[Bug fortran/89830] New: intrinsic repeat() is completely broken

[zbeekman at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89830

            Bug ID: 89830
           Summary: intrinsic repeat() is completely broken
           Product: gcc
           Version: 8.3.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: zbeekman at gmail dot com
  Target Milestone: ---

Created attachment 46026
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=46026&action=edit
Broken repeat example

The non-elemental intrinsic string function REPEAT() is completely broken. With
GFortran 8.3.0 installed via macOS Homebrew the following program fails to
compile:

```Fortran
program repeat
  implicit none
  write(*,*) repeat('a',5)
end program
```

It was compiled with:

```
gfortran -o repeat repeat_deterministic.f90
```

and produces the following error message:

```
repeat_deterministic.f90:3:19:

   write(*,*) repeat('a',5)
                   1
Error: Symbol at (1) is not appropriate for an expression
```

Furthermore, there is an error message embedded in the `REPEAT()` function
which breaks deterministic builds! It is unclear to me why the following
example compiles while the one above does not:

```Fortran
  subroutine co_broadcast_c_char(a,source_image,stat,errmsg)
    character(kind=c_char,len=*), intent(inout), volatile, target :: a
    integer(c_int), intent(in), optional :: source_image
    integer(c_int), intent(out), optional:: stat
    character(kind=1,len=*), intent(out), optional :: errmsg
    ! Local variables and constants:
    integer(c_int), allocatable :: a_cast_to_integer_array(:)

    ! Convert "a" to an integer(c_int) array where each 32-bit integer element
holds four 1-byte characters
    a_cast_to_integer_array = transfer(a,[0_c_int])
    ! Broadcast the integer(c_int) array
    call co_broadcast_c_int(a_cast_to_integer_array,source_image, stat, errmsg)
    ! Recover the characters from the broadcasted integer(c_int) array
    a = transfer(a_cast_to_integer_array,repeat(' ',len(a)))

  end subroutine
```

(This example is from OpenCoarrays 2.6.1, or you can find it at
https://github.com/sourceryinstitute/OpenCoarrays/blob/8ceb2ce8912f4f0d5317a6cce248d042b3942280/src/extensions/opencoarrays.F90#L590)

When compiled, even with the `-fno-working-directory` flag, the object file
still contains references to the full path to the source file:

```
$ strings
src/mpi/CMakeFiles/opencoarrays_mod.dir/__/extensions/opencoarrays.F90.o

Argument NCOPIES of REPEAT intrinsic is negative (its value is %ld)
At line 590 of file
/Users/ibeekman/Sandbox/OpenCoarrays/src/extensions/opencoarrays.F90
```