Typo at msdn page "C++ Constant Expressions"?
It says at msdn page for c++ constant expressions that:
Nonintegral constants must be converted (either explicitly or implicitly) to integral types to be legal in a constant expression. Therefore, the following code is l开发者_如何学Goegal:
const double Size = 11.0; char chArray[(int)Size];
At least on VC++ 10.0 the second line produces: "error C2057: expected constant expression". So is it legal on some other compiler or is the msdn page simply wrong?
According to 5.19/1 :
An integral constant-expression can involve only literals (2.13), enumerators,
const
variables or static data members of integral or enumeration types initialized with constant expressions (8.5), non-type template parameters of integral or enumeration types, andsizeof
expressions. Floating literals (2.13.3) can appear only if they are cast to integral or enumeration types.
From my understanding the code is invalid, while the following is legal :
char chArray[(int)11.0];
That's not legal according to Standard C++. See 5.19/2 for the rules in the spec.
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