c++ - Does "&" vs. "&&" actually make a difference for compile-time flags? -

i have habit of using following syntax in compile-time flags:

#if (defined(a) & defined(b)) 

it's suggested && follows:

#if (defined(a) && defined(b)) 

i know difference between 2 operators, , in normal code && short-circuit. however, above handled compiler. matter use? affect compile time infinitesimal amount because doesn't evaluate second define()?

since defined(something) yields 0 or 1, you're guaranteed 0 or 1 on both sides, doesn't make technical difference whether use & or &&.

it's habits (using & carry on situation wrong) , writing code easy grasp simple pattern matching. & in there causes millisecond pause while 1 considers whether possibly bit-level thing.

on third hand, can't use keyword and, ¹can use in ordinary c++ code.

^{notes:
¹ visual c++ can use and via forced include of <iso646.h>.}