[Bug fortran/78518] New: Warning format regression

[physiker at toast2 dot net]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78518

            Bug ID: 78518
           Summary: Warning format regression
           Product: gcc
           Version: 7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: physiker at toast2 dot net
  Target Milestone: ---

When compiling the file t.f90 gfortran-7 prints the marker 1 under the second
argument. When the file is compiled by gfortran version 6 or earlier, the
marker is printed under the first argument, a, in the call to the subroutine s.

t.f90
program p
  real(4) a, b
  call s(a, b)
  print *, a, b
end program p
subroutine s(a, b)
  real(8) a, b
  a = 10.0
  b = 2*a
end subroutine s


gfortran-7 -W -Wall t.f90
t.f90:3:14:

   call s(a, b)
              1
Warning: Type mismatch in argument »a« at (1); passed REAL(4) to REAL(8)
[-Wargument-mismatch]

-*- mode: compilation; default-directory: "~/Downloads/linux_diagnose/" -*-
Compilation started at Thu Nov 24 22:37:50

gfortran-fsf-6  -W -Wall t.f90
t.f90:3:9:

   call s(a, b)
         1
Warning: Type mismatch in argument »a« at (1); passed REAL(4) to REAL(8)