http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49638
--- Comment #12 from Mikael Morin <mikael at gcc dot gnu.org> 2011-08-04 11:14:36 UTC --- If we are willing to do some simple expression comparisons, here is what I think should be supported (most common cases): - constants: this is the minimum - variables/dummies: for the case len=n - sub-components: for the case len=derived%char_length_comp - function calls: for the case len=len(some_char) - arithmetic operators: for the case len=n+1 So, only missing in your preliminary patch are sub-components and function. (In reply to comment #9) > > I don't know however how you will have two corresponding dummy > > arguments (from different procedures) compare equal. > > Well, the patch in comment #7 handles this by just comparing the names of the > arguments (which have to be the same in overridden procedures, so I this this > will be enough): > > + case EXPR_VARIABLE: > + if (strcmp (e1->symtree->n.sym->name, e1->symtree->n.sym->name) != 0) > + return FAILURE; > Ah, yes. > > gfc_dep_compare_expr relies on a function called > 'gfc_are_identical_variables'. > This really checks for equal symbols, which is too strict for our case here > (so > we may add an extra argument to loosen this restriction?). Yes, makes sense. Then you have components and functions almost for free.
