[Bug fortran/125458] ]13/14/15/16/17 Regression] Constant integer overflow not detected

[mikael at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=125458

--- Comment #5 from Mikael Morin <mikael at gcc dot gnu.org> ---
The difference comes from error.cc's buffered_p.
With comment #0 buffered_p is true and the error is only stored in the buffer.
With comment #2 buffered_p is false and the error is emitted. 

eval_intrinsic's signature is:
    static gfc_expr * eval_intrinsic (...)
so either the function returns a non-null expression and it is a success, or
the function returns nullptr and it is a failure.  There is no way to return a
non null expression whilst still signalling an error.