On Fri, May 12, 2023 at 10:54 PM Jason Merrill via Gcc-patches <gcc-patches@gcc.gnu.org> wrote: > > In the context of the recent discussion, it occurred to me that this semantic > would be useful, but currently there is no easy way to access it. > Bikeshedding > welcome; the use of this flag is a bit odd, but it has the advantage of being > accepted without error going back at least to 4.3. > > -- 8< -- > > Currently there is no flag to use to upgrade all currently-enabled pedwarns > from warning to error. -pedantic-errors also enables the -Wpedantic > pedwarns, while -Werror=pedantic uselessly makes only the -Wpedantic > pedwarns errors. > > I suggest that since -fpermissive lowers some diagnostics from error to > warning, -fno-permissive could do the reverse.
Hmm, but that makes '-fno-permissive' different from '-fpermissive -fno-permissive'? What about '-fpermissive -fno-permissive -fno-permissive' then? So I think over-loading -fno-permissive with differen semantics from negating the option is bad. Richard. > > gcc/ChangeLog: > > * doc/invoke.texi: Document -fno-permissive. > > gcc/c-family/ChangeLog: > > * c.opt (fpermissive): Accept in C and ObjC as well. > * c-opts.cc (c_common_post_options): -fno-permissive sets > global_dc->pedantic_errors. > --- > gcc/doc/invoke.texi | 7 +++++++ > gcc/c-family/c.opt | 2 +- > gcc/c-family/c-opts.cc | 4 ++++ > 3 files changed, 12 insertions(+), 1 deletion(-) > > diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi > index b92b8576027..6198df14382 100644 > --- a/gcc/doc/invoke.texi > +++ b/gcc/doc/invoke.texi > @@ -3438,11 +3438,18 @@ issue. Currently, the only such diagnostic issued by > G++ is the one for > a name having multiple meanings within a class. > > @opindex fpermissive > +@opindex fno-permissive > @item -fpermissive > Downgrade some diagnostics about nonconformant code from errors to > warnings. Thus, using @option{-fpermissive} allows some > nonconforming code to compile. > > +Conversely, @option{-fno-permissive} can be used to upgrade some > +diagnostics about nonconformant code from warnings to errors. This > +differs from @option{-pedantic-errors} in that the latter also implies > +@option{-Wpedantic}; this option does not enable additional > +diagnostics, only upgrades the severity of those that are enabled. > + > @opindex fno-pretty-templates > @opindex fpretty-templates > @item -fno-pretty-templates > diff --git a/gcc/c-family/c.opt b/gcc/c-family/c.opt > index 3333cddeece..07165d2bbe8 100644 > --- a/gcc/c-family/c.opt > +++ b/gcc/c-family/c.opt > @@ -2075,7 +2075,7 @@ C ObjC C++ ObjC++ > Look for and use PCH files even when preprocessing. > > fpermissive > -C++ ObjC++ Var(flag_permissive) > +C ObjC C++ ObjC++ Var(flag_permissive) > Downgrade conformance errors to warnings. > > fplan9-extensions > diff --git a/gcc/c-family/c-opts.cc b/gcc/c-family/c-opts.cc > index c68a2a27469..1973c068d59 100644 > --- a/gcc/c-family/c-opts.cc > +++ b/gcc/c-family/c-opts.cc > @@ -1021,6 +1021,10 @@ c_common_post_options (const char **pfilename) > SET_OPTION_IF_UNSET (&global_options, &global_options_set, > flag_delete_dead_exceptions, true); > > + if (!global_options_set.x_flag_pedantic_errors > + && global_options_set.x_flag_permissive) > + global_dc->pedantic_errors = !flag_permissive; > + > if (cxx_dialect >= cxx11) > { > /* If we're allowing C++0x constructs, don't warn about C++98 > > base-commit: 62c4d34ec005e95f000ffabd34da440dc62ac346 > -- > 2.31.1 >