[clang-repl] Handle frontend options for clang-repl before calling executeAction

clang/lib/Interpreter/Interpreter.cpp

@@ -143,6 +143,41 @@ CreateCI(const llvm::opt::ArgStringList &Argv) {
   return std::move(Clang);
 }
 
+static llvm::Error HandleFrontendOptions(const CompilerInstance &CI) {
+  const auto &FrontendOpts = CI.getFrontendOpts();
+
+  // FIXME: Temporary duplication to honor -mllvm in clang-repl.
+  // clang/flang handle -mllvm in their tool-side ExecuteCompilerInvocation
+  // paths. clang-repl currently lacks that step, so we minimally parse
+  // FrontendOpts.LLVMArgs here to ensure -mllvm options take effect.
+  // Follow-up work:
+  // Move this -mllvm handling into a shared, driver/tool-level facility
+  // used by clang, clang-repl, flang, etc., and remove this library-side
+  // duplication.
+
+  if (!FrontendOpts.LLVMArgs.empty()) {
+    unsigned NumArgs = FrontendOpts.LLVMArgs.size();
+    auto Args = std::make_unique<const char *[]>(NumArgs + 2);
+    Args[0] = "clang-repl (LLVM option parsing)";
+    for (unsigned i = 0; i != NumArgs; ++i) {
+      Args[i + 1] = FrontendOpts.LLVMArgs[i].c_str();
+      if (Args[i + 1][0] == '-') {
+        auto *option = static_cast<llvm::cl::opt<bool> *>(
+            llvm::cl::getRegisteredOptions()[Args[i + 1] + 1]);
+        if (option) {
+          option->setInitialValue(true);
+        } else {
+          llvm::errs() << "Unknown LLVM option: " << Args[i + 1] << "\n";
+        }
+      }
+    }
+    Args[NumArgs + 1] = nullptr;
+    llvm::cl::ParseCommandLineOptions(NumArgs + 1, Args.get());
+  }
+
+  return llvm::Error::success();
+}
+
 } // anonymous namespace
 
 namespace clang {
@@ -418,8 +453,6 @@ Interpreter::getOrcRuntimePath(const driver::ToolChain &TC) {
 
 llvm::Expected<std::unique_ptr<Interpreter>>
 Interpreter::create(std::unique_ptr<CompilerInstance> CI, JITConfig Config) {
-  llvm::Error Err = llvm::Error::success();
-
   std::unique_ptr<llvm::orc::LLJITBuilder> JB;
 
   if (Config.IsOutOfProcess) {
@@ -450,6 +483,11 @@ Interpreter::create(std::unique_ptr<CompilerInstance> CI, JITConfig Config) {
     }
   }
 
+  llvm::Error Err = HandleFrontendOptions(*CI);
+  if (Err) {
+    return std::move(Err);
+  }
+
   auto Interp = std::unique_ptr<Interpreter>(new Interpreter(
       std::move(CI), Err, std::move(JB), /*Consumer=*/nullptr, Config));
   if (auto E = std::move(Err))

clang/unittests/Interpreter/CMakeLists.txt

@@ -80,6 +80,7 @@ target_link_options(ClangReplInterpreterTests
   PUBLIC "SHELL: -s ALLOW_MEMORY_GROWTH=1"
   PUBLIC "SHELL: -s STACK_SIZE=32mb"
   PUBLIC "SHELL: -s INITIAL_MEMORY=128mb"
+  PUBLIC "SHELL: -s NO_DISABLE_EXCEPTION_CATCHING"
   PUBLIC "SHELL: --emrun"
   PUBLIC "SHELL: -Wl,--export=__clang_Interpreter_SetValueWithAlloc"
   PUBLIC "SHELL: -Wl,--export=__clang_Interpreter_SetValueNoAlloc"

clang/unittests/Interpreter/InterpreterTest.cpp

@@ -443,4 +443,21 @@ TEST_F(InterpreterTest, TranslationUnit_CanonicalDecl) {
             sema.getASTContext().getTranslationUnitDecl()->getCanonicalDecl());
 }
 
+TEST_F(InterpreterTest, EmscriptenExceptionHandling) {
+#ifndef __EMSCRIPTEN__
+  GTEST_SKIP() << "This test only applies to Emscripten builds.";
+#endif
+
+  using Args = std::vector<const char *>;
+  Args ExtraArgs = {"-std=c++20",   "-v",
+                    "-fexceptions", "-fcxx-exceptions",
+                    "-mllvm",       "-enable-emscripten-cxx-exceptions",
+                    "-mllvm",       "-enable-emscripten-sjlj"};
+
+  std::unique_ptr<Interpreter> Interp = createInterpreter(ExtraArgs);
+
+  llvm::cantFail(
+      Interp->ParseAndExecute("try { throw 1; } catch (...) { 0; }"));
+}
+
 } // end anonymous namespace