Compiler Warning (levels 1 and 3) C4115

'type' : named type definition in parentheses

The given symbol was used to define a structure, union, or enumerated type inside a parenthetical expression. The scope of this definition may be unexpected.

In a C function call, the definition has global scope. In a C++ function call, the definition has the same scope as the function being called.

This warning can also be caused by declarators within parentheses (such as prototypes) that are not parenthetical expressions.

This is a level-1 warning with C++ programs or under the /Za ANSI- compatibility command-line option. It is level 3 otherwise.

The following example causes this warning:

void func(struct S *);  /* warning */

This warning can be avoided by declaring or defining the structure outside of the parentheses before the line that caused this warning, as in:

struct S;
void func(struct S *);

or:

struct S
{
   int mem;
};
void func(struct S *);