);
+        }
+      }
+    }
+  }
+
   if (ForDefinition)
     NewGV->setLinkage(SGV->getLinkage());
   else if (SGV->hasExternalWeakLinkage())
Index: llvm/lib/Transforms/IPO/ThinLTOBitcodeWriter.cpp
===================================================================
--- llvm/lib/Transforms/IPO/ThinLTOBitcodeWriter.cpp
+++ llvm/lib/Transforms/IPO/ThinLTOBitcodeWriter.cpp
@@ -475,6 +475,24 @@
 
   // Write it out as an unsplit ThinLTO module.
 
+  // Add symver metadata.
+  // FIXME: Move to a helper function, since splitAndWriteThinLTOBitcode() has the same code?
+  SmallVector<MDNode *, 8> Symvers;
+  ModuleSymbolTable::CollectAsmSymvers(M, [&](StringRef Name, StringRef Alias) {
+    Function *F = M.getFunction(Name);
+    if (!F || F->use_empty())
+      return;
+    auto &Ctx = M.getContext();
+    Symvers.push_back(MDTuple::get(
+        Ctx, {MDString::get(Ctx, Name), MDString::get(Ctx, Alias)}));
+  });
+  if (!Symvers.empty()) {
+    llvm::errs () << "writing symvers metadata\n";
+    NamedMDNode *NMD = M.getOrInsertNamedMetadata("symvers");
+    for (auto MD : Symvers)
+      NMD->addOperand(MD);
+  }
+
   // Save the module hash produced for the full bitcode, which will
   // be used in the backends, and use that in the minimized bitcode
   // produced for the full link.
Index: llvm/test/ThinLTO/X86/Inputs/import-symver-foo.ll
===================================================================
--- /dev/null
+++ llvm/test/ThinLTO/X86/Inputs/import-symver-foo.ll
@@ -0,0 +1,12 @@
+target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+module asm ".symver bar, bar@BAR_1.2.3"
+
+declare dso_local i32 @bar()
+
+define dso_local i32 @foo() {
+entry:
+  %call = tail call i32 @bar()
+  ret i32 %call
+}
Index: llvm/test/ThinLTO/X86/import-symver.ll
===================================================================
--- /dev/null
+++ llvm/test/ThinLTO/X86/import-symver.ll
@@ -0,0 +1,21 @@
+; RUN: opt -thinlto-bc %s -o %t1.bc
+; RUN: opt -thinlto-bc %p/Inputs/import-symver-foo.ll -o %t2.bc
+; RUN: llvm-lto -thinlto-action=thinlink %t1.bc %t2.bc -o %t3.index.bc
+
+; RUN: llvm-lto -thinlto-action=import -exported-symbol=main %t1.bc -thinlto-index=%t3.index.bc
+; RUN: llvm-dis %t1.bc.thinlto.imported.bc -o - | FileCheck %s
+
+; When @bar gets imported, the symver must be imported too.
+; CHECK: module asm ".symver bar, bar@BAR_1.2.3"
+; CHECK: declare dso_local i32 @bar()
+
+target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+declare dso_local i32 @foo()
+
+define dso_local i32 @main() {
+entry:
+  %call = tail call i32 @foo()
+  ret i32 %call
+}
Index: llvm/test/Transforms/ThinLTOBitcodeWriter/symver.ll
===================================================================
--- llvm/test/Transforms/ThinLTOBitcodeWriter/symver.ll
+++ llvm/test/Transforms/ThinLTOBitcodeWriter/symver.ll
@@ -1,6 +1,8 @@
 ; RUN: opt -thinlto-bc -thinlto-split-lto-unit -o %t %s
 ; RUN: llvm-modextract -n 1 -o - %t | llvm-dis | FileCheck %s
 
+; RUN: opt -thinlto-bc %s | llvm-dis | FileCheck %s
+
 ; The target assembly parser is required to parse the symver directives
 ; REQUIRES: x86-registered-target