[Bug c++/69462] FLT_EVAL_METHOD and DECIMAL_DIG missing in float.h

[vogt at linux dot vnet.ibm.com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69462

--- Comment #3 from Dominik Vogt <vogt at linux dot vnet.ibm.com> ---
Is this change fit to be posted on gcc-patches?  (I have a patch for that
anyway and can post it for you if you like.)