alt Hacker NewsThis is more of a problem of the C/C++ standard that it allows uninitialized variables but doesn't give them defined values, considering it "undefined behavior" to read from an uninitialized variable. Java, for example, doesn't have this particular problem because it does specify default values for variables.
But it's this and many other features of C/C++ that make it faster than Java. C/C++ developers really don't want to "pay" for something for safety.
Though, I really like the _mm_undefined_ps() intrinsics for SSE that make it clear that you're purposefully not initialising a variable. Something like that for ints and floats would be pretty sweet.