#include "llvm/Support/Mutex.h"
namespace llvm {
- /// llvm_get_global_lock - returns the llvm global lock object.
- sys::Mutex &llvm_get_global_lock();
-
/// llvm_is_multithreaded - returns true if LLVM is compiled with support
/// for multiple threads, and false otherwise.
bool llvm_is_multithreaded();
#include "llvm/Support/Atomic.h"
#include "llvm/Support/MutexGuard.h"
#include <cassert>
+#include <mutex>
using namespace llvm;
static const ManagedStaticBase *StaticList = nullptr;
+// ManagedStatics can get created during execution of static constructors. As a
+// result, we cannot use a global static std::mutex object for the lock since it
+// may not have been constructed. Instead, we do a call-once initialization of
+// a pointer to a mutex. This also means that we must not "initialize" the
+// mutex with nullptr, otherwise it might get reset to nullptr after being
+// initialized by std::call_once.
+static std::once_flag MutexInitializationFlag;
+static std::recursive_mutex *ManagedStaticMutex;
+
+namespace {
+ void InitializeManagedStaticMutex() {
+ std::call_once(MutexInitializationFlag,
+ []() { ManagedStaticMutex = new std::recursive_mutex(); });
+ }
+}
+
void ManagedStaticBase::RegisterManagedStatic(void *(*Creator)(),
void (*Deleter)(void*)) const {
assert(Creator);
if (llvm_is_multithreaded()) {
- llvm::MutexGuard Lock(llvm::llvm_get_global_lock());
+ InitializeManagedStaticMutex();
+ std::lock_guard<std::recursive_mutex> Lock(*ManagedStaticMutex);
if (!Ptr) {
void* tmp = Creator();
/// llvm_shutdown - Deallocate and destroy all ManagedStatic variables.
void llvm::llvm_shutdown() {
+ InitializeManagedStaticMutex();
+ std::lock_guard<std::recursive_mutex> Lock(*ManagedStaticMutex);
+
while (StaticList)
StaticList->destroy();
}