diff --git a/clang/lib/Lex/Preprocessor.cpp b/clang/lib/Lex/Preprocessor.cpp
index 7303937..096a610 100644
--- a/clang/lib/Lex/Preprocessor.cpp
+++ b/clang/lib/Lex/Preprocessor.cpp
@@ -712,9 +712,12 @@
   // Note that we do not treat 'import' as a contextual
   // keyword when we're in a caching lexer, because caching lexers only get
   // used in contexts where import declarations are disallowed.
-  if (LastTokenWasAt && II.isModulesImport() && !InMacroArgs && 
-      !DisableMacroExpansion &&
-      (getLangOpts().Modules || getLangOpts().DebuggerSupport) && 
+  //
+  // Likewise if this is the C++ Modules TS import keyword.
+  if (((LastTokenWasAt && II.isModulesImport()) ||
+       Identifier.is(tok::kw_import)) &&
+      !InMacroArgs && !DisableMacroExpansion &&
+      (getLangOpts().Modules || getLangOpts().DebuggerSupport) &&
       CurLexerKind != CLK_CachingLexer) {
     ModuleImportLoc = Identifier.getLocation();
     ModuleImportPath.clear();
@@ -782,7 +785,8 @@
   }
   
   // If we're expecting a '.' or a ';', and we got a '.', then wait until we
-  // see the next identifier.
+  // see the next identifier. (We can also see a '[[' that begins an
+  // attribute-specifier-seq here under the C++ Modules TS.)
   if (!ModuleImportExpectsIdentifier && Result.getKind() == tok::period) {
     ModuleImportExpectsIdentifier = true;
     CurLexerKind = CLK_LexAfterModuleImport;