diff --git a/clang-tools-extra/pseudo/include/clang-pseudo/Token.h b/clang-tools-extra/pseudo/include/clang-pseudo/Token.h
--- a/clang-tools-extra/pseudo/include/clang-pseudo/Token.h
+++ b/clang-tools-extra/pseudo/include/clang-pseudo/Token.h
@@ -29,6 +29,7 @@
 #define CLANG_PSEUDO_TOKEN_H
 
 #include "clang/Basic/LLVM.h"
+#include "clang/Basic/LangStandard.h"
 #include "clang/Basic/TokenKinds.h"
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/Support/raw_ostream.h"
@@ -193,6 +194,10 @@
   /// The text() of such tokens will contain the raw trigrah.
   NeedsCleaning = 1 << 1,
 };
+/// A generic lang options suitable for lexing/parsing a langage.
+clang::LangOptions genericLangOpts(
+    clang::Language = clang::Language::CXX,
+    clang::LangStandard::Kind = clang::LangStandard::lang_unspecified);
 
 /// Derives a token stream by decoding escapes, interpreting raw_identifiers and
 /// splitting the greatergreater token.
diff --git a/clang-tools-extra/pseudo/lib/Token.cpp b/clang-tools-extra/pseudo/lib/Token.cpp
--- a/clang-tools-extra/pseudo/lib/Token.cpp
+++ b/clang-tools-extra/pseudo/lib/Token.cpp
@@ -7,6 +7,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "clang-pseudo/Token.h"
+#include "clang/Basic/LangOptions.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/Support/Format.h"
 #include "llvm/Support/FormatVariadic.h"
@@ -92,6 +93,28 @@
     OS << '\n';
 }
 
+clang::LangOptions genericLangOpts(clang::Language Lang,
+                                   clang::LangStandard::Kind Standard) {
+  clang::LangOptions Opts;
+  std::vector<std::string> UnusedIncludes;
+  LangOptions::setLangDefaults(Opts, Lang, llvm::Triple(), UnusedIncludes,
+                               Standard);
+
+  // Some options are "on by default", but e.g. at the driver level.
+  if (Opts.CPlusPlus)
+    Opts.CXXOperatorNames = true;
+  if (Opts.CPlusPlus20)
+    Opts.Coroutines = true;
+
+  // Some options are off by default, but define keywords we want to tolerate.
+  if (Opts.CPlusPlus)
+    Opts.MicrosoftExt = true;  // kw__try, kw__finally
+  Opts.DeclSpecKeyword = true; // __declspec
+  Opts.WChar = true;
+
+  return Opts;
+}
+
 TokenStream stripComments(const TokenStream &Input) {
   TokenStream Out;
   for (const Token &T : Input.tokens()) {
diff --git a/clang-tools-extra/pseudo/test/glr.cpp b/clang-tools-extra/pseudo/test/glr.cpp
--- a/clang-tools-extra/pseudo/test/glr.cpp
+++ b/clang-tools-extra/pseudo/test/glr.cpp
@@ -21,3 +21,15 @@
 // CHECK-NEXT:   │ └─ptr-declarator~IDENTIFIER := tok[7]
 // CHECK-NEXT:   └─; := tok[8]
 }
+
+bool operator<();
+// CHECK:      declaration~simple-declaration := decl-specifier-seq init-declarator-list ;
+// CHECK-NEXT: ├─decl-specifier-seq~BOOL
+// CHECK-NEXT: ├─init-declarator-list~noptr-declarator := noptr-declarator parameters-and-qualifiers
+// CHECK-NEXT: │ ├─noptr-declarator~operator-function-id := OPERATOR operator-name
+// CHECK-NEXT: │ │ ├─OPERATOR
+// CHECK-NEXT: │ │ └─operator-name~<
+// CHECK-NEXT: │ └─parameters-and-qualifiers := ( )
+// CHECK-NEXT: │   ├─(
+// CHECK-NEXT: │   └─)
+// CHECK-NEXT: └─;
diff --git a/clang-tools-extra/pseudo/tool/ClangPseudo.cpp b/clang-tools-extra/pseudo/tool/ClangPseudo.cpp
--- a/clang-tools-extra/pseudo/tool/ClangPseudo.cpp
+++ b/clang-tools-extra/pseudo/tool/ClangPseudo.cpp
@@ -53,14 +53,12 @@
 int main(int argc, char *argv[]) {
   llvm::cl::ParseCommandLineOptions(argc, argv, "");
 
-  clang::LangOptions LangOpts; // FIXME: use real options.
-  LangOpts.CPlusPlus = 1;
+  clang::LangOptions LangOpts = clang::pseudo::genericLangOpts();
   llvm::Optional<clang::pseudo::TokenStream> RawStream;
   llvm::Optional<clang::pseudo::DirectiveTree> DirectiveStructure;
   llvm::Optional<clang::pseudo::TokenStream> ParseableStream;
   if (Source.getNumOccurrences()) {
     std::string Text = readOrDie(Source);
-    clang::LangOptions LangOpts; // FIXME: use real options.
     RawStream = clang::pseudo::lex(Text, LangOpts);
     DirectiveStructure = clang::pseudo::DirectiveTree::parse(*RawStream);
     clang::pseudo::chooseConditionalBranches(*DirectiveStructure, *RawStream);