diff --git a/llvm/lib/Transforms/Utils/AMDGPUEmitPrintf.cpp b/llvm/lib/Transforms/Utils/AMDGPUEmitPrintf.cpp
--- a/llvm/lib/Transforms/Utils/AMDGPUEmitPrintf.cpp
+++ b/llvm/lib/Transforms/Utils/AMDGPUEmitPrintf.cpp
@@ -63,7 +63,9 @@
   auto Int64Ty = Builder.getInt64Ty();
   auto M = Builder.GetInsertBlock()->getModule();
   auto Fn = M->getOrInsertFunction("__ockl_printf_begin", Int64Ty, Int64Ty);
-  M->addModuleFlag(llvm::Module::Override, "amdgpu_hostcall", 1);
+  if (!M->getModuleFlag("amdgpu_hostcall")) {
+    M->addModuleFlag(llvm::Module::Override, "amdgpu_hostcall", 1);
+  }
   return Builder.CreateCall(Fn, Version);
 }