Equivalence error when arguments are array elements

[KGB99]

I have the following MRE:

      PROGRAM ERROR

      REAL               CI( 2, 2 ), CIV( 4 ), CR( 2, 2 ), CRV( 4 )

      EQUIVALENCE        ( CI( 1, 1 ), CIV( 1 ) ),
     $                   ( CR( 1, 1 ), CRV( 1 ) )

      END

which throws an error when compiling with LFortran but compiles with gfortran. The failing step is from AST to ASR. Equivalence is implemented so the following code for example does work:

      PROGRAM ERROR2

      REAL               A, B, C, D

      EQUIVALENCE        ( A, B ), ( C, D )

      END

[KGB99]

This is discussed in #2523