看gcc报错信息:

a.cpp:16: error: call of overloaded ‘function(double, double)’ is ambiguous
a.cpp:3: note: candidates are: void function(int, int)
a.cpp:9: note:                 void function(float, float)

对任一函数的调用都需要截断，这就是为什么两者都不优于另一个的原因.我怀疑你真的想要 void function(double y,double w).请记住，在 C/C++ 中，文字和参数传递的默认浮点类型是 double，而不是 float.

A call to either function would require truncation, which is why neither is preferred over the other. I suspect you really want void function(double y,double w). Remember that in C/C++, the default floating-point type for literals and parameter passing is double, NOT float.

更新

如果您真的不想将函数签名从float更改为double，您可以随时使用literals 类型为 float.如果您将后缀 f 添加到 浮点数，它们将被输入浮点数.

If you really don't want to change the function signature from float to double, you can always use literals that are typed as float. If you add the suffix f to the floating point numbers, they will be typed float.

您的示例将是 function(1.2f, 2f) 和 function(1, 2.2f).

Your examples would then be function(1.2f, 2f) and function(1, 2.2f).