'pow' : no matching overloaded function found \n"

"float spec=pow(max(dot(cameraDir,reflectDir),0.0),32);" 

Fragment Shader Compile Error！

message = 0x009df15c "ERROR: 0:1: 'pow' : no matching overloaded function found \n"

I find the answer by check StackOverFlow。

the second param of pow() is defined as float.so i changed to

"float spec=pow(max(dot(cameraDir,reflectDir),0.0),32.0);" 

it works good.