Alternatives to C/C++

Instead of sticking with C/C++ for performance consider:
1.Free Pascal -Small memory use,very fast, easy debug
2.OCaml - medium memory use, fast,very terse, functional and secure.
3.FreeBasic - very fast,easy to use, low memory use, supports QBasic code as dialect. Other Basics to consider: PureBasic/Gambas/PowerBASIC
4.Digital Mars D- fast, easy to write and debug, large library, transition from C/C++ much easier.Garbage collection can be turned off.

>>13
Tag bits are not unusual, lisp implementations, even high-performance CL ones do use them (unless the compiler can safely optimize them away). The result is having ints of size lesser than the CPU register size. This is a problem if the language can't promote the int to a bignum, and it can be a problem if you're writing crypto code (expected to deal in ints of the same size as the CPU register size) and need it to be efficient. In the second case, some CL compilers can still do it efficiently if you get the compiler to properly assume the types (32 or 64bit) and as long as the values are used in internal operations, it doesn't do needless fixnum<->bignum operations and the final equivalent code is just about as efficient as the C one, however that's not to say it isn't a bit of a pain to make sure the compiler gets it right (unboxed ints), maybe in some cases it's less work to just write this kind of code in C if you want unboxed ints being portable across a large variety of CL implementations (assuming the FFI supports loading your external code).