https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84594
--- Comment #5 from Steve Kargl <sgk at troutmask dot apl.washington.edu> --- On Wed, Feb 28, 2018 at 04:41:00PM +0000, dominiq at lps dot ens.fr wrote: > > Do you at least agree that > > (a) || flag_default_real_10 || flag_default_real_16 should be added > to flag_default_integer || flag_default_real_8 in module.c, Yes, those should probably be added. > > (b) the warning should be documented? > I thought that there was a warning in the -fdefault-* documentation about these options changing the ABI, which could cause problems. So, yes, there should be something like Warning: This option conflicts with NUMERIC_STORAGE_SIZE from ISO_FORTRAN_ENV module because it effects the underlying storage association between numeric types. It may also cause problems with changes in a library's ABI and interoperability with the C language.
