diff --git a/src/rustllvm/PassWrapper.cpp b/src/rustllvm/PassWrapper.cpp
index b2f1229891d..06d1301d700 100644
--- a/src/rustllvm/PassWrapper.cpp
+++ b/src/rustllvm/PassWrapper.cpp
@@ -836,6 +836,10 @@ struct LLVMRustThinLTOData {
   StringMap<FunctionImporter::ImportMapTy> ImportLists;
   StringMap<FunctionImporter::ExportSetTy> ExportLists;
   StringMap<GVSummaryMapTy> ModuleToDefinedGVSummaries;
+
+#if LLVM_VERSION_GE(7, 0)
+  LLVMRustThinLTOData() : Index(/* isPerformingAnalysis = */ false) {}
+#endif
 };
 
 // Just an argument to the `LLVMRustCreateThinLTOData` function below.
@@ -918,7 +922,14 @@ LLVMRustCreateThinLTOData(LLVMRustThinLTOModule *modules,
   //
   // This is copied from `lib/LTO/ThinLTOCodeGenerator.cpp`
 #if LLVM_VERSION_GE(5, 0)
+#if LLVM_VERSION_GE(7, 0)
+  auto deadIsPrevailing = [&](GlobalValue::GUID G) {
+    return PrevailingType::Unknown;
+  };
+  computeDeadSymbols(Ret->Index, Ret->GUIDPreservedSymbols, deadIsPrevailing);
+#else
   computeDeadSymbols(Ret->Index, Ret->GUIDPreservedSymbols);
+#endif
   ComputeCrossModuleImport(
     Ret->Index,
     Ret->ModuleToDefinedGVSummaries,