a weird COMMON fact

I have been running code foreever that had

common /name1/var1,var2
common /name1/var3,var4,var5

in the same sub-program.

The intent was, of course, to call the second common /name2/.

I corrected it and the results are still the same, because
var3,var4,var5 occur only in that sub-program (I haven't gotten round
to doing whatever I was planning to do with var3-5.)

Why doesn't the compiler (Lahey) flag this as an error or at least as
a warning?