Index: flang/tools/bbc/bbc.cpp
===================================================================
--- flang/tools/bbc/bbc.cpp
+++ flang/tools/bbc/bbc.cpp
@@ -185,6 +185,10 @@
                                     llvm::cl::desc("Lower to high level FIR"),
                                     llvm::cl::init(false));
 
+static llvm::cl::opt<bool> enableCUDA("fcuda",
+                                      llvm::cl::desc("enable CUDA Fortran"),
+                                      llvm::cl::init(false));
+
 #define FLANG_EXCLUDE_CODEGEN
 #include "flang/Tools/CLOptions.inc"
 
@@ -401,6 +405,12 @@
     options.predefinitions.emplace_back("_OPENACC", "202211");
   }
 
+  // enable parsing of CUDA Fortran
+  if (enableCUDA) {
+    options.features.Enable(Fortran::common::LanguageFeature::CUDA);
+    options.predefinitions.emplace_back("_CUDA", "1");
+  }
+
   Fortran::common::IntrinsicTypeDefaultKinds defaultKinds;
   Fortran::parser::AllSources allSources;
   Fortran::parser::AllCookedSources allCookedSources(allSources);