次期 C++ ではポインタ演算は定数式になるようだ／次期 C++ の constexpr 化を考える - ボレロ村上 - ENiyGmaA Code

§5.19 Constant expressions (N3290 より抜粋) 2 A conditional-expression is a core constant expression unless it involves one of the following as a potentially evaluated subexpression (3.2), but subexpressions of logical AND (5.14), logical OR (5.15), and conditional (5.16) operations that are not evaluated are not considered [ Note: An overloaded operator invokes a function.-end note ]: (中略) a subtract

[t-murachi]

これはインパクト大きいな… そして clang …ｗ