Unused var error when compiling with CUDA 7.5
Created by: kexinzhao
[00:15:11]W: [Step 1/4] /paddle/paddle/fluid/operators/math/math_function.cu:282:12: error: variable ‘h_alpha’ set but not used [-Werror=unused-but-set-variable]
[00:15:11]W: [Step 1/4] const half h_alpha = static_cast<const half>(alpha);
[00:15:11]W: [Step 1/4] ^
[00:15:11]W: [Step 1/4] /paddle/paddle/fluid/operators/math/math_function.cu:283:12: error: variable ‘h_beta’ set but not used [-Werror=unused-but-set-variable]
[00:15:11]W: [Step 1/4] const half h_beta = static_cast<const half>(beta);