diff --git a/clang/include/clang/Lex/ModuleLoader.h b/clang/include/clang/Lex/ModuleLoader.h
--- a/clang/include/clang/Lex/ModuleLoader.h
+++ b/clang/include/clang/Lex/ModuleLoader.h
@@ -45,9 +45,6 @@
 
     // The module exists but cannot be imported due to a configuration mismatch.
     ConfigMismatch,
-
-    // We failed to load the module, but we shouldn't cache the failure.
-    OtherUncachedFailure,
   };
   llvm::PointerIntPair<Module *, 2, LoadResultKind> Storage;
 
diff --git a/clang/lib/Frontend/CompilerInstance.cpp b/clang/lib/Frontend/CompilerInstance.cpp
--- a/clang/lib/Frontend/CompilerInstance.cpp
+++ b/clang/lib/Frontend/CompilerInstance.cpp
@@ -1684,8 +1684,7 @@
     getDiagnostics().Report(ModuleNameLoc, diag::err_module_not_found)
         << ModuleName << SourceRange(ImportLoc, ModuleNameLoc);
     ModuleBuildFailed = true;
-    // FIXME: Why is this not cached?
-    return ModuleLoadResult::OtherUncachedFailure;
+    return nullptr;
   }
   if (ModuleFilename.empty()) {
     if (M && M->HasIncompatibleModuleFile) {
@@ -1697,8 +1696,7 @@
     getDiagnostics().Report(ModuleNameLoc, diag::err_module_build_disabled)
         << ModuleName;
     ModuleBuildFailed = true;
-    // FIXME: Why is this not cached?
-    return ModuleLoadResult::OtherUncachedFailure;
+    return nullptr;
   }
 
   // Create an ASTReader on demand.
@@ -1809,8 +1807,7 @@
     getDiagnostics().Report(ModuleNameLoc, diag::err_module_cycle)
         << ModuleName << CyclePath;
     // FIXME: Should this set ModuleBuildFailed = true?
-    // FIXME: Why is this not cached?
-    return ModuleLoadResult::OtherUncachedFailure;
+    return nullptr;
   }
 
   // Check whether we have already attempted to build this module (but
@@ -1820,8 +1817,7 @@
     getDiagnostics().Report(ModuleNameLoc, diag::err_module_not_built)
         << ModuleName << SourceRange(ImportLoc, ModuleNameLoc);
     ModuleBuildFailed = true;
-    // FIXME: Why is this not cached?
-    return ModuleLoadResult::OtherUncachedFailure;
+    return nullptr;
   }
 
   // Try to compile and then read the AST.
@@ -1832,8 +1828,7 @@
     if (getPreprocessorOpts().FailedModules)
       getPreprocessorOpts().FailedModules->addFailed(ModuleName);
     ModuleBuildFailed = true;
-    // FIXME: Why is this not cached?
-    return ModuleLoadResult::OtherUncachedFailure;
+    return nullptr;
   }
 
   // Okay, we've rebuilt and now loaded the module.