Is one variable initialization better than the other?

[Kieth89]

I see that there are 2 different ways to initialize variables in C++:

int owls = 101;	// traditional C initialization
int wrens(432);  // alternative C++ syntax, set wrens to 432 

Is one way better than the other, or is it just preference?

[Bazzy]

There's no difference with basic types.
With classes there may be difference if they have explicit constructors

[1yR4jE8b]

No difference with basic types.

With user defined types, a temporary object then copy construction for the first *may* happen instead of in-place construction. Some compilers are smart enough to not do this, although it's not guaranteed by the standard to happen. Also, if there are non-explicit constructors, then automatic type conversion may occur.

The second guarantees that an object is always constructed instead of copy constructed, so technically, more efficient.

A lot of times, they are the same.

[Disch]

With user defined types, a temporary object then copy construction for the first *may* happen instead of in-place construction.

Actually, this will never happen. MyClass foo = x; is the same as MyClass foo(x); in all cases except for maybe explicit ctors as Bazzy suggested.