g++ doesn't compile constexpr function with assert in it

Question

template constexpr inline 
T getClamped(const T& mValue, const T& mMin, const T& mMax) 
{ 
     assert(mMin < mMax); // remove this          


        

Answer 1

g++ is right. Per the standard, a non-static assert is not permitted in a constexpr statement.

... its function-body shall be a compound-statement that contains only:
  null statements,
  static_assert-declarations,
  typedef declarations and alias-declarations that do not define classes or enumerations,
  using-declarations,
  using-directives,
  and exactly one return statement.
      -- 7.1.5/3