[patch, fortran, committed] Improved parse dump for coarrays

[Thomas Koenig via Gcc-patches]

Hello world,

I have just committed as obvious and simple (and as no-user-impact)
an improvement to the tree dump, plus the ability to call
debug(array_reference) in the debugger. The revision is
r11-5967.

The dump for a coarray assignment now looks like

  ASSIGN main:a(FULL)[THIS_IMAGE] 4.20000000e1
  ASSIGN main:b()[2] 2.10000000e1
  ASSIGN main:c()[*] 1.05000000e1

for

  a = 42
  b[2] = 21
  c[*] = 10.5

Previously, the coarray dumps weren't displayed, which had
led to some confusion on my part :-)

Best regards

        Thomas

Show coarrays on parse tree dump, implement debug for array references.

gcc/fortran/ChangeLog:

        * dump-parse-tree.c (show_array_ref): Also show coarrays.
        (debug): Implement for array reference.