https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108369
--- Comment #3 from kargl at gcc dot gnu.org ---
(In reply to anlauf from comment #1)
> (In reply to Ben Brewer from comment #0)
> Workaround: either use -std=legacy or fix the above argument declaration to:
>
> CHARACTER C1D001(*)*8,CVD001*8
While the workaround will work, it does so because it disables
-fallow-argument-mismatch. But, that feature emitting a bogus
error/warning.
Note the following all compile and execute. TKR is satisfied
as I discussion in comment #2.
! Compiles and executes
program foo1
character(len=10) a
a = '1234567890'
call sub1(a)
end
subroutine sub1(s)
character(len=8) s
print *, '>' // s // '<'
end
! Compiles and executes
program foo2
character(len=10) a(5)
a = '1234567890'
call sub2(a)
end
subroutine sub2(s)
character(len=8) s(2)
print *, '>' // s(1) // '<'
end
! Compiles and executes
program foo3
character(len=10) a(5)
a = '1234567890'
call sub3(a(2)(2:4))
end
subroutine sub3(s)
character(len=8) s(2)
print *, '>' // s(1) // '<'
end
But,
% gfcx -o z a.f90 && ./z
a.f90:40:13:
40 | call sub4(a(2)(2:4))
| 1
Error: Actual argument contains too few elements for dummy
argument 's' (39/80) at (1)
! Whoops
program foo4
character(len=10) a(5)
a = '1234567890'
call sub4(a(2)(2:4))
end
subroutine sub4(s)
character(len=8) s(10) ! <-- only difference from foo3
print *, '>' // s(1) // '<'
end
The give away that something is amiss is the (39/80) part of
the error message. 80 = 8*10, i.e., total number of characters.
I cannot quite get 39. 39 = 50 - 11, but 11 does not match up
with the substring length of a(2)(2:4).
Now, looking at interface.cc starting at line 3354, we have
if (a->expr->ts.type == BT_CHARACTER && !f->sym->as && where)
{
gfc_warning (0, "Character length of actual argument shorter "
"than of dummy argument %qs (%lu/%lu) at %L",
f->sym->name, actual_size, formal_size,
&a->expr->where);
goto skip_size_check;
}
else if (where)
{
/* Emit a warning for -std=legacy and an error otherwise. */
if (gfc_option.warn_std == 0)
gfc_warning (0, "Actual argument contains too few "
"elements for dummy argument %qs (%lu/%lu) "
"at %L", f->sym->name, actual_size,
formal_size, &a->expr->where);
else
gfc_error_now ("Actual argument contains too few "
"elements for dummy argument %qs (%lu/%lu) "
"at %L", f->sym->name, actual_size,
formal_size, &a->expr->where);
}
clearly we want the first branch about character length, so
`where` == NULL
