[clang] [clang-repl] Handle mllvm args for clang-repl before calling executeAction (PR #197133)
Anutosh Bhat via cfe-commits
cfe-commits at lists.llvm.org
Wed Oct 7 20:46:15 PDT 2026
https://github.com/anutosh491 updated https://github.com/llvm/llvm-project/pull/197133
>From 2d4c29cc72b3a330ba2e789c07b107c1ad3bc041 Mon Sep 17 00:00:00 2001
From: anutosh491 <andersonbhat491 at gmail.com>
Date: Thu, 8 Oct 2026 09:15:51 +0530
Subject: [PATCH] Handle mllvm args for clang-repl before calling
executeAction- #197133
---
.../include/clang/Frontend/CompilerInstance.h | 5 ++++
.../clang/Interpreter/IncrementalExecutor.h | 4 ++++
clang/lib/Frontend/CompilerInstance.cpp | 14 +++++++++++
.../ExecuteCompilerInvocation.cpp | 16 +------------
clang/lib/Interpreter/IncrementalExecutor.cpp | 2 +-
clang/lib/Interpreter/Interpreter.cpp | 7 ++++++
clang/lib/Interpreter/Wasm.cpp | 21 ++++++++++++++++-
clang/lib/Interpreter/Wasm.h | 5 +++-
clang/unittests/Interpreter/CMakeLists.txt | 1 +
.../unittests/Interpreter/InterpreterTest.cpp | 23 +++++++++++++++++++
.../Interpreter/InterpreterTestFixture.h | 12 +++++++++-
11 files changed, 91 insertions(+), 19 deletions(-)
diff --git a/clang/include/clang/Frontend/CompilerInstance.h b/clang/include/clang/Frontend/CompilerInstance.h
index 977180a8dc3aa..b87dd037480d6 100644
--- a/clang/include/clang/Frontend/CompilerInstance.h
+++ b/clang/include/clang/Frontend/CompilerInstance.h
@@ -264,6 +264,11 @@ class CompilerInstance : public ModuleLoader {
/// Load the list of plugins requested in the \c FrontendOptions.
void LoadRequestedPlugins();
+ /// Parse and apply LLVM command line arguments from FrontendOptions.
+ /// This processes the LLVMArgs option that comes from -mllvm flags.
+ /// This should be called after plugins are loaded and before ExecuteAction.
+ void parseLLVMArgs();
+
/// @}
/// @name Compiler Invocation and Options
/// @{
diff --git a/clang/include/clang/Interpreter/IncrementalExecutor.h b/clang/include/clang/Interpreter/IncrementalExecutor.h
index 913da9230a947..f1a68c0288d00 100644
--- a/clang/include/clang/Interpreter/IncrementalExecutor.h
+++ b/clang/include/clang/Interpreter/IncrementalExecutor.h
@@ -52,6 +52,10 @@ class IncrementalExecutorBuilder {
std::optional<llvm::CodeModel::Model> CM = std::nullopt;
/// An optional external IncrementalExecutor
std::unique_ptr<IncrementalExecutor> IE;
+ /// mllvm args from the frontend; on wasm these are re-applied after each
+ /// lldMain call because lld resets all cl options for test-isolation
+ /// purposes.
+ std::vector<std::string> LLVMArgs;
/// An optional external orc jit builder
std::unique_ptr<llvm::orc::LLJITBuilder> JITBuilder;
/// A default callback that can be used in the IncrementalCompilerBuilder to
diff --git a/clang/lib/Frontend/CompilerInstance.cpp b/clang/lib/Frontend/CompilerInstance.cpp
index 7048bec2cdceb..b09c9a9f5a5be 100644
--- a/clang/lib/Frontend/CompilerInstance.cpp
+++ b/clang/lib/Frontend/CompilerInstance.cpp
@@ -1135,6 +1135,20 @@ void CompilerInstance::LoadRequestedPlugins() {
}
}
+void CompilerInstance::parseLLVMArgs() {
+ if (!getFrontendOpts().LLVMArgs.empty()) {
+ unsigned NumArgs = getFrontendOpts().LLVMArgs.size();
+ auto Args = std::make_unique<const char *[]>(NumArgs + 2);
+ Args[0] = "clang (LLVM option parsing)";
+ for (unsigned i = 0; i != NumArgs; ++i)
+ Args[i + 1] = getFrontendOpts().LLVMArgs[i].c_str();
+ Args[NumArgs + 1] = nullptr;
+ llvm::cl::ParseCommandLineOptions(NumArgs + 1, Args.get(), /*Overview=*/"",
+ /*Errs=*/nullptr,
+ /*VFS=*/&getVirtualFileSystem());
+ }
+}
+
/// Determine the appropriate source input kind based on language
/// options.
static Language getLanguageFromOptions(const LangOptions &LangOpts) {
diff --git a/clang/lib/FrontendTool/ExecuteCompilerInvocation.cpp b/clang/lib/FrontendTool/ExecuteCompilerInvocation.cpp
index e872f0823f23e..24e699b42ca7f 100644
--- a/clang/lib/FrontendTool/ExecuteCompilerInvocation.cpp
+++ b/clang/lib/FrontendTool/ExecuteCompilerInvocation.cpp
@@ -253,21 +253,7 @@ bool ExecuteCompilerInvocation(CompilerInstance *Clang) {
Clang->LoadRequestedPlugins();
- // Honor -mllvm.
- //
- // FIXME: Remove this, one day.
- // This should happen AFTER plugins have been loaded!
- if (!Clang->getFrontendOpts().LLVMArgs.empty()) {
- unsigned NumArgs = Clang->getFrontendOpts().LLVMArgs.size();
- auto Args = std::make_unique<const char*[]>(NumArgs + 2);
- Args[0] = "clang (LLVM option parsing)";
- for (unsigned i = 0; i != NumArgs; ++i)
- Args[i + 1] = Clang->getFrontendOpts().LLVMArgs[i].c_str();
- Args[NumArgs + 1] = nullptr;
- llvm::cl::ParseCommandLineOptions(NumArgs + 1, Args.get(), /*Overview=*/"",
- /*Errs=*/nullptr,
- /*VFS=*/&Clang->getVirtualFileSystem());
- }
+ Clang->parseLLVMArgs();
#if CLANG_ENABLE_STATIC_ANALYZER
// These should happen AFTER plugins have been loaded!
diff --git a/clang/lib/Interpreter/IncrementalExecutor.cpp b/clang/lib/Interpreter/IncrementalExecutor.cpp
index 5d01ba4774269..101120626f766 100644
--- a/clang/lib/Interpreter/IncrementalExecutor.cpp
+++ b/clang/lib/Interpreter/IncrementalExecutor.cpp
@@ -429,7 +429,7 @@ IncrementalExecutorBuilder::create(llvm::orc::ThreadSafeContext &TSC,
llvm::Error Err = llvm::Error::success();
std::unique_ptr<IncrementalExecutor> Executor;
#ifdef __EMSCRIPTEN__
- Executor = std::make_unique<WasmIncrementalExecutor>(Err);
+ Executor = std::make_unique<WasmIncrementalExecutor>(Err, LLVMArgs);
#else
Executor = std::make_unique<OrcIncrementalExecutor>(TSC, *JITBuilder, Err);
#endif
diff --git a/clang/lib/Interpreter/Interpreter.cpp b/clang/lib/Interpreter/Interpreter.cpp
index 40fbc83db9107..85cefa1270049 100644
--- a/clang/lib/Interpreter/Interpreter.cpp
+++ b/clang/lib/Interpreter/Interpreter.cpp
@@ -352,6 +352,9 @@ Interpreter::Interpreter(std::unique_ptr<CompilerInstance> Instance,
auto LLVMCtx = std::make_unique<llvm::LLVMContext>();
TSCtx = std::make_unique<llvm::orc::ThreadSafeContext>(std::move(LLVMCtx));
+ // Honor -mllvm options
+ CI->parseLLVMArgs();
+
Act = TSCtx->withContextDo([&](llvm::LLVMContext *Ctx) {
return std::make_unique<IncrementalAction>(*CI, *Ctx, ErrOut, *this,
std::move(Consumer));
@@ -608,6 +611,10 @@ llvm::Error Interpreter::CreateExecutor() {
if (!IncrExecutorBuilder)
IncrExecutorBuilder = std::make_unique<IncrementalExecutorBuilder>();
+ // Propagate mllvm args so the wasm executor can restore them after each
+ // lldMain invocation (which resets all cl options for test isolation).
+ IncrExecutorBuilder->LLVMArgs = CI->getFrontendOpts().LLVMArgs;
+
auto ExecutorOrErr = IncrExecutorBuilder->create(*TSCtx, CI->getTarget());
if (ExecutorOrErr)
IncrExecutor = std::move(*ExecutorOrErr);
diff --git a/clang/lib/Interpreter/Wasm.cpp b/clang/lib/Interpreter/Wasm.cpp
index 573c8910d3a41..017b049fb470c 100644
--- a/clang/lib/Interpreter/Wasm.cpp
+++ b/clang/lib/Interpreter/Wasm.cpp
@@ -12,6 +12,7 @@
#include "Wasm.h"
+#include "llvm/Support/CommandLine.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/Path.h"
#include <llvm/IR/LegacyPassManager.h>
@@ -61,7 +62,9 @@ bool link(llvm::ArrayRef<const char *> args, llvm::raw_ostream &stdoutOS,
namespace clang {
-WasmIncrementalExecutor::WasmIncrementalExecutor(llvm::Error &Err) {
+WasmIncrementalExecutor::WasmIncrementalExecutor(
+ llvm::Error &Err, std::vector<std::string> LLVMArgs)
+ : StoredLLVMArgs(std::move(LLVMArgs)) {
llvm::ErrorAsOutParameter EAO(&Err);
if (Err)
@@ -142,6 +145,22 @@ llvm::Error WasmIncrementalExecutor::addModule(PartialTranslationUnit &PTU) {
if (!Result.canRunAgain)
lld::exitLld(Result.retCode);
+ // lld::wasm::linkerMain calls cl::ResetAllOptionOccurrences() which wipes
+ // all global LLVM cl options, including mllvm flags set by the frontend
+ // (e.g. -wasm-enable-eh, -wasm-enable-sjlj). Re-apply them so the next
+ // Parse() call's WebAssemblyTargetMachine creation finds the correct state.
+ //
+ // FIXME: Remove this once library command-line options no longer rely on
+ // process-global cl::opt state. See:
+ // https://discourse.llvm.org/t/rfc-declare-library-command-line-options-in-tablegen-one-struct-per-library/91877
+ if (!StoredLLVMArgs.empty()) {
+ std::vector<const char *> ArgPtrs;
+ ArgPtrs.push_back("clang-repl (restoring LLVM options)");
+ for (const std::string &Arg : StoredLLVMArgs)
+ ArgPtrs.push_back(Arg.c_str());
+ llvm::cl::ParseCommandLineOptions(ArgPtrs.size(), ArgPtrs.data());
+ }
+
if (Result.retCode)
return llvm::make_error<llvm::StringError>(
"Failed to link incremental module", llvm::inconvertibleErrorCode());
diff --git a/clang/lib/Interpreter/Wasm.h b/clang/lib/Interpreter/Wasm.h
index bf8777a41eac2..6340393dc6b9b 100644
--- a/clang/lib/Interpreter/Wasm.h
+++ b/clang/lib/Interpreter/Wasm.h
@@ -19,12 +19,14 @@
#include "clang/Interpreter/IncrementalExecutor.h"
#include "llvm/ADT/SmallString.h"
+#include <string>
+#include <vector>
namespace clang {
class WasmIncrementalExecutor : public IncrementalExecutor {
public:
- WasmIncrementalExecutor(llvm::Error &Err);
+ WasmIncrementalExecutor(llvm::Error &Err, std::vector<std::string> LLVMArgs);
~WasmIncrementalExecutor() override;
llvm::Error addModule(PartialTranslationUnit &PTU) override;
@@ -38,6 +40,7 @@ class WasmIncrementalExecutor : public IncrementalExecutor {
private:
llvm::SmallString<256> TempDir;
+ std::vector<std::string> StoredLLVMArgs;
};
} // namespace clang
diff --git a/clang/unittests/Interpreter/CMakeLists.txt b/clang/unittests/Interpreter/CMakeLists.txt
index 6d999104054c3..d18d7819001b1 100644
--- a/clang/unittests/Interpreter/CMakeLists.txt
+++ b/clang/unittests/Interpreter/CMakeLists.txt
@@ -77,6 +77,7 @@ get_target_property(LINKED_LIBS ClangReplInterpreterTests LINK_LIBRARIES)
list(REMOVE_ITEM LINKED_LIBS LLVMSupport)
set_target_properties(ClangReplInterpreterTests PROPERTIES LINK_LIBRARIES "${LINKED_LIBS}")
target_link_options(ClangReplInterpreterTests
+ PUBLIC "SHELL: -fwasm-exceptions"
PUBLIC "SHELL: -s MAIN_MODULE=1"
PUBLIC "SHELL: -s ALLOW_MEMORY_GROWTH=1"
PUBLIC "SHELL: -s STACK_SIZE=32mb"
diff --git a/clang/unittests/Interpreter/InterpreterTest.cpp b/clang/unittests/Interpreter/InterpreterTest.cpp
index a0ed7e671ddbe..17cc6fc9b6ca8 100644
--- a/clang/unittests/Interpreter/InterpreterTest.cpp
+++ b/clang/unittests/Interpreter/InterpreterTest.cpp
@@ -174,6 +174,9 @@ TEST_F(InterpreterTest, TranslationUnitRedeclChainAcrossManyPTUs) {
}
TEST_F(InterpreterTest, UndoLeavesDeclsInTranslationUnitChain) {
+#ifdef __EMSCRIPTEN__
+ GTEST_SKIP() << "Undo is not supported for Emscripten builds";
+#endif
std::unique_ptr<Interpreter> Interp = createInterpreter();
cantFail(Interp->Parse("struct Kept {};"));
@@ -520,6 +523,11 @@ TEST_F(InterpreterTest, ValueSetRawBitsCopiesByteCount) {
// Earlier the move ctor called Release() on the just-moved-into storage,
// double-releasing on the next read.
TEST_F(InterpreterTest, ValueMoveSemantics) {
+ // FIXME: Emscripten cannot resolve MoveT's destructor symbol
+ // `_ZN5MoveTD2Ev` from the incrementally loaded Wasm side module.
+#ifdef __EMSCRIPTEN__
+ GTEST_SKIP() << "Unresolved destructor symbol: _ZN5MoveTD2Ev";
+#endif
std::vector<const char *> Args = {"-fno-sized-deallocation"};
std::unique_ptr<Interpreter> Interp = createInterpreter(Args);
@@ -588,4 +596,19 @@ 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++23", "-v", "-fwasm-exceptions", "-mllvm",
+ "-wasm-enable-sjlj"};
+
+ std::unique_ptr<Interpreter> Interp = createInterpreter(ExtraArgs);
+
+ llvm::cantFail(
+ Interp->ParseAndExecute("try { throw 1; } catch (...) { 0; }"));
+}
+
} // end anonymous namespace
diff --git a/clang/unittests/Interpreter/InterpreterTestFixture.h b/clang/unittests/Interpreter/InterpreterTestFixture.h
index b088fa4a5f896..c4a30dd06220c 100644
--- a/clang/unittests/Interpreter/InterpreterTestFixture.h
+++ b/clang/unittests/Interpreter/InterpreterTestFixture.h
@@ -55,7 +55,17 @@ class InterpreterTestBase : public ::testing::Test {
llvm::InitializeNativeTargetAsmPrinter();
}
- static void TearDownTestSuite() { llvm::llvm_shutdown(); }
+ static void TearDownTestSuite() {
+ // llvm_shutdown() cleans up JIT (LLJIT/ORC) state between test suites.
+ // On Emscripten, WasmIncrementalExecutor is used instead of LLJIT, so
+ // there is no JIT state to tear down. Calling llvm_shutdown() here would
+ // destroy the ManagedStatic<CommandLineParser> global, permanently
+ // deregistering all cl::opt options (wasm-enable-eh, etc.) since their
+ // constructors already ran and will not fire again after the reset.
+#ifndef __EMSCRIPTEN__
+ llvm::llvm_shutdown();
+#endif
+ }
};
} // namespace clang
More information about the cfe-commits
mailing list