[flang] cannot parse a program where write statement is incorrectly positioned in contains section

[k-arrows]

Consider the following invalid Fortran program.

write(*, *) 'OK'
contains
write(*, *) 'NG'
end

If you compile the above program with gfortran, the following error message is obtained. The message correctly points out an error in the program.

$ gfortran test.f90
test.f90:3:16:

    3 | write(*, *) 'NG'
      |                1
Error: Unexpected WRITE statement in CONTAINS section at (1)

With flang-new, the following not-so-kind error message is obtained.

$ flang-new test.f90
error: Could not parse test.f90
./test.f90:3:1: error: expected 'END'
  write(*, *) 'NG'
  ^
./test.f90:3:1: in the context: END PROGRAM statement
  write(*, *) 'NG'
  ^
./test.f90:1:1: in the context: main program
  write(*, *) 'OK'
  ^
./test.f90:3:1: error: expected 'END PROGRAM'
  write(*, *) 'NG'
  ^
./test.f90:3:1: in the context: END PROGRAM statement
  write(*, *) 'NG'
  ^
./test.f90:1:1: in the context: main program
  write(*, *) 'OK'
  ^

[llvmbot]

@llvm/issue-subscribers-flang-frontend

Author: None (k-arrows)

Consider the following invalid Fortran program. ```f90 write(*, *) 'OK' contains write(*, *) 'NG' end ``` If you compile the above program with gfortran, the following error message is obtained. The message correctly points out an error in the program. ```console $ gfortran test.f90 test.f90:3:16:

3 | write(*, *) 'NG'
  |                1

Error: Unexpected WRITE statement in CONTAINS section at (1)

With flang-new, the following not-so-kind error message is obtained.
```console
$ flang-new test.f90
error: Could not parse test.f90
./test.f90:3:1: error: expected 'END'
  write(*, *) 'NG'
  ^
./test.f90:3:1: in the context: END PROGRAM statement
  write(*, *) 'NG'
  ^
./test.f90:1:1: in the context: main program
  write(*, *) 'OK'
  ^
./test.f90:3:1: error: expected 'END PROGRAM'
  write(*, *) 'NG'
  ^
./test.f90:3:1: in the context: END PROGRAM statement
  write(*, *) 'NG'
  ^
./test.f90:1:1: in the context: main program
  write(*, *) 'OK'
  ^

[klausler]

#109698