COFF: Do not call std::async with std::launch::async if multithreading is disabled.

llvm-svn: 248193

1 files changed, 8 insertions, 2 deletions

diff --git a/lld/COFF/SymbolTable.cpp b/lld/COFF/SymbolTable.cpp
index accc8ef33fc..daac487e6c9 100644
--- a/lld/COFF/SymbolTable.cpp
+++ b/lld/COFF/SymbolTable.cpp
@@ -24,15 +24,21 @@ namespace lld {
 namespace coff {
 
 void SymbolTable::addFile(std::unique_ptr<InputFile> FileP) {
+#if LLVM_ENABLE_THREADS
+  std::launch Policy = std::launch::async;
+#else
+  std::launch Policy = std::launch::deferred;
+#endif
+
   InputFile *File = FileP.get();
   Files.push_back(std::move(FileP));
   if (auto *F = dyn_cast<ArchiveFile>(File)) {
     ArchiveQueue.push_back(
-        std::async(std::launch::async, [=]() { F->parse(); return F; }));
+        std::async(Policy, [=]() { F->parse(); return F; }));
     return;
   }
   ObjectQueue.push_back(
-      std::async(std::launch::async, [=]() { File->parse(); return File; }));
+      std::async(Policy, [=]() { File->parse(); return File; }));
   if (auto *F = dyn_cast<ObjectFile>(File)) {
     ObjectFiles.push_back(F);
   } else if (auto *F = dyn_cast<BitcodeFile>(File)) {