1 files changed, 22 insertions, 13 deletions
diff --git a/llvm/lib/ExecutionEngine/Orc/Core.cpp b/llvm/lib/ExecutionEngine/Orc/Core.cpp
index aa82cf38c45d..e5cb8103919a 100644
--- a/llvm/lib/ExecutionEngine/Orc/Core.cpp
+++ b/llvm/lib/ExecutionEngine/Orc/Core.cpp
@@ -1933,9 +1933,14 @@ Error ExecutionSession::removeJITDylib(JITDylib &JD) {
     JDs.erase(I);
   });
 
-  // Clear the JITDylib.
+  // Clear the JITDylib. Hold on to any error while we clean up the
+  // JITDylib members below.
   auto Err = JD.clear();
 
+  // Notify the platform of the teardown.
+  if (P)
+    Err = joinErrors(std::move(Err), P->teardownJITDylib(JD));
+
   // Set JD to closed state. Clear remaining data structures.
   runSessionLocked([&] {
     assert(JD.State == JITDylib::Closing && "JD should be closing");
@@ -1953,19 +1958,22 @@ Error ExecutionSession::removeJITDylib(JITDylib &JD) {
   return Err;
 }
 
-std::vector<JITDylibSP> JITDylib::getDFSLinkOrder(ArrayRef<JITDylibSP> JDs) {
+Expected<std::vector<JITDylibSP>>
+JITDylib::getDFSLinkOrder(ArrayRef<JITDylibSP> JDs) {
   if (JDs.empty())
-    return {};
+    return std::vector<JITDylibSP>();
 
   auto &ES = JDs.front()->getExecutionSession();
-  return ES.runSessionLocked([&]() {
+  return ES.runSessionLocked([&]() -> Expected<std::vector<JITDylibSP>> {
     DenseSet<JITDylib *> Visited;
     std::vector<JITDylibSP> Result;
 
     for (auto &JD : JDs) {
 
-      assert(JD->State == Open && "JD is defunct");
-
+      if (JD->State != Open)
+        return make_error<StringError>(
+            "Error building link order: " + JD->getName() + " is defunct",
+            inconvertibleErrorCode());
       if (Visited.count(JD.get()))
         continue;
 
@@ -1990,18 +1998,19 @@ std::vector<JITDylibSP> JITDylib::getDFSLinkOrder(ArrayRef<JITDylibSP> JDs) {
   });
 }
 
-std::vector<JITDylibSP>
+Expected<std::vector<JITDylibSP>>
 JITDylib::getReverseDFSLinkOrder(ArrayRef<JITDylibSP> JDs) {
-  auto Tmp = getDFSLinkOrder(JDs);
-  std::reverse(Tmp.begin(), Tmp.end());
-  return Tmp;
+  auto Result = getDFSLinkOrder(JDs);
+  if (Result)
+    std::reverse(Result->begin(), Result->end());
+  return Result;
 }
 
-std::vector<JITDylibSP> JITDylib::getDFSLinkOrder() {
+Expected<std::vector<JITDylibSP>> JITDylib::getDFSLinkOrder() {
   return getDFSLinkOrder({this});
 }
 
-std::vector<JITDylibSP> JITDylib::getReverseDFSLinkOrder() {
+Expected<std::vector<JITDylibSP>> JITDylib::getReverseDFSLinkOrder() {
   return getReverseDFSLinkOrder({this});
 }
 
@@ -2201,7 +2210,7 @@ void ExecutionSession::dump(raw_ostream &OS) {
 
 void ExecutionSession::dispatchOutstandingMUs() {
   LLVM_DEBUG(dbgs() << "Dispatching MaterializationUnits...\n");
-  while (1) {
+  while (true) {
     Optional<std::pair<std::unique_ptr<MaterializationUnit>,
                        std::unique_ptr<MaterializationResponsibility>>>
         JMU;