#if: && and || are evaluated with the same precedence #716

&& has higher precedence than || (C §6.5.13–6.5.14, C++ [expr.log.and], [expr.log.or]), but simplecpp folds both operators in a single pass from left to right.

#if 1 || 1 && 0
X
#endif

gcc and clang output X, because the condition is 1 || (1 && 0). simplecpp evaluates it as (1 || 1) && 0 and drops X.

The alternative spellings have the same problem: #if 1 or 1 and 0.