[Bug c++/96862] -frounding-math -std=c++2a error: '(1.29e+2 * 6.9314718055994529e-1)' is not a constant expression

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96862

--- Comment #9 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
I don't know.
fold-const.c has:
#define START_FOLD_INIT \
  int saved_signaling_nans = flag_signaling_nans;\
  int saved_trapping_math = flag_trapping_math;\
  int saved_rounding_math = flag_rounding_math;\
  int saved_trapv = flag_trapv;\
  int saved_folding_initializer = folding_initializer;\
  flag_signaling_nans = 0;\
  flag_trapping_math = 0;\
  flag_rounding_math = 0;\
  flag_trapv = 0;\
  folding_initializer = 1;

#define END_FOLD_INIT \
  flag_signaling_nans = saved_signaling_nans;\
  flag_trapping_math = saved_trapping_math;\
  flag_rounding_math = saved_rounding_math;\
  flag_trapv = saved_trapv;\
  folding_initializer = saved_folding_initializer;