diff --git a/lib/driver/device.cpp b/lib/driver/device.cpp
index b8477da9f..f50bd9a0b 100644
--- a/lib/driver/device.cpp
+++ b/lib/driver/device.cpp
@@ -176,7 +176,7 @@ bool Device::fp64_support() const
   switch(backend_)
   {
     case OPENCL:
-      return ocl::info<CL_DEVICE_DOUBLE_FP_CONFIG>(h_.cl());
+      return extensions().find("cl_khr_fp64")!=std::string::npos;
 
 #ifdef ISAAC_WITH_CUDA
     case CUDA:
@@ -201,7 +201,7 @@ bool Device::fp64_support() const
     switch(backend_)\
     {\
       CUDACASE(CUNAME)\
-      case OPENCL: return ocl::info<CLNAME>(h_.cl());\
+      case OPENCL: return static_cast<ret>(ocl::info<CLNAME>(h_.cl()));\
       default: throw;\
     }\
   }\
diff --git a/lib/driver/event.cpp b/lib/driver/event.cpp
index 15aa419e6..ce4be572d 100644
--- a/lib/driver/event.cpp
+++ b/lib/driver/event.cpp
@@ -38,7 +38,7 @@ long Event::elapsed_time() const
       return 1e6*time;
 #endif
     case OPENCL:
-      return ocl::info<CL_PROFILING_COMMAND_END>(h_.cl()) - ocl::info<CL_PROFILING_COMMAND_START>(h_.cl());
+      return static_cast<long>(ocl::info<CL_PROFILING_COMMAND_END>(h_.cl()) - ocl::info<CL_PROFILING_COMMAND_START>(h_.cl()));
     default:
       throw;
   }
diff --git a/lib/driver/program.cpp b/lib/driver/program.cpp
index f79363111..d272e4f81 100644
--- a/lib/driver/program.cpp
+++ b/lib/driver/program.cpp
@@ -129,7 +129,7 @@ Program::Program(Context const & context, std::string const & source) : backend_
       h_.cl() = clCreateProgramWithSource(context_.h_.cl(), 1, &csrc, &srclen, &err);
       try{
         ocl::check(clBuildProgram(h_.cl(), devices.size(), devices.data(), build_opt.c_str(), NULL, NULL));
-      }catch(ocl::exception::build_program_failure const & e){
+      }catch(ocl::exception::build_program_failure const &){
             for(std::vector<cl_device_id>::const_iterator it = devices.begin(); it != devices.end(); ++it)
             {
               std::cout << "Device : " << ocl::info<CL_DEVICE_NAME>(*it)