IMPORT fails, if one imports the same symbol in multiple interface bodies of same interface block.
Found by Christopher D. Rickett, http://gcc.gnu.org/ml/fortran/2007-02/msg00466.html Test case: -------------------------------------------- module test_import implicit none type :: my_type integer :: data end type my_type interface integer function func1(param) import :: my_type type(my_type) :: param end function func1 integer function func2(param) import :: my_type type(my_type), value :: param end function func2 end interface end module test_import -------------------------------------------- Error message: integer function func1(param) 1 test_import.f03:4.17: type :: my_type 2 Error: The type my_type cannot be host associated at (1) because it is blocked by an incompatible object of the same name at (2) Simple fix: ------------------------------ Index: resolve.c =================================================================== --- resolve.c (revision 122189) +++ resolve.c (working copy) @@ -5656,7 +5656,8 @@ /* Check to see if a derived type is blocked from being host associated by the presence of another class I symbol in the same namespace. 14.6.1.3 of the standard and the discussion on comp.lang.fortran. */ - if (sym->ts.type == BT_DERIVED && sym->ns != sym->ts.derived->ns) + if (sym->ts.type == BT_DERIVED && sym->ns != sym->ts.derived->ns + && sym->ns->proc_name->attr.if_source != IFSRC_IFBODY) { gfc_symbol *s; gfc_find_symbol (sym->ts.derived->name, sym->ns, 0, &s); ------------------------------ Currently, "IMPORT :: symbol" copies the symbol like follows (simplified code; decl.c, gfc_match_import): ------------------- gfc_find_symbol (name, gfc_current_ns->parent, 1, &sym) st = gfc_new_symtree (&gfc_current_ns->sym_root, name); st->n.sym = sym; sym->refs++; sym->ns = gfc_current_ns; ------------------- Possible implementation alternative, suggested by Paul Thomas, http://gcc.gnu.org/ml/fortran/2007-02/msg00484.html > alternatively, I have wondered for a long time if > int ambiguous; in gfc_symtree is not out-of-order extravigant? > A bit-field, like symbol_attribute might be very useful. Needless to say, > imported could be added to ambiguous. If we change the implementation, we could re-add http://gcc.gnu.org/viewcvs/trunk/gcc/fortran/trans-decl.c?r1=119412&r2=119651&pathrev=119651&diff_format=h cf. PR 27546. -- Summary: IMPORT fails for same symbol in multiple interface bodies of same interface block Product: gcc Version: 4.3.0 Status: UNCONFIRMED Keywords: rejects-valid Severity: normal Priority: P3 Component: fortran AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: burnus at gcc dot gnu dot org http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30922
