diff --git a/include/swift/Basic/LangOptions.h b/include/swift/Basic/LangOptions.h
index 979f8d2cf3166..a4e4ccefd6474 100644
--- a/include/swift/Basic/LangOptions.h
+++ b/include/swift/Basic/LangOptions.h
@@ -828,7 +828,7 @@ namespace swift {
     bool DisableOverlayModules = false;
 
     /// When set, import SPI_AVAILABLE symbols with Swift SPI attribtues.
-    bool EnableClangSPI = false;
+    bool EnableClangSPI = true;
 
     /// When set, don't enforce warnings with -Werror.
     bool DebuggerSupport = false;
diff --git a/include/swift/Option/FrontendOptions.td b/include/swift/Option/FrontendOptions.td
index 919ee4413d0ae..98a2c8280600b 100644
--- a/include/swift/Option/FrontendOptions.td
+++ b/include/swift/Option/FrontendOptions.td
@@ -142,9 +142,9 @@ def disable_testable_attr_requires_testable_module :
   Flag<["-"], "disable-testable-attr-requires-testable-module">,
   HelpText<"Disable checking of @testable">;
 
-def enable_clang_spi :
-  Flag<["-"], "enable-clang-spi">,
-  HelpText<"Import Clang SPIs as Swift SPIs">;
+def disable_clang_spi :
+  Flag<["-"], "disable-clang-spi">,
+  HelpText<"Don't import Clang SPIs as Swift SPIs">;
 
 def enable_target_os_checking :
   Flag<["-"], "enable-target-os-checking">,
diff --git a/lib/ClangImporter/ImportDecl.cpp b/lib/ClangImporter/ImportDecl.cpp
index 0e4ac22ab00c6..0e9d3843263ad 100644
--- a/lib/ClangImporter/ImportDecl.cpp
+++ b/lib/ClangImporter/ImportDecl.cpp
@@ -9069,7 +9069,7 @@ void ClangImporter::Implementation::importAttributes(
                                           obsoleted,
                                           /*ObsoletedRange=*/SourceRange(),
                                           PlatformAgnostic, /*Implicit=*/false,
-                                          IsSPI);
+                                          EnableClangSPI && IsSPI);
 
       MappedDecl->getAttrs().add(AvAttr);
     }
diff --git a/lib/Frontend/CompilerInvocation.cpp b/lib/Frontend/CompilerInvocation.cpp
index c133d42bb615e..257bac3674c91 100644
--- a/lib/Frontend/CompilerInvocation.cpp
+++ b/lib/Frontend/CompilerInvocation.cpp
@@ -1194,7 +1194,7 @@ static bool ParseClangImporterArgs(ClangImporterOptions &Opts,
 
   Opts.DisableOverlayModules |= Args.hasArg(OPT_emit_imported_modules);
 
-  Opts.EnableClangSPI |= Args.hasArg(OPT_enable_clang_spi);
+  Opts.EnableClangSPI = !Args.hasArg(OPT_disable_clang_spi);
 
   Opts.ExtraArgsOnly |= Args.hasArg(OPT_extra_clang_options_only);