http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51589
Tobias Burnus <burnus at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Keywords| |diagnostic
CC| |burnus at gcc dot gnu.org
--- Comment #4 from Tobias Burnus <burnus at gcc dot gnu.org> 2011-12-17
09:15:44 UTC ---
As Harald already mentioned, GCC 4.5 (or later) support -fcheck=do to find
modifications to the DO variables at run time.
* * *
Currently, the do-variable check is done only at parse time via
"gfc_check_do_variable"; it uses gfc_state_stack to save the information about
the do variables [gfc_state_stack(->previous...)->do_variable], but this
information is lost at resolution time - on the other hand, the INTENT_OUT is
often not known at parse time.
One possibility is to generate a stack of do variables and save a link to it,
e.g., in gfc_code. Something like:
struct gfc_do_var_list {
struct gfc_do_var_list *previous;
gfc_symbol *do_var;
}
struct gfc_do_var_list *gfc_current_do_var = NULL;
The gfc_current_do_var is saved in gfc_code; every time a new DO loop is
started, a new item is generated and assigned to gfc_current_do_var - after the
DO loop, one sets gfc_current_do_var = gfc_current_do_var->previous. That will
generate a tree-like structure, which looks like a stack. (One probably needs
another linked list to store the gfc_current_do_var - as chain not as tree -
for freeing the list.)
