Revert "[ParseableInterface] Fix failing to build a module when the importing file has errors."

Author: beccadax

lib/Frontend/ParseableInterfaceSupport.cpp

@@ -452,7 +452,7 @@ bool ParseableInterfaceModuleLoader::buildSwiftModuleFromSwiftInterface(
       return;
     }
 
-    SubError = SubInstance.getDiags().hadAnyError();
+    SubError = Diags.hadAnyError();
   });
   return !RunSuccess || SubError;
 }

test/ParseableInterface/ModuleCache/module-cache-errors-in-importing-file.swift

@@ -259,12 +259,6 @@ static llvm::cl::opt<std::string>
 ModuleCachePath("module-cache-path", llvm::cl::desc("Clang module cache path"),
                 llvm::cl::cat(Category));
 
-static llvm::cl::opt<bool>
-EnableParseableModuleInterface("enable-parseable-module-interface",
-           llvm::cl::desc("Enable loading .swiftinterface files when available"),
-           llvm::cl::cat(Category),
-           llvm::cl::init(true));
-
 static llvm::cl::opt<std::string>
 PCHOutputDir("pch-output-dir",
              llvm::cl::desc("place autogenerated PCH files in this directory"),
@@ -3131,8 +3125,6 @@ int main(int argc, char *argv[]) {
         InitInvok.getLangOptions().EffectiveLanguageVersion = actual.getValue();
     }
   }
-  InitInvok.getFrontendOptions().EnableParseableModuleInterface =
-    options::EnableParseableModuleInterface;
   InitInvok.getClangImporterOptions().ModuleCachePath =
     options::ModuleCachePath;
   InitInvok.getClangImporterOptions().PrecompiledHeaderOutputDir =