/* Deal with interfaces. Copyright (C) 2000, 2001, 2002, 2004, 2005, 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc. Contributed by Andy Vaught This file is part of GCC. GCC is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3, or (at your option) any later version. GCC is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GCC; see the file COPYING3. If not see . */ /* Deal with interfaces. An explicit interface is represented as a singly linked list of formal argument structures attached to the relevant symbols. For an implicit interface, the arguments don't point to symbols. Explicit interfaces point to namespaces that contain the symbols within that interface. Implicit interfaces are linked together in a singly linked list along the next_if member of symbol nodes. Since a particular symbol can only have a single explicit interface, the symbol cannot be part of multiple lists and a single next-member suffices. This is not the case for general classes, though. An operator definition is independent of just about all other uses and has it's own head pointer. Nameless interfaces: Nameless interfaces create symbols with explicit interfaces within the current namespace. They are otherwise unlinked. Generic interfaces: The generic name points to a linked list of symbols. Each symbol has an explicit interface. Each explicit interface has its own namespace containing the arguments. Module procedures are symbols in which the interface is added later when the module procedure is parsed. User operators: User-defined operators are stored in a their own set of symtrees separate from regular symbols. The symtrees point to gfc_user_op structures which in turn head up a list of relevant interfaces. Extended intrinsics and assignment: The head of these interface lists are stored in the containing namespace. Implicit interfaces: An implicit interface is represented as a singly linked list of formal argument list structures that don't point to any symbol nodes -- they just contain types. When a subprogram is defined, the program unit's name points to an interface as usual, but the link to the namespace is NULL and the formal argument list points to symbols within the same namespace as the program unit name. */ #include "config.h" #include "system.h" #include "gfortran.h" #include "match.h" /* The current_interface structure holds information about the interface currently being parsed. This structure is saved and restored during recursive interfaces. */ gfc_interface_info current_interface; /* Free a singly linked list of gfc_interface structures. */ void gfc_free_interface (gfc_interface *intr) { gfc_interface *next; for (; intr; intr = next) { next = intr->next; free (intr); } } /* Change the operators unary plus and minus into binary plus and minus respectively, leaving the rest unchanged. */ static gfc_intrinsic_op fold_unary_intrinsic (gfc_intrinsic_op op) { switch (op) { case INTRINSIC_UPLUS: op = INTRINSIC_PLUS; break; case INTRINSIC_UMINUS: op = INTRINSIC_MINUS; break; default: break; } return op; } /* Match a generic specification. Depending on which type of interface is found, the 'name' or 'op' pointers may be set. This subroutine doesn't return MATCH_NO. */ match gfc_match_generic_spec (interface_type *type, char *name, gfc_intrinsic_op *op) { char buffer[GFC_MAX_SYMBOL_LEN + 1]; match m; gfc_intrinsic_op i; if (gfc_match (" assignment ( = )") == MATCH_YES) { *type = INTERFACE_INTRINSIC_OP; *op = INTRINSIC_ASSIGN; return MATCH_YES; } if (gfc_match (" operator ( %o )", &i) == MATCH_YES) { /* Operator i/f */ *type = INTERFACE_INTRINSIC_OP; *op = fold_unary_intrinsic (i); return MATCH_YES; } *op = INTRINSIC_NONE; if (gfc_match (" operator ( ") == MATCH_YES) { m = gfc_match_defined_op_name (buffer, 1); if (m == MATCH_NO) goto syntax; if (m != MATCH_YES) return MATCH_ERROR; m = gfc_match_char (')'); if (m == MATCH_NO) goto syntax; if (m != MATCH_YES) return MATCH_ERROR; strcpy (name, buffer); *type = INTERFACE_USER_OP; return MATCH_YES; } if (gfc_match_name (buffer) == MATCH_YES) { strcpy (name, buffer); *type = INTERFACE_GENERIC; return MATCH_YES; } *type = INTERFACE_NAMELESS; return MATCH_YES; syntax: gfc_error ("Syntax error in generic specification at %C"); return MATCH_ERROR; } /* Match one of the five F95 forms of an interface statement. The matcher for the abstract interface follows. */ match gfc_match_interface (void) { char name[GFC_MAX_SYMBOL_LEN + 1]; interface_type type; gfc_symbol *sym; gfc_intrinsic_op op; match m; m = gfc_match_space (); if (gfc_match_generic_spec (&type, name, &op) == MATCH_ERROR) return MATCH_ERROR; /* If we're not looking at the end of the statement now, or if this is not a nameless interface but we did not see a space, punt. */ if (gfc_match_eos () != MATCH_YES || (type != INTERFACE_NAMELESS && m != MATCH_YES)) { gfc_error ("Syntax error: Trailing garbage in INTERFACE statement " "at %C"); return MATCH_ERROR; } current_interface.type = type; switch (type) { case INTERFACE_GENERIC: if (gfc_get_symbol (name, NULL, &sym)) return MATCH_ERROR; if (!sym->attr.generic && gfc_add_generic (&sym->attr, sym->name, NULL) == FAILURE) return MATCH_ERROR; if (sym->attr.dummy) { gfc_error ("Dummy procedure '%s' at %C cannot have a " "generic interface", sym->name); return MATCH_ERROR; } current_interface.sym = gfc_new_block = sym; break; case INTERFACE_USER_OP: current_interface.uop = gfc_get_uop (name); break; case INTERFACE_INTRINSIC_OP: current_interface.op = op; break; case INTERFACE_NAMELESS: case INTERFACE_ABSTRACT: break; } return MATCH_YES; } /* Match a F2003 abstract interface. */ match gfc_match_abstract_interface (void) { match m; if (gfc_notify_std (GFC_STD_F2003, "Fortran 2003: ABSTRACT INTERFACE at %C") == FAILURE) return MATCH_ERROR; m = gfc_match_eos (); if (m != MATCH_YES) { gfc_error ("Syntax error in ABSTRACT INTERFACE statement at %C"); return MATCH_ERROR; } current_interface.type = INTERFACE_ABSTRACT; return m; } /* Match the different sort of generic-specs that can be present after the END INTERFACE itself. */ match gfc_match_end_interface (void) { char name[GFC_MAX_SYMBOL_LEN + 1]; interface_type type; gfc_intrinsic_op op; match m; m = gfc_match_space (); if (gfc_match_generic_spec (&type, name, &op) == MATCH_ERROR) return MATCH_ERROR; /* If we're not looking at the end of the statement now, or if this is not a nameless interface but we did not see a space, punt. */ if (gfc_match_eos () != MATCH_YES || (type != INTERFACE_NAMELESS && m != MATCH_YES)) { gfc_error ("Syntax error: Trailing garbage in END INTERFACE " "statement at %C"); return MATCH_ERROR; } m = MATCH_YES; switch (current_interface.type) { case INTERFACE_NAMELESS: case INTERFACE_ABSTRACT: if (type != INTERFACE_NAMELESS) { gfc_error ("Expected a nameless interface at %C"); m = MATCH_ERROR; } break; case INTERFACE_INTRINSIC_OP: if (type != current_interface.type || op != current_interface.op) { if (current_interface.op == INTRINSIC_ASSIGN) { m = MATCH_ERROR; gfc_error ("Expected 'END INTERFACE ASSIGNMENT (=)' at %C"); } else { const char *s1, *s2; s1 = gfc_op2string (current_interface.op); s2 = gfc_op2string (op); /* The following if-statements are used to enforce C1202 from F2003. */ if ((strcmp(s1, "==") == 0 && strcmp(s2, ".eq.") == 0) || (strcmp(s1, ".eq.") == 0 && strcmp(s2, "==") == 0)) break; if ((strcmp(s1, "/=") == 0 && strcmp(s2, ".ne.") == 0) || (strcmp(s1, ".ne.") == 0 && strcmp(s2, "/=") == 0)) break; if ((strcmp(s1, "<=") == 0 && strcmp(s2, ".le.") == 0) || (strcmp(s1, ".le.") == 0 && strcmp(s2, "<=") == 0)) break; if ((strcmp(s1, "<") == 0 && strcmp(s2, ".lt.") == 0) || (strcmp(s1, ".lt.") == 0 && strcmp(s2, "<") == 0)) break; if ((strcmp(s1, ">=") == 0 && strcmp(s2, ".ge.") == 0) || (strcmp(s1, ".ge.") == 0 && strcmp(s2, ">=") == 0)) break; if ((strcmp(s1, ">") == 0 && strcmp(s2, ".gt.") == 0) || (strcmp(s1, ".gt.") == 0 && strcmp(s2, ">") == 0)) break; m = MATCH_ERROR; gfc_error ("Expecting 'END INTERFACE OPERATOR (%s)' at %C, " "but got %s", s1, s2); } } break; case INTERFACE_USER_OP: /* Comparing the symbol node names is OK because only use-associated symbols can be renamed. */ if (type != current_interface.type || strcmp (current_interface.uop->name, name) != 0) { gfc_error ("Expecting 'END INTERFACE OPERATOR (.%s.)' at %C", current_interface.uop->name); m = MATCH_ERROR; } break; case INTERFACE_GENERIC: if (type != current_interface.type || strcmp (current_interface.sym->name, name) != 0) { gfc_error ("Expecting 'END INTERFACE %s' at %C", current_interface.sym->name); m = MATCH_ERROR; } break; } return m; } /* Compare two derived types using the criteria in 4.4.2 of the standard, recursing through gfc_compare_types for the components. */ int gfc_compare_derived_types (gfc_symbol *derived1, gfc_symbol *derived2) { gfc_component *dt1, *dt2; if (derived1 == derived2) return 1; /* Special case for comparing derived types across namespaces. If the true names and module names are the same and the module name is nonnull, then they are equal. */ if (derived1 != NULL && derived2 != NULL && strcmp (derived1->name, derived2->name) == 0 && derived1->module != NULL && derived2->module != NULL && strcmp (derived1->module, derived2->module) == 0) return 1; /* Compare type via the rules of the standard. Both types must have the SEQUENCE attribute to be equal. */ if (strcmp (derived1->name, derived2->name)) return 0; if (derived1->component_access == ACCESS_PRIVATE || derived2->component_access == ACCESS_PRIVATE) return 0; if (derived1->attr.sequence == 0 || derived2->attr.sequence == 0) return 0; dt1 = derived1->components; dt2 = derived2->components; /* Since subtypes of SEQUENCE types must be SEQUENCE types as well, a simple test can speed things up. Otherwise, lots of things have to match. */ for (;;) { if (strcmp (dt1->name, dt2->name) != 0) return 0; if (dt1->attr.access != dt2->attr.access) return 0; if (dt1->attr.pointer != dt2->attr.pointer) return 0; if (dt1->attr.dimension != dt2->attr.dimension) return 0; if (dt1->attr.allocatable != dt2->attr.allocatable) return 0; if (dt1->attr.dimension && gfc_compare_array_spec (dt1->as, dt2->as) == 0) return 0; /* Make sure that link lists do not put this function into an endless recursive loop! */ if (!(dt1->ts.type == BT_DERIVED && derived1 == dt1->ts.u.derived) && !(dt1->ts.type == BT_DERIVED && derived1 == dt1->ts.u.derived) && gfc_compare_types (&dt1->ts, &dt2->ts) == 0) return 0; else if ((dt1->ts.type == BT_DERIVED && derived1 == dt1->ts.u.derived) && !(dt1->ts.type == BT_DERIVED && derived1 == dt1->ts.u.derived)) return 0; else if (!(dt1->ts.type == BT_DERIVED && derived1 == dt1->ts.u.derived) && (dt1->ts.type == BT_DERIVED && derived1 == dt1->ts.u.derived)) return 0; dt1 = dt1->next; dt2 = dt2->next; if (dt1 == NULL && dt2 == NULL) break; if (dt1 == NULL || dt2 == NULL) return 0; } return 1; } /* Compare two typespecs, recursively if necessary. */ int gfc_compare_types (gfc_typespec *ts1, gfc_typespec *ts2) { /* See if one of the typespecs is a BT_VOID, which is what is being used to allow the funcs like c_f_pointer to accept any pointer type. TODO: Possibly should narrow this to just the one typespec coming in that is for the formal arg, but oh well. */ if (ts1->type == BT_VOID || ts2->type == BT_VOID) return 1; if (ts1->type != ts2->type && ((ts1->type != BT_DERIVED && ts1->type != BT_CLASS) || (ts2->type != BT_DERIVED && ts2->type != BT_CLASS))) return 0; if (ts1->type != BT_DERIVED && ts1->type != BT_CLASS) return (ts1->kind == ts2->kind); /* Compare derived types. */ if (gfc_type_compatible (ts1, ts2)) return 1; return gfc_compare_derived_types (ts1->u.derived ,ts2->u.derived); } /* Given two symbols that are formal arguments, compare their ranks and types. Returns nonzero if they have the same rank and type, zero otherwise. */ static int compare_type_rank (gfc_symbol *s1, gfc_symbol *s2) { int r1, r2; r1 = (s1->as != NULL) ? s1->as->rank : 0; r2 = (s2->as != NULL) ? s2->as->rank : 0; if (r1 != r2) return 0; /* Ranks differ. */ return gfc_compare_types (&s1->ts, &s2->ts); } /* Given two symbols that are formal arguments, compare their types and rank and their formal interfaces if they are both dummy procedures. Returns nonzero if the same, zero if different. */ static int compare_type_rank_if (gfc_symbol *s1, gfc_symbol *s2) { if (s1 == NULL || s2 == NULL) return s1 == s2 ? 1 : 0; if (s1 == s2) return 1; if (s1->attr.flavor != FL_PROCEDURE && s2->attr.flavor != FL_PROCEDURE) return compare_type_rank (s1, s2); if (s1->attr.flavor != FL_PROCEDURE || s2->attr.flavor != FL_PROCEDURE) return 0; /* At this point, both symbols are procedures. It can happen that external procedures are compared, where one is identified by usage to be a function or subroutine but the other is not. Check TKR nonetheless for these cases. */ if (s1->attr.function == 0 && s1->attr.subroutine == 0) return s1->attr.external == 1 ? compare_type_rank (s1, s2) : 0; if (s2->attr.function == 0 && s2->attr.subroutine == 0) return s2->attr.external == 1 ? compare_type_rank (s1, s2) : 0; /* Now the type of procedure has been identified. */ if (s1->attr.function != s2->attr.function || s1->attr.subroutine != s2->attr.subroutine) return 0; if (s1->attr.function && compare_type_rank (s1, s2) == 0) return 0; /* Originally, gfortran recursed here to check the interfaces of passed procedures. This is explicitly not required by the standard. */ return 1; } /* Given a formal argument list and a keyword name, search the list for that keyword. Returns the correct symbol node if found, NULL if not found. */ static gfc_symbol * find_keyword_arg (const char *name, gfc_formal_arglist *f) { for (; f; f = f->next) if (strcmp (f->sym->name, name) == 0) return f->sym; return NULL; } /******** Interface checking subroutines **********/ /* Given an operator interface and the operator, make sure that all interfaces for that operator are legal. */ bool gfc_check_operator_interface (gfc_symbol *sym, gfc_intrinsic_op op, locus opwhere) { gfc_formal_arglist *formal; sym_intent i1, i2; bt t1, t2; int args, r1, r2, k1, k2; gcc_assert (sym); args = 0; t1 = t2 = BT_UNKNOWN; i1 = i2 = INTENT_UNKNOWN; r1 = r2 = -1; k1 = k2 = -1; for (formal = sym->formal; formal; formal = formal->next) { gfc_symbol *fsym = formal->sym; if (fsym == NULL) { gfc_error ("Alternate return cannot appear in operator " "interface at %L", &sym->declared_at); return false; } if (args == 0) { t1 = fsym->ts.type; i1 = fsym->attr.intent; r1 = (fsym->as != NULL) ? fsym->as->rank : 0; k1 = fsym->ts.kind; } if (args == 1) { t2 = fsym->ts.type; i2 = fsym->attr.intent; r2 = (fsym->as != NULL) ? fsym->as->rank : 0; k2 = fsym->ts.kind; } args++; } /* Only +, - and .not. can be unary operators. .not. cannot be a binary operator. */ if (args == 0 || args > 2 || (args == 1 && op != INTRINSIC_PLUS && op != INTRINSIC_MINUS && op != INTRINSIC_NOT) || (args == 2 && op == INTRINSIC_NOT)) { gfc_error ("Operator interface at %L has the wrong number of arguments", &sym->declared_at); return false; } /* Check that intrinsics are mapped to functions, except INTRINSIC_ASSIGN which should map to a subroutine. */ if (op == INTRINSIC_ASSIGN) { if (!sym->attr.subroutine) { gfc_error ("Assignment operator interface at %L must be " "a SUBROUTINE", &sym->declared_at); return false; } if (args != 2) { gfc_error ("Assignment operator interface at %L must have " "two arguments", &sym->declared_at); return false; } /* Allowed are (per F2003, 12.3.2.1.2 Defined assignments): - First argument an array with different rank than second, - First argument is a scalar and second an array, - Types and kinds do not conform, or - First argument is of derived type. */ if (sym->formal->sym->ts.type != BT_DERIVED && sym->formal->sym->ts.type != BT_CLASS && (r2 == 0 || r1 == r2) && (sym->formal->sym->ts.type == sym->formal->next->sym->ts.type || (gfc_numeric_ts (&sym->formal->sym->ts) && gfc_numeric_ts (&sym->formal->next->sym->ts)))) { gfc_error ("Assignment operator interface at %L must not redefine " "an INTRINSIC type assignment", &sym->declared_at); return false; } } else { if (!sym->attr.function) { gfc_error ("Intrinsic operator interface at %L must be a FUNCTION", &sym->declared_at); return false; } } /* Check intents on operator interfaces. */ if (op == INTRINSIC_ASSIGN) { if (i1 != INTENT_OUT && i1 != INTENT_INOUT) { gfc_error ("First argument of defined assignment at %L must be " "INTENT(OUT) or INTENT(INOUT)", &sym->declared_at); return false; } if (i2 != INTENT_IN) { gfc_error ("Second argument of defined assignment at %L must be " "INTENT(IN)", &sym->declared_at); return false; } } else { if (i1 != INTENT_IN) { gfc_error ("First argument of operator interface at %L must be " "INTENT(IN)", &sym->declared_at); return false; } if (args == 2 && i2 != INTENT_IN) { gfc_error ("Second argument of operator interface at %L must be " "INTENT(IN)", &sym->declared_at); return false; } } /* From now on, all we have to do is check that the operator definition doesn't conflict with an intrinsic operator. The rules for this game are defined in 7.1.2 and 7.1.3 of both F95 and F2003 standards, as well as 12.3.2.1.1 of Fortran 2003: "If the operator is an intrinsic-operator (R310), the number of function arguments shall be consistent with the intrinsic uses of that operator, and the types, kind type parameters, or ranks of the dummy arguments shall differ from those required for the intrinsic operation (7.1.2)." */ #define IS_NUMERIC_TYPE(t) \ ((t) == BT_INTEGER || (t) == BT_REAL || (t) == BT_COMPLEX) /* Unary ops are easy, do them first. */ if (op == INTRINSIC_NOT) { if (t1 == BT_LOGICAL) goto bad_repl; else return true; } if (args == 1 && (op == INTRINSIC_PLUS || op == INTRINSIC_MINUS)) { if (IS_NUMERIC_TYPE (t1)) goto bad_repl; else return true; } /* Character intrinsic operators have same character kind, thus operator definitions with operands of different character kinds are always safe. */ if (t1 == BT_CHARACTER && t2 == BT_CHARACTER && k1 != k2) return true; /* Intrinsic operators always perform on arguments of same rank, so different ranks is also always safe. (rank == 0) is an exception to that, because all intrinsic operators are elemental. */ if (r1 != r2 && r1 != 0 && r2 != 0) return true; switch (op) { case INTRINSIC_EQ: case INTRINSIC_EQ_OS: case INTRINSIC_NE: case INTRINSIC_NE_OS: if (t1 == BT_CHARACTER && t2 == BT_CHARACTER) goto bad_repl; /* Fall through. */ case INTRINSIC_PLUS: case INTRINSIC_MINUS: case INTRINSIC_TIMES: case INTRINSIC_DIVIDE: case INTRINSIC_POWER: if (IS_NUMERIC_TYPE (t1) && IS_NUMERIC_TYPE (t2)) goto bad_repl; break; case INTRINSIC_GT: case INTRINSIC_GT_OS: case INTRINSIC_GE: case INTRINSIC_GE_OS: case INTRINSIC_LT: case INTRINSIC_LT_OS: case INTRINSIC_LE: case INTRINSIC_LE_OS: if (t1 == BT_CHARACTER && t2 == BT_CHARACTER) goto bad_repl; if ((t1 == BT_INTEGER || t1 == BT_REAL) && (t2 == BT_INTEGER || t2 == BT_REAL)) goto bad_repl; break; case INTRINSIC_CONCAT: if (t1 == BT_CHARACTER && t2 == BT_CHARACTER) goto bad_repl; break; case INTRINSIC_AND: case INTRINSIC_OR: case INTRINSIC_EQV: case INTRINSIC_NEQV: if (t1 == BT_LOGICAL && t2 == BT_LOGICAL) goto bad_repl; break; default: break; } return true; #undef IS_NUMERIC_TYPE bad_repl: gfc_error ("Operator interface at %L conflicts with intrinsic interface", &opwhere); return false; } /* Given a pair of formal argument lists, we see if the two lists can be distinguished by counting the number of nonoptional arguments of a given type/rank in f1 and seeing if there are less then that number of those arguments in f2 (including optional arguments). Since this test is asymmetric, it has to be called twice to make it symmetric. Returns nonzero if the argument lists are incompatible by this test. This subroutine implements rule 1 of section 14.1.2.3 in the Fortran 95 standard. */ static int count_types_test (gfc_formal_arglist *f1, gfc_formal_arglist *f2) { int rc, ac1, ac2, i, j, k, n1; gfc_formal_arglist *f; typedef struct { int flag; gfc_symbol *sym; } arginfo; arginfo *arg; n1 = 0; for (f = f1; f; f = f->next) n1++; /* Build an array of integers that gives the same integer to arguments of the same type/rank. */ arg = XCNEWVEC (arginfo, n1); f = f1; for (i = 0; i < n1; i++, f = f->next) { arg[i].flag = -1; arg[i].sym = f->sym; } k = 0; for (i = 0; i < n1; i++) { if (arg[i].flag != -1) continue; if (arg[i].sym && arg[i].sym->attr.optional) continue; /* Skip optional arguments. */ arg[i].flag = k; /* Find other nonoptional arguments of the same type/rank. */ for (j = i + 1; j < n1; j++) if ((arg[j].sym == NULL || !arg[j].sym->attr.optional) && (compare_type_rank_if (arg[i].sym, arg[j].sym) || compare_type_rank_if (arg[j].sym, arg[i].sym))) arg[j].flag = k; k++; } /* Now loop over each distinct type found in f1. */ k = 0; rc = 0; for (i = 0; i < n1; i++) { if (arg[i].flag != k) continue; ac1 = 1; for (j = i + 1; j < n1; j++) if (arg[j].flag == k) ac1++; /* Count the number of arguments in f2 with that type, including those that are optional. */ ac2 = 0; for (f = f2; f; f = f->next) if (compare_type_rank_if (arg[i].sym, f->sym) || compare_type_rank_if (f->sym, arg[i].sym)) ac2++; if (ac1 > ac2) { rc = 1; break; } k++; } free (arg); return rc; } /* Perform the correspondence test in rule 2 of section 14.1.2.3. Returns zero if no argument is found that satisfies rule 2, nonzero otherwise. This test is also not symmetric in f1 and f2 and must be called twice. This test finds problems caused by sorting the actual argument list with keywords. For example: INTERFACE FOO SUBROUTINE F1(A, B) INTEGER :: A ; REAL :: B END SUBROUTINE F1 SUBROUTINE F2(B, A) INTEGER :: A ; REAL :: B END SUBROUTINE F1 END INTERFACE FOO At this point, 'CALL FOO(A=1, B=1.0)' is ambiguous. */ static int generic_correspondence (gfc_formal_arglist *f1, gfc_formal_arglist *f2) { gfc_formal_arglist *f2_save, *g; gfc_symbol *sym; f2_save = f2; while (f1) { if (f1->sym->attr.optional) goto next; if (f2 != NULL && (compare_type_rank (f1->sym, f2->sym) || compare_type_rank (f2->sym, f1->sym))) goto next; /* Now search for a disambiguating keyword argument starting at the current non-match. */ for (g = f1; g; g = g->next) { if (g->sym->attr.optional) continue; sym = find_keyword_arg (g->sym->name, f2_save); if (sym == NULL || !compare_type_rank (g->sym, sym)) return 1; } next: f1 = f1->next; if (f2 != NULL) f2 = f2->next; } return 0; } /* 'Compare' two formal interfaces associated with a pair of symbols. We return nonzero if there exists an actual argument list that would be ambiguous between the two interfaces, zero otherwise. 'intent_flag' specifies whether INTENT and OPTIONAL of the arguments are required to match, which is not the case for ambiguity checks.*/ int gfc_compare_interfaces (gfc_symbol *s1, gfc_symbol *s2, const char *name2, int generic_flag, int intent_flag, char *errmsg, int err_len) { gfc_formal_arglist *f1, *f2; gcc_assert (name2 != NULL); if (s1->attr.function && (s2->attr.subroutine || (!s2->attr.function && s2->ts.type == BT_UNKNOWN && gfc_get_default_type (name2, s2->ns)->type == BT_UNKNOWN))) { if (errmsg != NULL) snprintf (errmsg, err_len, "'%s' is not a function", name2); return 0; } if (s1->attr.subroutine && s2->attr.function) { if (errmsg != NULL) snprintf (errmsg, err_len, "'%s' is not a subroutine", name2); return 0; } /* If the arguments are functions, check type and kind (only for dummy procedures and procedure pointer assignments). */ if (!generic_flag && intent_flag && s1->attr.function && s2->attr.function) { if (s1->ts.type == BT_UNKNOWN) return 1; if ((s1->ts.type != s2->ts.type) || (s1->ts.kind != s2->ts.kind)) { if (errmsg != NULL) snprintf (errmsg, err_len, "Type/kind mismatch in return value " "of '%s'", name2); return 0; } } if (s1->attr.if_source == IFSRC_UNKNOWN || s2->attr.if_source == IFSRC_UNKNOWN) return 1; f1 = s1->formal; f2 = s2->formal; if (f1 == NULL && f2 == NULL) return 1; /* Special case: No arguments. */ if (generic_flag) { if (count_types_test (f1, f2) || count_types_test (f2, f1)) return 0; if (generic_correspondence (f1, f2) || generic_correspondence (f2, f1)) return 0; } else /* Perform the abbreviated correspondence test for operators (the arguments cannot be optional and are always ordered correctly). This is also done when comparing interfaces for dummy procedures and in procedure pointer assignments. */ for (;;) { /* Check existence. */ if (f1 == NULL && f2 == NULL) break; if (f1 == NULL || f2 == NULL) { if (errmsg != NULL) snprintf (errmsg, err_len, "'%s' has the wrong number of " "arguments", name2); return 0; } /* Check type and rank. */ if (!compare_type_rank (f2->sym, f1->sym)) { if (errmsg != NULL) snprintf (errmsg, err_len, "Type/rank mismatch in argument '%s'", f1->sym->name); return 0; } /* Check INTENT. */ if (intent_flag && (f1->sym->attr.intent != f2->sym->attr.intent)) { snprintf (errmsg, err_len, "INTENT mismatch in argument '%s'", f1->sym->name); return 0; } /* Check OPTIONAL. */ if (intent_flag && (f1->sym->attr.optional != f2->sym->attr.optional)) { snprintf (errmsg, err_len, "OPTIONAL mismatch in argument '%s'", f1->sym->name); return 0; } f1 = f1->next; f2 = f2->next; } return 1; } /* Given a pointer to an interface pointer, remove duplicate interfaces and make sure that all symbols are either functions or subroutines, and all of the same kind. Returns nonzero if something goes wrong. */ static int check_interface0 (gfc_interface *p, const char *interface_name) { gfc_interface *psave, *q, *qlast; psave = p; for (; p; p = p->next) { /* Make sure all symbols in the interface have been defined as functions or subroutines. */ if ((!p->sym->attr.function && !p->sym->attr.subroutine) || !p->sym->attr.if_source) { if (p->sym->attr.external) gfc_error ("Procedure '%s' in %s at %L has no explicit interface", p->sym->name, interface_name, &p->sym->declared_at); else gfc_error ("Procedure '%s' in %s at %L is neither function nor " "subroutine", p->sym->name, interface_name, &p->sym->declared_at); return 1; } /* Verify that procedures are either all SUBROUTINEs or all FUNCTIONs. */ if ((psave->sym->attr.function && !p->sym->attr.function) || (psave->sym->attr.subroutine && !p->sym->attr.subroutine)) { gfc_error ("In %s at %L procedures must be either all SUBROUTINEs" " or all FUNCTIONs", interface_name, &p->sym->declared_at); return 1; } if (p->sym->attr.proc == PROC_INTERNAL && gfc_notify_std (GFC_STD_GNU, "Extension: Internal procedure '%s' " "in %s at %L", p->sym->name, interface_name, &p->sym->declared_at) == FAILURE) return 1; } p = psave; /* Remove duplicate interfaces in this interface list. */ for (; p; p = p->next) { qlast = p; for (q = p->next; q;) { if (p->sym != q->sym) { qlast = q; q = q->next; } else { /* Duplicate interface. */ qlast->next = q->next; free (q); q = qlast->next; } } } return 0; } /* Check lists of interfaces to make sure that no two interfaces are ambiguous. Duplicate interfaces (from the same symbol) are OK here. */ static int check_interface1 (gfc_interface *p, gfc_interface *q0, int generic_flag, const char *interface_name, bool referenced) { gfc_interface *q; for (; p; p = p->next) for (q = q0; q; q = q->next) { if (p->sym == q->sym) continue; /* Duplicates OK here. */ if (p->sym->name == q->sym->name && p->sym->module == q->sym->module) continue; if (gfc_compare_interfaces (p->sym, q->sym, q->sym->name, generic_flag, 0, NULL, 0)) { if (referenced) gfc_error ("Ambiguous interfaces '%s' and '%s' in %s at %L", p->sym->name, q->sym->name, interface_name, &p->where); else if (!p->sym->attr.use_assoc && q->sym->attr.use_assoc) gfc_warning ("Ambiguous interfaces '%s' and '%s' in %s at %L", p->sym->name, q->sym->name, interface_name, &p->where); else gfc_warning ("Although not referenced, '%s' has ambiguous " "interfaces at %L", interface_name, &p->where); return 1; } } return 0; } /* Check the generic and operator interfaces of symbols to make sure that none of the interfaces conflict. The check has to be done after all of the symbols are actually loaded. */ static void check_sym_interfaces (gfc_symbol *sym) { char interface_name[100]; gfc_interface *p; if (sym->ns != gfc_current_ns) return; if (sym->generic != NULL) { sprintf (interface_name, "generic interface '%s'", sym->name); if (check_interface0 (sym->generic, interface_name)) return; for (p = sym->generic; p; p = p->next) { if (p->sym->attr.mod_proc && (p->sym->attr.if_source != IFSRC_DECL || p->sym->attr.procedure)) { gfc_error ("'%s' at %L is not a module procedure", p->sym->name, &p->where); return; } } /* Originally, this test was applied to host interfaces too; this is incorrect since host associated symbols, from any source, cannot be ambiguous with local symbols. */ check_interface1 (sym->generic, sym->generic, 1, interface_name, sym->attr.referenced || !sym->attr.use_assoc); } } static void check_uop_interfaces (gfc_user_op *uop) { char interface_name[100]; gfc_user_op *uop2; gfc_namespace *ns; sprintf (interface_name, "operator interface '%s'", uop->name); if (check_interface0 (uop->op, interface_name)) return; for (ns = gfc_current_ns; ns; ns = ns->parent) { uop2 = gfc_find_uop (uop->name, ns); if (uop2 == NULL) continue; check_interface1 (uop->op, uop2->op, 0, interface_name, true); } } /* Given an intrinsic op, return an equivalent op if one exists, or INTRINSIC_NONE otherwise. */ gfc_intrinsic_op gfc_equivalent_op (gfc_intrinsic_op op) { switch(op) { case INTRINSIC_EQ: return INTRINSIC_EQ_OS; case INTRINSIC_EQ_OS: return INTRINSIC_EQ; case INTRINSIC_NE: return INTRINSIC_NE_OS; case INTRINSIC_NE_OS: return INTRINSIC_NE; case INTRINSIC_GT: return INTRINSIC_GT_OS; case INTRINSIC_GT_OS: return INTRINSIC_GT; case INTRINSIC_GE: return INTRINSIC_GE_OS; case INTRINSIC_GE_OS: return INTRINSIC_GE; case INTRINSIC_LT: return INTRINSIC_LT_OS; case INTRINSIC_LT_OS: return INTRINSIC_LT; case INTRINSIC_LE: return INTRINSIC_LE_OS; case INTRINSIC_LE_OS: return INTRINSIC_LE; default: return INTRINSIC_NONE; } } /* For the namespace, check generic, user operator and intrinsic operator interfaces for consistency and to remove duplicate interfaces. We traverse the whole namespace, counting on the fact that most symbols will not have generic or operator interfaces. */ void gfc_check_interfaces (gfc_namespace *ns) { gfc_namespace *old_ns, *ns2; char interface_name[100]; int i; old_ns = gfc_current_ns; gfc_current_ns = ns; gfc_traverse_ns (ns, check_sym_interfaces); gfc_traverse_user_op (ns, check_uop_interfaces); for (i = GFC_INTRINSIC_BEGIN; i != GFC_INTRINSIC_END; i++) { if (i == INTRINSIC_USER) continue; if (i == INTRINSIC_ASSIGN) strcpy (interface_name, "intrinsic assignment operator"); else sprintf (interface_name, "intrinsic '%s' operator", gfc_op2string ((gfc_intrinsic_op) i)); if (check_interface0 (ns->op[i], interface_name)) continue; if (ns->op[i]) gfc_check_operator_interface (ns->op[i]->sym, (gfc_intrinsic_op) i, ns->op[i]->where); for (ns2 = ns; ns2; ns2 = ns2->parent) { gfc_intrinsic_op other_op; if (check_interface1 (ns->op[i], ns2->op[i], 0, interface_name, true)) goto done; /* i should be gfc_intrinsic_op, but has to be int with this cast here for stupid C++ compatibility rules. */ other_op = gfc_equivalent_op ((gfc_intrinsic_op) i); if (other_op != INTRINSIC_NONE && check_interface1 (ns->op[i], ns2->op[other_op], 0, interface_name, true)) goto done; } } done: gfc_current_ns = old_ns; } static int symbol_rank (gfc_symbol *sym) { return (sym->as == NULL) ? 0 : sym->as->rank; } /* Given a symbol of a formal argument list and an expression, if the formal argument is allocatable, check that the actual argument is allocatable. Returns nonzero if compatible, zero if not compatible. */ static int compare_allocatable (gfc_symbol *formal, gfc_expr *actual) { symbol_attribute attr; if (formal->attr.allocatable || (formal->ts.type == BT_CLASS && CLASS_DATA (formal)->attr.allocatable)) { attr = gfc_expr_attr (actual); if (!attr.allocatable) return 0; } return 1; } /* Given a symbol of a formal argument list and an expression, if the formal argument is a pointer, see if the actual argument is a pointer. Returns nonzero if compatible, zero if not compatible. */ static int compare_pointer (gfc_symbol *formal, gfc_expr *actual) { symbol_attribute attr; if (formal->attr.pointer) { attr = gfc_expr_attr (actual); /* Fortran 2008 allows non-pointer actual arguments. */ if (!attr.pointer && attr.target && formal->attr.intent == INTENT_IN) return 2; if (!attr.pointer) return 0; } return 1; } /* Emit clear error messages for rank mismatch. */ static void argument_rank_mismatch (const char *name, locus *where, int rank1, int rank2) { if (rank1 == 0) { gfc_error ("Rank mismatch in argument '%s' at %L " "(scalar and rank-%d)", name, where, rank2); } else if (rank2 == 0) { gfc_error ("Rank mismatch in argument '%s' at %L " "(rank-%d and scalar)", name, where, rank1); } else { gfc_error ("Rank mismatch in argument '%s' at %L " "(rank-%d and rank-%d)", name, where, rank1, rank2); } } /* Given a symbol of a formal argument list and an expression, see if the two are compatible as arguments. Returns nonzero if compatible, zero if not compatible. */ static int compare_parameter (gfc_symbol *formal, gfc_expr *actual, int ranks_must_agree, int is_elemental, locus *where) { gfc_ref *ref; bool rank_check, is_pointer; /* If the formal arg has type BT_VOID, it's to one of the iso_c_binding procs c_f_pointer or c_f_procpointer, and we need to accept most pointers the user could give us. This should allow that. */ if (formal->ts.type == BT_VOID) return 1; if (formal->ts.type == BT_DERIVED && formal->ts.u.derived && formal->ts.u.derived->ts.is_iso_c && actual->ts.type == BT_DERIVED && actual->ts.u.derived && actual->ts.u.derived->ts.is_iso_c) return 1; if (formal->ts.type == BT_CLASS && actual->ts.type == BT_DERIVED) /* Make sure the vtab symbol is present when the module variables are generated. */ gfc_find_derived_vtab (actual->ts.u.derived); if (actual->ts.type == BT_PROCEDURE) { char err[200]; gfc_symbol *act_sym = actual->symtree->n.sym; if (formal->attr.flavor != FL_PROCEDURE) { if (where) gfc_error ("Invalid procedure argument at %L", &actual->where); return 0; } if (!gfc_compare_interfaces (formal, act_sym, act_sym->name, 0, 1, err, sizeof(err))) { if (where) gfc_error ("Interface mismatch in dummy procedure '%s' at %L: %s", formal->name, &actual->where, err); return 0; } if (formal->attr.function && !act_sym->attr.function) { gfc_add_function (&act_sym->attr, act_sym->name, &act_sym->declared_at); if (act_sym->ts.type == BT_UNKNOWN && gfc_set_default_type (act_sym, 1, act_sym->ns) == FAILURE) return 0; } else if (formal->attr.subroutine && !act_sym->attr.subroutine) gfc_add_subroutine (&act_sym->attr, act_sym->name, &act_sym->declared_at); return 1; } /* F2008, C1241. */ if (formal->attr.pointer && formal->attr.contiguous && !gfc_is_simply_contiguous (actual, true)) { if (where) gfc_error ("Actual argument to contiguous pointer dummy '%s' at %L " "must be simply contigous", formal->name, &actual->where); return 0; } if ((actual->expr_type != EXPR_NULL || actual->ts.type != BT_UNKNOWN) && actual->ts.type != BT_HOLLERITH && !gfc_compare_types (&formal->ts, &actual->ts)) { if (where) gfc_error ("Type mismatch in argument '%s' at %L; passed %s to %s", formal->name, &actual->where, gfc_typename (&actual->ts), gfc_typename (&formal->ts)); return 0; } /* F2003, 12.5.2.5. */ if (formal->ts.type == BT_CLASS && (CLASS_DATA (formal)->attr.class_pointer || CLASS_DATA (formal)->attr.allocatable)) { if (actual->ts.type != BT_CLASS) { if (where) gfc_error ("Actual argument to '%s' at %L must be polymorphic", formal->name, &actual->where); return 0; } if (CLASS_DATA (actual)->ts.u.derived != CLASS_DATA (formal)->ts.u.derived) { if (where) gfc_error ("Actual argument to '%s' at %L must have the same " "declared type", formal->name, &actual->where); return 0; } } if (formal->attr.codimension && !gfc_is_coarray (actual)) { if (where) gfc_error ("Actual argument to '%s' at %L must be a coarray", formal->name, &actual->where); return 0; } if (formal->attr.codimension && formal->attr.allocatable) { gfc_ref *last = NULL; for (ref = actual->ref; ref; ref = ref->next) if (ref->type == REF_COMPONENT) last = ref; /* F2008, 12.5.2.6. */ if ((last && last->u.c.component->as->corank != formal->as->corank) || (!last && actual->symtree->n.sym->as->corank != formal->as->corank)) { if (where) gfc_error ("Corank mismatch in argument '%s' at %L (%d and %d)", formal->name, &actual->where, formal->as->corank, last ? last->u.c.component->as->corank : actual->symtree->n.sym->as->corank); return 0; } } if (formal->attr.codimension) { /* F2008, 12.5.2.8. */ if (formal->attr.dimension && (formal->attr.contiguous || formal->as->type != AS_ASSUMED_SHAPE) && gfc_expr_attr (actual).dimension && !gfc_is_simply_contiguous (actual, true)) { if (where) gfc_error ("Actual argument to '%s' at %L must be simply " "contiguous", formal->name, &actual->where); return 0; } /* F2008, C1303 and C1304. */ if (formal->attr.intent != INTENT_INOUT && (((formal->ts.type == BT_DERIVED || formal->ts.type == BT_CLASS) && formal->ts.u.derived->from_intmod == INTMOD_ISO_FORTRAN_ENV && formal->ts.u.derived->intmod_sym_id == ISOFORTRAN_LOCK_TYPE) || formal->attr.lock_comp)) { if (where) gfc_error ("Actual argument to non-INTENT(INOUT) dummy '%s' at %L, " "which is LOCK_TYPE or has a LOCK_TYPE component", formal->name, &actual->where); return 0; } } /* F2008, C1239/C1240. */ if (actual->expr_type == EXPR_VARIABLE && (actual->symtree->n.sym->attr.asynchronous || actual->symtree->n.sym->attr.volatile_) && (formal->attr.asynchronous || formal->attr.volatile_) && actual->rank && !gfc_is_simply_contiguous (actual, true) && ((formal->as->type != AS_ASSUMED_SHAPE && !formal->attr.pointer) || formal->attr.contiguous)) { if (where) gfc_error ("Dummy argument '%s' has to be a pointer or assumed-shape " "array without CONTIGUOUS attribute - as actual argument at" " %L is not simply contiguous and both are ASYNCHRONOUS " "or VOLATILE", formal->name, &actual->where); return 0; } if (formal->attr.allocatable && !formal->attr.codimension && gfc_expr_attr (actual).codimension) { if (formal->attr.intent == INTENT_OUT) { if (where) gfc_error ("Passing coarray at %L to allocatable, noncoarray, " "INTENT(OUT) dummy argument '%s'", &actual->where, formal->name); return 0; } else if (gfc_option.warn_surprising && where && formal->attr.intent != INTENT_IN) gfc_warning ("Passing coarray at %L to allocatable, noncoarray dummy " "argument '%s', which is invalid if the allocation status" " is modified", &actual->where, formal->name); } if (symbol_rank (formal) == actual->rank) return 1; rank_check = where != NULL && !is_elemental && formal->as && (formal->as->type == AS_ASSUMED_SHAPE || formal->as->type == AS_DEFERRED) && actual->expr_type != EXPR_NULL; /* Scalar & coindexed, see: F2008, Section 12.5.2.4. */ if (rank_check || ranks_must_agree || (formal->attr.pointer && actual->expr_type != EXPR_NULL) || (actual->rank != 0 && !(is_elemental || formal->attr.dimension)) || (actual->rank == 0 && formal->as->type == AS_ASSUMED_SHAPE && actual->expr_type != EXPR_NULL) || (actual->rank == 0 && formal->attr.dimension && gfc_is_coindexed (actual))) { if (where) argument_rank_mismatch (formal->name, &actual->where, symbol_rank (formal), actual->rank); return 0; } else if (actual->rank != 0 && (is_elemental || formal->attr.dimension)) return 1; /* At this point, we are considering a scalar passed to an array. This is valid (cf. F95 12.4.1.1, F2003 12.4.1.2, and F2008 12.5.2.4), - if the actual argument is (a substring of) an element of a non-assumed-shape/non-pointer/non-polymorphic array; or - (F2003) if the actual argument is of type character of default/c_char kind. */ is_pointer = actual->expr_type == EXPR_VARIABLE ? actual->symtree->n.sym->attr.pointer : false; for (ref = actual->ref; ref; ref = ref->next) { if (ref->type == REF_COMPONENT) is_pointer = ref->u.c.component->attr.pointer; else if (ref->type == REF_ARRAY && ref->u.ar.type == AR_ELEMENT && ref->u.ar.dimen > 0 && (!ref->next || (ref->next->type == REF_SUBSTRING && !ref->next->next))) break; } if (actual->ts.type == BT_CLASS && actual->expr_type != EXPR_NULL) { if (where) gfc_error ("Polymorphic scalar passed to array dummy argument '%s' " "at %L", formal->name, &actual->where); return 0; } if (actual->expr_type != EXPR_NULL && ref && actual->ts.type != BT_CHARACTER && (is_pointer || ref->u.ar.as->type == AS_ASSUMED_SHAPE)) { if (where) gfc_error ("Element of assumed-shaped or pointer " "array passed to array dummy argument '%s' at %L", formal->name, &actual->where); return 0; } if (actual->ts.type == BT_CHARACTER && actual->expr_type != EXPR_NULL && (!ref || is_pointer || ref->u.ar.as->type == AS_ASSUMED_SHAPE)) { if (formal->ts.kind != 1 && (gfc_option.allow_std & GFC_STD_GNU) == 0) { if (where) gfc_error ("Extension: Scalar non-default-kind, non-C_CHAR-kind " "CHARACTER actual argument with array dummy argument " "'%s' at %L", formal->name, &actual->where); return 0; } if (where && (gfc_option.allow_std & GFC_STD_F2003) == 0) { gfc_error ("Fortran 2003: Scalar CHARACTER actual argument with " "array dummy argument '%s' at %L", formal->name, &actual->where); return 0; } else if ((gfc_option.allow_std & GFC_STD_F2003) == 0) return 0; else return 1; } if (ref == NULL && actual->expr_type != EXPR_NULL) { if (where) argument_rank_mismatch (formal->name, &actual->where, symbol_rank (formal), actual->rank); return 0; } return 1; } /* Returns the storage size of a symbol (formal argument) or zero if it cannot be determined. */ static unsigned long get_sym_storage_size (gfc_symbol *sym) { int i; unsigned long strlen, elements; if (sym->ts.type == BT_CHARACTER) { if (sym->ts.u.cl && sym->ts.u.cl->length && sym->ts.u.cl->length->expr_type == EXPR_CONSTANT) strlen = mpz_get_ui (sym->ts.u.cl->length->value.integer); else return 0; } else strlen = 1; if (symbol_rank (sym) == 0) return strlen; elements = 1; if (sym->as->type != AS_EXPLICIT) return 0; for (i = 0; i < sym->as->rank; i++) { if (!sym->as || sym->as->upper[i]->expr_type != EXPR_CONSTANT || sym->as->lower[i]->expr_type != EXPR_CONSTANT) return 0; elements *= mpz_get_si (sym->as->upper[i]->value.integer) - mpz_get_si (sym->as->lower[i]->value.integer) + 1L; } return strlen*elements; } /* Returns the storage size of an expression (actual argument) or zero if it cannot be determined. For an array element, it returns the remaining size as the element sequence consists of all storage units of the actual argument up to the end of the array. */ static unsigned long get_expr_storage_size (gfc_expr *e) { int i; long int strlen, elements; long int substrlen = 0; bool is_str_storage = false; gfc_ref *ref; if (e == NULL) return 0; if (e->ts.type == BT_CHARACTER) { if (e->ts.u.cl && e->ts.u.cl->length && e->ts.u.cl->length->expr_type == EXPR_CONSTANT) strlen = mpz_get_si (e->ts.u.cl->length->value.integer); else if (e->expr_type == EXPR_CONSTANT && (e->ts.u.cl == NULL || e->ts.u.cl->length == NULL)) strlen = e->value.character.length; else return 0; } else strlen = 1; /* Length per element. */ if (e->rank == 0 && !e->ref) return strlen; elements = 1; if (!e->ref) { if (!e->shape) return 0; for (i = 0; i < e->rank; i++) elements *= mpz_get_si (e->shape[i]); return elements*strlen; } for (ref = e->ref; ref; ref = ref->next) { if (ref->type == REF_SUBSTRING && ref->u.ss.start && ref->u.ss.start->expr_type == EXPR_CONSTANT) { if (is_str_storage) { /* The string length is the substring length. Set now to full string length. */ if (ref->u.ss.length == NULL || ref->u.ss.length->length->expr_type != EXPR_CONSTANT) return 0; strlen = mpz_get_ui (ref->u.ss.length->length->value.integer); } substrlen = strlen - mpz_get_ui (ref->u.ss.start->value.integer) + 1; continue; } if (ref->type == REF_ARRAY && ref->u.ar.type == AR_SECTION && ref->u.ar.start && ref->u.ar.end && ref->u.ar.stride && ref->u.ar.as->upper) for (i = 0; i < ref->u.ar.dimen; i++) { long int start, end, stride; stride = 1; if (ref->u.ar.stride[i]) { if (ref->u.ar.stride[i]->expr_type == EXPR_CONSTANT) stride = mpz_get_si (ref->u.ar.stride[i]->value.integer); else return 0; } if (ref->u.ar.start[i]) { if (ref->u.ar.start[i]->expr_type == EXPR_CONSTANT) start = mpz_get_si (ref->u.ar.start[i]->value.integer); else return 0; } else if (ref->u.ar.as->lower[i] && ref->u.ar.as->lower[i]->expr_type == EXPR_CONSTANT) start = mpz_get_si (ref->u.ar.as->lower[i]->value.integer); else return 0; if (ref->u.ar.end[i]) { if (ref->u.ar.end[i]->expr_type == EXPR_CONSTANT) end = mpz_get_si (ref->u.ar.end[i]->value.integer); else return 0; } else if (ref->u.ar.as->upper[i] && ref->u.ar.as->upper[i]->expr_type == EXPR_CONSTANT) end = mpz_get_si (ref->u.ar.as->upper[i]->value.integer); else return 0; elements *= (end - start)/stride + 1L; } else if (ref->type == REF_ARRAY && ref->u.ar.type == AR_FULL && ref->u.ar.as->lower && ref->u.ar.as->upper) for (i = 0; i < ref->u.ar.as->rank; i++) { if (ref->u.ar.as->lower[i] && ref->u.ar.as->upper[i] && ref->u.ar.as->lower[i]->expr_type == EXPR_CONSTANT && ref->u.ar.as->upper[i]->expr_type == EXPR_CONSTANT) elements *= mpz_get_si (ref->u.ar.as->upper[i]->value.integer) - mpz_get_si (ref->u.ar.as->lower[i]->value.integer) + 1L; else return 0; } else if (ref->type == REF_ARRAY && ref->u.ar.type == AR_ELEMENT && e->expr_type == EXPR_VARIABLE) { if (ref->u.ar.as->type == AS_ASSUMED_SHAPE || e->symtree->n.sym->attr.pointer) { elements = 1; continue; } /* Determine the number of remaining elements in the element sequence for array element designators. */ is_str_storage = true; for (i = ref->u.ar.dimen - 1; i >= 0; i--) { if (ref->u.ar.start[i] == NULL || ref->u.ar.start[i]->expr_type != EXPR_CONSTANT || ref->u.ar.as->upper[i] == NULL || ref->u.ar.as->lower[i] == NULL || ref->u.ar.as->upper[i]->expr_type != EXPR_CONSTANT || ref->u.ar.as->lower[i]->expr_type != EXPR_CONSTANT) return 0; elements = elements * (mpz_get_si (ref->u.ar.as->upper[i]->value.integer) - mpz_get_si (ref->u.ar.as->lower[i]->value.integer) + 1L) - (mpz_get_si (ref->u.ar.start[i]->value.integer) - mpz_get_si (ref->u.ar.as->lower[i]->value.integer)); } } } if (substrlen) return (is_str_storage) ? substrlen + (elements-1)*strlen : elements*strlen; else return elements*strlen; } /* Given an expression, check whether it is an array section which has a vector subscript. If it has, one is returned, otherwise zero. */ int gfc_has_vector_subscript (gfc_expr *e) { int i; gfc_ref *ref; if (e == NULL || e->rank == 0 || e->expr_type != EXPR_VARIABLE) return 0; for (ref = e->ref; ref; ref = ref->next) if (ref->type == REF_ARRAY && ref->u.ar.type == AR_SECTION) for (i = 0; i < ref->u.ar.dimen; i++) if (ref->u.ar.dimen_type[i] == DIMEN_VECTOR) return 1; return 0; } /* Given formal and actual argument lists, see if they are compatible. If they are compatible, the actual argument list is sorted to correspond with the formal list, and elements for missing optional arguments are inserted. If WHERE pointer is nonnull, then we issue errors when things don't match instead of just returning the status code. */ static int compare_actual_formal (gfc_actual_arglist **ap, gfc_formal_arglist *formal, int ranks_must_agree, int is_elemental, locus *where) { gfc_actual_arglist **new_arg, *a, *actual, temp; gfc_formal_arglist *f; int i, n, na; unsigned long actual_size, formal_size; actual = *ap; if (actual == NULL && formal == NULL) return 1; n = 0; for (f = formal; f; f = f->next) n++; new_arg = XALLOCAVEC (gfc_actual_arglist *, n); for (i = 0; i < n; i++) new_arg[i] = NULL; na = 0; f = formal; i = 0; for (a = actual; a; a = a->next, f = f->next) { /* Look for keywords but ignore g77 extensions like %VAL. */ if (a->name != NULL && a->name[0] != '%') { i = 0; for (f = formal; f; f = f->next, i++) { if (f->sym == NULL) continue; if (strcmp (f->sym->name, a->name) == 0) break; } if (f == NULL) { if (where) gfc_error ("Keyword argument '%s' at %L is not in " "the procedure", a->name, &a->expr->where); return 0; } if (new_arg[i] != NULL) { if (where) gfc_error ("Keyword argument '%s' at %L is already associated " "with another actual argument", a->name, &a->expr->where); return 0; } } if (f == NULL) { if (where) gfc_error ("More actual than formal arguments in procedure " "call at %L", where); return 0; } if (f->sym == NULL && a->expr == NULL) goto match; if (f->sym == NULL) { if (where) gfc_error ("Missing alternate return spec in subroutine call " "at %L", where); return 0; } if (a->expr == NULL) { if (where) gfc_error ("Unexpected alternate return spec in subroutine " "call at %L", where); return 0; } if (a->expr->expr_type == EXPR_NULL && !f->sym->attr.pointer && (f->sym->attr.allocatable || !f->sym->attr.optional || (gfc_option.allow_std & GFC_STD_F2008) == 0)) { if (where && (f->sym->attr.allocatable || !f->sym->attr.optional)) gfc_error ("Unexpected NULL() intrinsic at %L to dummy '%s'", where, f->sym->name); else if (where) gfc_error ("Fortran 2008: Null pointer at %L to non-pointer " "dummy '%s'", where, f->sym->name); return 0; } if (!compare_parameter (f->sym, a->expr, ranks_must_agree, is_elemental, where)) return 0; /* Special case for character arguments. For allocatable, pointer and assumed-shape dummies, the string length needs to match exactly. */ if (a->expr->ts.type == BT_CHARACTER && a->expr->ts.u.cl && a->expr->ts.u.cl->length && a->expr->ts.u.cl->length->expr_type == EXPR_CONSTANT && f->sym->ts.u.cl && f->sym->ts.u.cl && f->sym->ts.u.cl->length && f->sym->ts.u.cl->length->expr_type == EXPR_CONSTANT && (f->sym->attr.pointer || f->sym->attr.allocatable || (f->sym->as && f->sym->as->type == AS_ASSUMED_SHAPE)) && (mpz_cmp (a->expr->ts.u.cl->length->value.integer, f->sym->ts.u.cl->length->value.integer) != 0)) { if (where && (f->sym->attr.pointer || f->sym->attr.allocatable)) gfc_warning ("Character length mismatch (%ld/%ld) between actual " "argument and pointer or allocatable dummy argument " "'%s' at %L", mpz_get_si (a->expr->ts.u.cl->length->value.integer), mpz_get_si (f->sym->ts.u.cl->length->value.integer), f->sym->name, &a->expr->where); else if (where) gfc_warning ("Character length mismatch (%ld/%ld) between actual " "argument and assumed-shape dummy argument '%s' " "at %L", mpz_get_si (a->expr->ts.u.cl->length->value.integer), mpz_get_si (f->sym->ts.u.cl->length->value.integer), f->sym->name, &a->expr->where); return 0; } if ((f->sym->attr.pointer || f->sym->attr.allocatable) && f->sym->ts.deferred != a->expr->ts.deferred && a->expr->ts.type == BT_CHARACTER) { if (where) gfc_error ("Actual argument argument at %L to allocatable or " "pointer dummy argument '%s' must have a deferred " "length type parameter if and only if the dummy has one", &a->expr->where, f->sym->name); return 0; } actual_size = get_expr_storage_size (a->expr); formal_size = get_sym_storage_size (f->sym); if (actual_size != 0 && actual_size < formal_size && a->expr->ts.type != BT_PROCEDURE && f->sym->attr.flavor != FL_PROCEDURE) { if (a->expr->ts.type == BT_CHARACTER && !f->sym->as && where) gfc_warning ("Character length of actual argument shorter " "than of dummy argument '%s' (%lu/%lu) at %L", f->sym->name, actual_size, formal_size, &a->expr->where); else if (where) gfc_warning ("Actual argument contains too few " "elements for dummy argument '%s' (%lu/%lu) at %L", f->sym->name, actual_size, formal_size, &a->expr->where); return 0; } /* Satisfy 12.4.1.3 by ensuring that a procedure pointer actual argument is provided for a procedure pointer formal argument. */ if (f->sym->attr.proc_pointer && !((a->expr->expr_type == EXPR_VARIABLE && a->expr->symtree->n.sym->attr.proc_pointer) || (a->expr->expr_type == EXPR_FUNCTION && a->expr->symtree->n.sym->result->attr.proc_pointer) || gfc_is_proc_ptr_comp (a->expr, NULL))) { if (where) gfc_error ("Expected a procedure pointer for argument '%s' at %L", f->sym->name, &a->expr->where); return 0; } /* Satisfy 12.4.1.2 by ensuring that a procedure actual argument is provided for a procedure formal argument. */ if (a->expr->ts.type != BT_PROCEDURE && !gfc_is_proc_ptr_comp (a->expr, NULL) && a->expr->expr_type == EXPR_VARIABLE && f->sym->attr.flavor == FL_PROCEDURE) { if (where) gfc_error ("Expected a procedure for argument '%s' at %L", f->sym->name, &a->expr->where); return 0; } if (f->sym->attr.flavor == FL_PROCEDURE && f->sym->attr.pure && a->expr->ts.type == BT_PROCEDURE && !a->expr->symtree->n.sym->attr.pure) { if (where) gfc_error ("Expected a PURE procedure for argument '%s' at %L", f->sym->name, &a->expr->where); return 0; } if (f->sym->as && f->sym->as->type == AS_ASSUMED_SHAPE && a->expr->expr_type == EXPR_VARIABLE && a->expr->symtree->n.sym->as && a->expr->symtree->n.sym->as->type == AS_ASSUMED_SIZE && (a->expr->ref == NULL || (a->expr->ref->type == REF_ARRAY && a->expr->ref->u.ar.type == AR_FULL))) { if (where) gfc_error ("Actual argument for '%s' cannot be an assumed-size" " array at %L", f->sym->name, where); return 0; } if (a->expr->expr_type != EXPR_NULL && compare_pointer (f->sym, a->expr) == 0) { if (where) gfc_error ("Actual argument for '%s' must be a pointer at %L", f->sym->name, &a->expr->where); return 0; } if (a->expr->expr_type != EXPR_NULL && (gfc_option.allow_std & GFC_STD_F2008) == 0 && compare_pointer (f->sym, a->expr) == 2) { if (where) gfc_error ("Fortran 2008: Non-pointer actual argument at %L to " "pointer dummy '%s'", &a->expr->where,f->sym->name); return 0; } /* Fortran 2008, C1242. */ if (f->sym->attr.pointer && gfc_is_coindexed (a->expr)) { if (where) gfc_error ("Coindexed actual argument at %L to pointer " "dummy '%s'", &a->expr->where, f->sym->name); return 0; } /* Fortran 2008, 12.5.2.5 (no constraint). */ if (a->expr->expr_type == EXPR_VARIABLE && f->sym->attr.intent != INTENT_IN && f->sym->attr.allocatable && gfc_is_coindexed (a->expr)) { if (where) gfc_error ("Coindexed actual argument at %L to allocatable " "dummy '%s' requires INTENT(IN)", &a->expr->where, f->sym->name); return 0; } /* Fortran 2008, C1237. */ if (a->expr->expr_type == EXPR_VARIABLE && (f->sym->attr.asynchronous || f->sym->attr.volatile_) && gfc_is_coindexed (a->expr) && (a->expr->symtree->n.sym->attr.volatile_ || a->expr->symtree->n.sym->attr.asynchronous)) { if (where) gfc_error ("Coindexed ASYNCHRONOUS or VOLATILE actual argument at " "at %L requires that dummy %s' has neither " "ASYNCHRONOUS nor VOLATILE", &a->expr->where, f->sym->name); return 0; } /* Fortran 2008, 12.5.2.4 (no constraint). */ if (a->expr->expr_type == EXPR_VARIABLE && f->sym->attr.intent != INTENT_IN && !f->sym->attr.value && gfc_is_coindexed (a->expr) && gfc_has_ultimate_allocatable (a->expr)) { if (where) gfc_error ("Coindexed actual argument at %L with allocatable " "ultimate component to dummy '%s' requires either VALUE " "or INTENT(IN)", &a->expr->where, f->sym->name); return 0; } if (a->expr->expr_type != EXPR_NULL && compare_allocatable (f->sym, a->expr) == 0) { if (where) gfc_error ("Actual argument for '%s' must be ALLOCATABLE at %L", f->sym->name, &a->expr->where); return 0; } /* Check intent = OUT/INOUT for definable actual argument. */ if ((f->sym->attr.intent == INTENT_OUT || f->sym->attr.intent == INTENT_INOUT)) { const char* context = (where ? _("actual argument to INTENT = OUT/INOUT") : NULL); if (f->sym->attr.pointer && gfc_check_vardef_context (a->expr, true, false, context) == FAILURE) return 0; if (gfc_check_vardef_context (a->expr, false, false, context) == FAILURE) return 0; } if ((f->sym->attr.intent == INTENT_OUT || f->sym->attr.intent == INTENT_INOUT || f->sym->attr.volatile_ || f->sym->attr.asynchronous) && gfc_has_vector_subscript (a->expr)) { if (where) gfc_error ("Array-section actual argument with vector " "subscripts at %L is incompatible with INTENT(OUT), " "INTENT(INOUT), VOLATILE or ASYNCHRONOUS attribute " "of the dummy argument '%s'", &a->expr->where, f->sym->name); return 0; } /* C1232 (R1221) For an actual argument which is an array section or an assumed-shape array, the dummy argument shall be an assumed- shape array, if the dummy argument has the VOLATILE attribute. */ if (f->sym->attr.volatile_ && a->expr->symtree->n.sym->as && a->expr->symtree->n.sym->as->type == AS_ASSUMED_SHAPE && !(f->sym->as && f->sym->as->type == AS_ASSUMED_SHAPE)) { if (where) gfc_error ("Assumed-shape actual argument at %L is " "incompatible with the non-assumed-shape " "dummy argument '%s' due to VOLATILE attribute", &a->expr->where,f->sym->name); return 0; } if (f->sym->attr.volatile_ && a->expr->ref && a->expr->ref->u.ar.type == AR_SECTION && !(f->sym->as && f->sym->as->type == AS_ASSUMED_SHAPE)) { if (where) gfc_error ("Array-section actual argument at %L is " "incompatible with the non-assumed-shape " "dummy argument '%s' due to VOLATILE attribute", &a->expr->where,f->sym->name); return 0; } /* C1233 (R1221) For an actual argument which is a pointer array, the dummy argument shall be an assumed-shape or pointer array, if the dummy argument has the VOLATILE attribute. */ if (f->sym->attr.volatile_ && a->expr->symtree->n.sym->attr.pointer && a->expr->symtree->n.sym->as && !(f->sym->as && (f->sym->as->type == AS_ASSUMED_SHAPE || f->sym->attr.pointer))) { if (where) gfc_error ("Pointer-array actual argument at %L requires " "an assumed-shape or pointer-array dummy " "argument '%s' due to VOLATILE attribute", &a->expr->where,f->sym->name); return 0; } match: if (a == actual) na = i; new_arg[i++] = a; } /* Make sure missing actual arguments are optional. */ i = 0; for (f = formal; f; f = f->next, i++) { if (new_arg[i] != NULL) continue; if (f->sym == NULL) { if (where) gfc_error ("Missing alternate return spec in subroutine call " "at %L", where); return 0; } if (!f->sym->attr.optional) { if (where) gfc_error ("Missing actual argument for argument '%s' at %L", f->sym->name, where); return 0; } } /* The argument lists are compatible. We now relink a new actual argument list with null arguments in the right places. The head of the list remains the head. */ for (i = 0; i < n; i++) if (new_arg[i] == NULL) new_arg[i] = gfc_get_actual_arglist (); if (na != 0) { temp = *new_arg[0]; *new_arg[0] = *actual; *actual = temp; a = new_arg[0]; new_arg[0] = new_arg[na]; new_arg[na] = a; } for (i = 0; i < n - 1; i++) new_arg[i]->next = new_arg[i + 1]; new_arg[i]->next = NULL; if (*ap == NULL && n > 0) *ap = new_arg[0]; /* Note the types of omitted optional arguments. */ for (a = *ap, f = formal; a; a = a->next, f = f->next) if (a->expr == NULL && a->label == NULL) a->missing_arg_type = f->sym->ts.type; return 1; } typedef struct { gfc_formal_arglist *f; gfc_actual_arglist *a; } argpair; /* qsort comparison function for argument pairs, with the following order: - p->a->expr == NULL - p->a->expr->expr_type != EXPR_VARIABLE - growing p->a->expr->symbol. */ static int pair_cmp (const void *p1, const void *p2) { const gfc_actual_arglist *a1, *a2; /* *p1 and *p2 are elements of the to-be-sorted array. */ a1 = ((const argpair *) p1)->a; a2 = ((const argpair *) p2)->a; if (!a1->expr) { if (!a2->expr) return 0; return -1; } if (!a2->expr) return 1; if (a1->expr->expr_type != EXPR_VARIABLE) { if (a2->expr->expr_type != EXPR_VARIABLE) return 0; return -1; } if (a2->expr->expr_type != EXPR_VARIABLE) return 1; return a1->expr->symtree->n.sym < a2->expr->symtree->n.sym; } /* Given two expressions from some actual arguments, test whether they refer to the same expression. The analysis is conservative. Returning FAILURE will produce no warning. */ static gfc_try compare_actual_expr (gfc_expr *e1, gfc_expr *e2) { const gfc_ref *r1, *r2; if (!e1 || !e2 || e1->expr_type != EXPR_VARIABLE || e2->expr_type != EXPR_VARIABLE || e1->symtree->n.sym != e2->symtree->n.sym) return FAILURE; /* TODO: improve comparison, see expr.c:show_ref(). */ for (r1 = e1->ref, r2 = e2->ref; r1 && r2; r1 = r1->next, r2 = r2->next) { if (r1->type != r2->type) return FAILURE; switch (r1->type) { case REF_ARRAY: if (r1->u.ar.type != r2->u.ar.type) return FAILURE; /* TODO: At the moment, consider only full arrays; we could do better. */ if (r1->u.ar.type != AR_FULL || r2->u.ar.type != AR_FULL) return FAILURE; break; case REF_COMPONENT: if (r1->u.c.component != r2->u.c.component) return FAILURE; break; case REF_SUBSTRING: return FAILURE; default: gfc_internal_error ("compare_actual_expr(): Bad component code"); } } if (!r1 && !r2) return SUCCESS; return FAILURE; } /* Given formal and actual argument lists that correspond to one another, check that identical actual arguments aren't not associated with some incompatible INTENTs. */ static gfc_try check_some_aliasing (gfc_formal_arglist *f, gfc_actual_arglist *a) { sym_intent f1_intent, f2_intent; gfc_formal_arglist *f1; gfc_actual_arglist *a1; size_t n, i, j; argpair *p; gfc_try t = SUCCESS; n = 0; for (f1 = f, a1 = a;; f1 = f1->next, a1 = a1->next) { if (f1 == NULL && a1 == NULL) break; if (f1 == NULL || a1 == NULL) gfc_internal_error ("check_some_aliasing(): List mismatch"); n++; } if (n == 0) return t; p = XALLOCAVEC (argpair, n); for (i = 0, f1 = f, a1 = a; i < n; i++, f1 = f1->next, a1 = a1->next) { p[i].f = f1; p[i].a = a1; } qsort (p, n, sizeof (argpair), pair_cmp); for (i = 0; i < n; i++) { if (!p[i].a->expr || p[i].a->expr->expr_type != EXPR_VARIABLE || p[i].a->expr->ts.type == BT_PROCEDURE) continue; f1_intent = p[i].f->sym->attr.intent; for (j = i + 1; j < n; j++) { /* Expected order after the sort. */ if (!p[j].a->expr || p[j].a->expr->expr_type != EXPR_VARIABLE) gfc_internal_error ("check_some_aliasing(): corrupted data"); /* Are the expression the same? */ if (compare_actual_expr (p[i].a->expr, p[j].a->expr) == FAILURE) break; f2_intent = p[j].f->sym->attr.intent; if ((f1_intent == INTENT_IN && f2_intent == INTENT_OUT) || (f1_intent == INTENT_OUT && f2_intent == INTENT_IN)) { gfc_warning ("Same actual argument associated with INTENT(%s) " "argument '%s' and INTENT(%s) argument '%s' at %L", gfc_intent_string (f1_intent), p[i].f->sym->name, gfc_intent_string (f2_intent), p[j].f->sym->name, &p[i].a->expr->where); t = FAILURE; } } } return t; } /* Given a symbol of a formal argument list and an expression, return nonzero if their intents are compatible, zero otherwise. */ static int compare_parameter_intent (gfc_symbol *formal, gfc_expr *actual) { if (actual->symtree->n.sym->attr.pointer && !formal->attr.pointer) return 1; if (actual->symtree->n.sym->attr.intent != INTENT_IN) return 1; if (formal->attr.intent == INTENT_INOUT || formal->attr.intent == INTENT_OUT) return 0; return 1; } /* Given formal and actual argument lists that correspond to one another, check that they are compatible in the sense that intents are not mismatched. */ static gfc_try check_intents (gfc_formal_arglist *f, gfc_actual_arglist *a) { sym_intent f_intent; for (;; f = f->next, a = a->next) { if (f == NULL && a == NULL) break; if (f == NULL || a == NULL) gfc_internal_error ("check_intents(): List mismatch"); if (a->expr == NULL || a->expr->expr_type != EXPR_VARIABLE) continue; f_intent = f->sym->attr.intent; if (!compare_parameter_intent(f->sym, a->expr)) { gfc_error ("Procedure argument at %L is INTENT(IN) while interface " "specifies INTENT(%s)", &a->expr->where, gfc_intent_string (f_intent)); return FAILURE; } if (gfc_pure (NULL) && gfc_impure_variable (a->expr->symtree->n.sym)) { if (f_intent == INTENT_INOUT || f_intent == INTENT_OUT) { gfc_error ("Procedure argument at %L is local to a PURE " "procedure and is passed to an INTENT(%s) argument", &a->expr->where, gfc_intent_string (f_intent)); return FAILURE; } if (f->sym->attr.pointer) { gfc_error ("Procedure argument at %L is local to a PURE " "procedure and has the POINTER attribute", &a->expr->where); return FAILURE; } } /* Fortran 2008, C1283. */ if (gfc_pure (NULL) && gfc_is_coindexed (a->expr)) { if (f_intent == INTENT_INOUT || f_intent == INTENT_OUT) { gfc_error ("Coindexed actual argument at %L in PURE procedure " "is passed to an INTENT(%s) argument", &a->expr->where, gfc_intent_string (f_intent)); return FAILURE; } if (f->sym->attr.pointer) { gfc_error ("Coindexed actual argument at %L in PURE procedure " "is passed to a POINTER dummy argument", &a->expr->where); return FAILURE; } } /* F2008, Section 12.5.2.4. */ if (a->expr->ts.type == BT_CLASS && f->sym->ts.type == BT_CLASS && gfc_is_coindexed (a->expr)) { gfc_error ("Coindexed polymorphic actual argument at %L is passed " "polymorphic dummy argument '%s'", &a->expr->where, f->sym->name); return FAILURE; } } return SUCCESS; } /* Check how a procedure is used against its interface. If all goes well, the actual argument list will also end up being properly sorted. */ void gfc_procedure_use (gfc_symbol *sym, gfc_actual_arglist **ap, locus *where) { /* Warn about calls with an implicit interface. Special case for calling a ISO_C_BINDING becase c_loc and c_funloc are pseudo-unknown. Additionally, warn about procedures not explicitly declared at all if requested. */ if (sym->attr.if_source == IFSRC_UNKNOWN && ! sym->attr.is_iso_c) { if (gfc_option.warn_implicit_interface) gfc_warning ("Procedure '%s' called with an implicit interface at %L", sym->name, where); else if (gfc_option.warn_implicit_procedure && sym->attr.proc == PROC_UNKNOWN) gfc_warning ("Procedure '%s' called at %L is not explicitly declared", sym->name, where); } if (sym->attr.if_source == IFSRC_UNKNOWN) { gfc_actual_arglist *a; if (sym->attr.pointer) { gfc_error("The pointer object '%s' at %L must have an explicit " "function interface or be declared as array", sym->name, where); return; } if (sym->attr.allocatable && !sym->attr.external) { gfc_error("The allocatable object '%s' at %L must have an explicit " "function interface or be declared as array", sym->name, where); return; } if (sym->attr.allocatable) { gfc_error("Allocatable function '%s' at %L must have an explicit " "function interface", sym->name, where); return; } for (a = *ap; a; a = a->next) { /* Skip g77 keyword extensions like %VAL, %REF, %LOC. */ if (a->name != NULL && a->name[0] != '%') { gfc_error("Keyword argument requires explicit interface " "for procedure '%s' at %L", sym->name, &a->expr->where); break; } /* F2008, C1303 and C1304. */ if (a->expr && (a->expr->ts.type == BT_DERIVED || a->expr->ts.type == BT_CLASS) && ((a->expr->ts.u.derived->from_intmod == INTMOD_ISO_FORTRAN_ENV && a->expr->ts.u.derived->intmod_sym_id == ISOFORTRAN_LOCK_TYPE) || gfc_expr_attr (a->expr).lock_comp)) { gfc_error("Actual argument of LOCK_TYPE or with LOCK_TYPE " "component at %L requires an explicit interface for " "procedure '%s'", &a->expr->where, sym->name); break; } } return; } if (!compare_actual_formal (ap, sym->formal, 0, sym->attr.elemental, where)) return; check_intents (sym->formal, *ap); if (gfc_option.warn_aliasing) check_some_aliasing (sym->formal, *ap); } /* Check how a procedure pointer component is used against its interface. If all goes well, the actual argument list will also end up being properly sorted. Completely analogous to gfc_procedure_use. */ void gfc_ppc_use (gfc_component *comp, gfc_actual_arglist **ap, locus *where) { /* Warn about calls with an implicit interface. Special case for calling a ISO_C_BINDING becase c_loc and c_funloc are pseudo-unknown. */ if (gfc_option.warn_implicit_interface && comp->attr.if_source == IFSRC_UNKNOWN && !comp->attr.is_iso_c) gfc_warning ("Procedure pointer component '%s' called with an implicit " "interface at %L", comp->name, where); if (comp->attr.if_source == IFSRC_UNKNOWN) { gfc_actual_arglist *a; for (a = *ap; a; a = a->next) { /* Skip g77 keyword extensions like %VAL, %REF, %LOC. */ if (a->name != NULL && a->name[0] != '%') { gfc_error("Keyword argument requires explicit interface " "for procedure pointer component '%s' at %L", comp->name, &a->expr->where); break; } } return; } if (!compare_actual_formal (ap, comp->formal, 0, comp->attr.elemental, where)) return; check_intents (comp->formal, *ap); if (gfc_option.warn_aliasing) check_some_aliasing (comp->formal, *ap); } /* Try if an actual argument list matches the formal list of a symbol, respecting the symbol's attributes like ELEMENTAL. This is used for GENERIC resolution. */ bool gfc_arglist_matches_symbol (gfc_actual_arglist** args, gfc_symbol* sym) { bool r; gcc_assert (sym->attr.flavor == FL_PROCEDURE); r = !sym->attr.elemental; if (compare_actual_formal (args, sym->formal, r, !r, NULL)) { check_intents (sym->formal, *args); if (gfc_option.warn_aliasing) check_some_aliasing (sym->formal, *args); return true; } return false; } /* Given an interface pointer and an actual argument list, search for a formal argument list that matches the actual. If found, returns a pointer to the symbol of the correct interface. Returns NULL if not found. */ gfc_symbol * gfc_search_interface (gfc_interface *intr, int sub_flag, gfc_actual_arglist **ap) { gfc_symbol *elem_sym = NULL; for (; intr; intr = intr->next) { if (sub_flag && intr->sym->attr.function) continue; if (!sub_flag && intr->sym->attr.subroutine) continue; if (gfc_arglist_matches_symbol (ap, intr->sym)) { /* Satisfy 12.4.4.1 such that an elemental match has lower weight than a non-elemental match. */ if (intr->sym->attr.elemental) { elem_sym = intr->sym; continue; } return intr->sym; } } return elem_sym ? elem_sym : NULL; } /* Do a brute force recursive search for a symbol. */ static gfc_symtree * find_symtree0 (gfc_symtree *root, gfc_symbol *sym) { gfc_symtree * st; if (root->n.sym == sym) return root; st = NULL; if (root->left) st = find_symtree0 (root->left, sym); if (root->right && ! st) st = find_symtree0 (root->right, sym); return st; } /* Find a symtree for a symbol. */ gfc_symtree * gfc_find_sym_in_symtree (gfc_symbol *sym) { gfc_symtree *st; gfc_namespace *ns; /* First try to find it by name. */ gfc_find_sym_tree (sym->name, gfc_current_ns, 1, &st); if (st && st->n.sym == sym) return st; /* If it's been renamed, resort to a brute-force search. */ /* TODO: avoid having to do this search. If the symbol doesn't exist in the symtree for the current namespace, it should probably be added. */ for (ns = gfc_current_ns; ns; ns = ns->parent) { st = find_symtree0 (ns->sym_root, sym); if (st) return st; } gfc_internal_error ("Unable to find symbol %s", sym->name); /* Not reached. */ } /* See if the arglist to an operator-call contains a derived-type argument with a matching type-bound operator. If so, return the matching specific procedure defined as operator-target as well as the base-object to use (which is the found derived-type argument with operator). The generic name, if any, is transmitted to the final expression via 'gname'. */ static gfc_typebound_proc* matching_typebound_op (gfc_expr** tb_base, gfc_actual_arglist* args, gfc_intrinsic_op op, const char* uop, const char ** gname) { gfc_actual_arglist* base; for (base = args; base; base = base->next) if (base->expr->ts.type == BT_DERIVED || base->expr->ts.type == BT_CLASS) { gfc_typebound_proc* tb; gfc_symbol* derived; gfc_try result; if (base->expr->ts.type == BT_CLASS) { if (!gfc_expr_attr (base->expr).class_ok) continue; derived = CLASS_DATA (base->expr)->ts.u.derived; } else derived = base->expr->ts.u.derived; if (op == INTRINSIC_USER) { gfc_symtree* tb_uop; gcc_assert (uop); tb_uop = gfc_find_typebound_user_op (derived, &result, uop, false, NULL); if (tb_uop) tb = tb_uop->n.tb; else tb = NULL; } else tb = gfc_find_typebound_intrinsic_op (derived, &result, op, false, NULL); /* This means we hit a PRIVATE operator which is use-associated and should thus not be seen. */ if (result == FAILURE) tb = NULL; /* Look through the super-type hierarchy for a matching specific binding. */ for (; tb; tb = tb->overridden) { gfc_tbp_generic* g; gcc_assert (tb->is_generic); for (g = tb->u.generic; g; g = g->next) { gfc_symbol* target; gfc_actual_arglist* argcopy; bool matches; gcc_assert (g->specific); if (g->specific->error) continue; target = g->specific->u.specific->n.sym; /* Check if this arglist matches the formal. */ argcopy = gfc_copy_actual_arglist (args); matches = gfc_arglist_matches_symbol (&argcopy, target); gfc_free_actual_arglist (argcopy); /* Return if we found a match. */ if (matches) { *tb_base = base->expr; *gname = g->specific_st->name; return g->specific; } } } } return NULL; } /* For the 'actual arglist' of an operator call and a specific typebound procedure that has been found the target of a type-bound operator, build the appropriate EXPR_COMPCALL and resolve it. We take this indirection over type-bound procedures rather than resolving type-bound operators 'directly' so that we can reuse the existing logic. */ static void build_compcall_for_operator (gfc_expr* e, gfc_actual_arglist* actual, gfc_expr* base, gfc_typebound_proc* target, const char *gname) { e->expr_type = EXPR_COMPCALL; e->value.compcall.tbp = target; e->value.compcall.name = gname ? gname : "$op"; e->value.compcall.actual = actual; e->value.compcall.base_object = base; e->value.compcall.ignore_pass = 1; e->value.compcall.assign = 0; } /* This subroutine is called when an expression is being resolved. The expression node in question is either a user defined operator or an intrinsic operator with arguments that aren't compatible with the operator. This subroutine builds an actual argument list corresponding to the operands, then searches for a compatible interface. If one is found, the expression node is replaced with the appropriate function call. real_error is an additional output argument that specifies if FAILURE is because of some real error and not because no match was found. */ gfc_try gfc_extend_expr (gfc_expr *e, bool *real_error) { gfc_actual_arglist *actual; gfc_symbol *sym; gfc_namespace *ns; gfc_user_op *uop; gfc_intrinsic_op i; const char *gname; sym = NULL; actual = gfc_get_actual_arglist (); actual->expr = e->value.op.op1; *real_error = false; gname = NULL; if (e->value.op.op2 != NULL) { actual->next = gfc_get_actual_arglist (); actual->next->expr = e->value.op.op2; } i = fold_unary_intrinsic (e->value.op.op); if (i == INTRINSIC_USER) { for (ns = gfc_current_ns; ns; ns = ns->parent) { uop = gfc_find_uop (e->value.op.uop->name, ns); if (uop == NULL) continue; sym = gfc_search_interface (uop->op, 0, &actual); if (sym != NULL) break; } } else { for (ns = gfc_current_ns; ns; ns = ns->parent) { /* Due to the distinction between '==' and '.eq.' and friends, one has to check if either is defined. */ switch (i) { #define CHECK_OS_COMPARISON(comp) \ case INTRINSIC_##comp: \ case INTRINSIC_##comp##_OS: \ sym = gfc_search_interface (ns->op[INTRINSIC_##comp], 0, &actual); \ if (!sym) \ sym = gfc_search_interface (ns->op[INTRINSIC_##comp##_OS], 0, &actual); \ break; CHECK_OS_COMPARISON(EQ) CHECK_OS_COMPARISON(NE) CHECK_OS_COMPARISON(GT) CHECK_OS_COMPARISON(GE) CHECK_OS_COMPARISON(LT) CHECK_OS_COMPARISON(LE) #undef CHECK_OS_COMPARISON default: sym = gfc_search_interface (ns->op[i], 0, &actual); } if (sym != NULL) break; } } /* TODO: Do an ambiguity-check and error if multiple matching interfaces are found rather than just taking the first one and not checking further. */ if (sym == NULL) { gfc_typebound_proc* tbo; gfc_expr* tb_base; /* See if we find a matching type-bound operator. */ if (i == INTRINSIC_USER) tbo = matching_typebound_op (&tb_base, actual, i, e->value.op.uop->name, &gname); else switch (i) { #define CHECK_OS_COMPARISON(comp) \ case INTRINSIC_##comp: \ case INTRINSIC_##comp##_OS: \ tbo = matching_typebound_op (&tb_base, actual, \ INTRINSIC_##comp, NULL, &gname); \ if (!tbo) \ tbo = matching_typebound_op (&tb_base, actual, \ INTRINSIC_##comp##_OS, NULL, &gname); \ break; CHECK_OS_COMPARISON(EQ) CHECK_OS_COMPARISON(NE) CHECK_OS_COMPARISON(GT) CHECK_OS_COMPARISON(GE) CHECK_OS_COMPARISON(LT) CHECK_OS_COMPARISON(LE) #undef CHECK_OS_COMPARISON default: tbo = matching_typebound_op (&tb_base, actual, i, NULL, &gname); break; } /* If there is a matching typebound-operator, replace the expression with a call to it and succeed. */ if (tbo) { gfc_try result; gcc_assert (tb_base); build_compcall_for_operator (e, actual, tb_base, tbo, gname); result = gfc_resolve_expr (e); if (result == FAILURE) *real_error = true; return result; } /* Don't use gfc_free_actual_arglist(). */ free (actual->next); free (actual); return FAILURE; } /* Change the expression node to a function call. */ e->expr_type = EXPR_FUNCTION; e->symtree = gfc_find_sym_in_symtree (sym); e->value.function.actual = actual; e->value.function.esym = NULL; e->value.function.isym = NULL; e->value.function.name = NULL; e->user_operator = 1; if (gfc_resolve_expr (e) == FAILURE) { *real_error = true; return FAILURE; } return SUCCESS; } /* Tries to replace an assignment code node with a subroutine call to the subroutine associated with the assignment operator. Return SUCCESS if the node was replaced. On FAILURE, no error is generated. */ gfc_try gfc_extend_assign (gfc_code *c, gfc_namespace *ns) { gfc_actual_arglist *actual; gfc_expr *lhs, *rhs; gfc_symbol *sym; const char *gname; gname = NULL; lhs = c->expr1; rhs = c->expr2; /* Don't allow an intrinsic assignment to be replaced. */ if (lhs->ts.type != BT_DERIVED && lhs->ts.type != BT_CLASS && (rhs->rank == 0 || rhs->rank == lhs->rank) && (lhs->ts.type == rhs->ts.type || (gfc_numeric_ts (&lhs->ts) && gfc_numeric_ts (&rhs->ts)))) return FAILURE; actual = gfc_get_actual_arglist (); actual->expr = lhs; actual->next = gfc_get_actual_arglist (); actual->next->expr = rhs; sym = NULL; for (; ns; ns = ns->parent) { sym = gfc_search_interface (ns->op[INTRINSIC_ASSIGN], 1, &actual); if (sym != NULL) break; } /* TODO: Ambiguity-check, see above for gfc_extend_expr. */ if (sym == NULL) { gfc_typebound_proc* tbo; gfc_expr* tb_base; /* See if we find a matching type-bound assignment. */ tbo = matching_typebound_op (&tb_base, actual, INTRINSIC_ASSIGN, NULL, &gname); /* If there is one, replace the expression with a call to it and succeed. */ if (tbo) { gcc_assert (tb_base); c->expr1 = gfc_get_expr (); build_compcall_for_operator (c->expr1, actual, tb_base, tbo, gname); c->expr1->value.compcall.assign = 1; c->expr1->where = c->loc; c->expr2 = NULL; c->op = EXEC_COMPCALL; /* c is resolved from the caller, so no need to do it here. */ return SUCCESS; } free (actual->next); free (actual); return FAILURE; } /* Replace the assignment with the call. */ c->op = EXEC_ASSIGN_CALL; c->symtree = gfc_find_sym_in_symtree (sym); c->expr1 = NULL; c->expr2 = NULL; c->ext.actual = actual; return SUCCESS; } /* Make sure that the interface just parsed is not already present in the given interface list. Ambiguity isn't checked yet since module procedures can be present without interfaces. */ static gfc_try check_new_interface (gfc_interface *base, gfc_symbol *new_sym) { gfc_interface *ip; for (ip = base; ip; ip = ip->next) { if (ip->sym == new_sym) { gfc_error ("Entity '%s' at %C is already present in the interface", new_sym->name); return FAILURE; } } return SUCCESS; } /* Add a symbol to the current interface. */ gfc_try gfc_add_interface (gfc_symbol *new_sym) { gfc_interface **head, *intr; gfc_namespace *ns; gfc_symbol *sym; switch (current_interface.type) { case INTERFACE_NAMELESS: case INTERFACE_ABSTRACT: return SUCCESS; case INTERFACE_INTRINSIC_OP: for (ns = current_interface.ns; ns; ns = ns->parent) switch (current_interface.op) { case INTRINSIC_EQ: case INTRINSIC_EQ_OS: if (check_new_interface (ns->op[INTRINSIC_EQ], new_sym) == FAILURE || check_new_interface (ns->op[INTRINSIC_EQ_OS], new_sym) == FAILURE) return FAILURE; break; case INTRINSIC_NE: case INTRINSIC_NE_OS: if (check_new_interface (ns->op[INTRINSIC_NE], new_sym) == FAILURE || check_new_interface (ns->op[INTRINSIC_NE_OS], new_sym) == FAILURE) return FAILURE; break; case INTRINSIC_GT: case INTRINSIC_GT_OS: if (check_new_interface (ns->op[INTRINSIC_GT], new_sym) == FAILURE || check_new_interface (ns->op[INTRINSIC_GT_OS], new_sym) == FAILURE) return FAILURE; break; case INTRINSIC_GE: case INTRINSIC_GE_OS: if (check_new_interface (ns->op[INTRINSIC_GE], new_sym) == FAILURE || check_new_interface (ns->op[INTRINSIC_GE_OS], new_sym) == FAILURE) return FAILURE; break; case INTRINSIC_LT: case INTRINSIC_LT_OS: if (check_new_interface (ns->op[INTRINSIC_LT], new_sym) == FAILURE || check_new_interface (ns->op[INTRINSIC_LT_OS], new_sym) == FAILURE) return FAILURE; break; case INTRINSIC_LE: case INTRINSIC_LE_OS: if (check_new_interface (ns->op[INTRINSIC_LE], new_sym) == FAILURE || check_new_interface (ns->op[INTRINSIC_LE_OS], new_sym) == FAILURE) return FAILURE; break; default: if (check_new_interface (ns->op[current_interface.op], new_sym) == FAILURE) return FAILURE; } head = ¤t_interface.ns->op[current_interface.op]; break; case INTERFACE_GENERIC: for (ns = current_interface.ns; ns; ns = ns->parent) { gfc_find_symbol (current_interface.sym->name, ns, 0, &sym); if (sym == NULL) continue; if (check_new_interface (sym->generic, new_sym) == FAILURE) return FAILURE; } head = ¤t_interface.sym->generic; break; case INTERFACE_USER_OP: if (check_new_interface (current_interface.uop->op, new_sym) == FAILURE) return FAILURE; head = ¤t_interface.uop->op; break; default: gfc_internal_error ("gfc_add_interface(): Bad interface type"); } intr = gfc_get_interface (); intr->sym = new_sym; intr->where = gfc_current_locus; intr->next = *head; *head = intr; return SUCCESS; } gfc_interface * gfc_current_interface_head (void) { switch (current_interface.type) { case INTERFACE_INTRINSIC_OP: return current_interface.ns->op[current_interface.op]; break; case INTERFACE_GENERIC: return current_interface.sym->generic; break; case INTERFACE_USER_OP: return current_interface.uop->op; break; default: gcc_unreachable (); } } void gfc_set_current_interface_head (gfc_interface *i) { switch (current_interface.type) { case INTERFACE_INTRINSIC_OP: current_interface.ns->op[current_interface.op] = i; break; case INTERFACE_GENERIC: current_interface.sym->generic = i; break; case INTERFACE_USER_OP: current_interface.uop->op = i; break; default: gcc_unreachable (); } } /* Gets rid of a formal argument list. We do not free symbols. Symbols are freed when a namespace is freed. */ void gfc_free_formal_arglist (gfc_formal_arglist *p) { gfc_formal_arglist *q; for (; p; p = q) { q = p->next; free (p); } } /* Check that it is ok for the typebound procedure proc to override the procedure old. */ gfc_try gfc_check_typebound_override (gfc_symtree* proc, gfc_symtree* old) { locus where; const gfc_symbol* proc_target; const gfc_symbol* old_target; unsigned proc_pass_arg, old_pass_arg, argpos; gfc_formal_arglist* proc_formal; gfc_formal_arglist* old_formal; /* This procedure should only be called for non-GENERIC proc. */ gcc_assert (!proc->n.tb->is_generic); /* If the overwritten procedure is GENERIC, this is an error. */ if (old->n.tb->is_generic) { gfc_error ("Can't overwrite GENERIC '%s' at %L", old->name, &proc->n.tb->where); return FAILURE; } where = proc->n.tb->where; proc_target = proc->n.tb->u.specific->n.sym; old_target = old->n.tb->u.specific->n.sym; /* Check that overridden binding is not NON_OVERRIDABLE. */ if (old->n.tb->non_overridable) { gfc_error ("'%s' at %L overrides a procedure binding declared" " NON_OVERRIDABLE", proc->name, &where); return FAILURE; } /* It's an error to override a non-DEFERRED procedure with a DEFERRED one. */ if (!old->n.tb->deferred && proc->n.tb->deferred) { gfc_error ("'%s' at %L must not be DEFERRED as it overrides a" " non-DEFERRED binding", proc->name, &where); return FAILURE; } /* If the overridden binding is PURE, the overriding must be, too. */ if (old_target->attr.pure && !proc_target->attr.pure) { gfc_error ("'%s' at %L overrides a PURE procedure and must also be PURE", proc->name, &where); return FAILURE; } /* If the overridden binding is ELEMENTAL, the overriding must be, too. If it is not, the overriding must not be either. */ if (old_target->attr.elemental && !proc_target->attr.elemental) { gfc_error ("'%s' at %L overrides an ELEMENTAL procedure and must also be" " ELEMENTAL", proc->name, &where); return FAILURE; } if (!old_target->attr.elemental && proc_target->attr.elemental) { gfc_error ("'%s' at %L overrides a non-ELEMENTAL procedure and must not" " be ELEMENTAL, either", proc->name, &where); return FAILURE; } /* If the overridden binding is a SUBROUTINE, the overriding must also be a SUBROUTINE. */ if (old_target->attr.subroutine && !proc_target->attr.subroutine) { gfc_error ("'%s' at %L overrides a SUBROUTINE and must also be a" " SUBROUTINE", proc->name, &where); return FAILURE; } /* If the overridden binding is a FUNCTION, the overriding must also be a FUNCTION and have the same characteristics. */ if (old_target->attr.function) { if (!proc_target->attr.function) { gfc_error ("'%s' at %L overrides a FUNCTION and must also be a" " FUNCTION", proc->name, &where); return FAILURE; } /* FIXME: Do more comprehensive checking (including, for instance, the array-shape). */ gcc_assert (proc_target->result && old_target->result); if (!compare_type_rank (proc_target->result, old_target->result)) { gfc_error ("'%s' at %L and the overridden FUNCTION should have" " matching result types and ranks", proc->name, &where); return FAILURE; } /* Check string length. */ if (proc_target->result->ts.type == BT_CHARACTER && proc_target->result->ts.u.cl && old_target->result->ts.u.cl) { int compval = gfc_dep_compare_expr (proc_target->result->ts.u.cl->length, old_target->result->ts.u.cl->length); switch (compval) { case -1: case 1: case -3: gfc_error ("Character length mismatch between '%s' at '%L' and " "overridden FUNCTION", proc->name, &where); return FAILURE; case -2: gfc_warning ("Possible character length mismatch between '%s' at" " '%L' and overridden FUNCTION", proc->name, &where); break; case 0: break; default: gfc_internal_error ("gfc_check_typebound_override: Unexpected " "result %i of gfc_dep_compare_expr", compval); break; } } } /* If the overridden binding is PUBLIC, the overriding one must not be PRIVATE. */ if (old->n.tb->access == ACCESS_PUBLIC && proc->n.tb->access == ACCESS_PRIVATE) { gfc_error ("'%s' at %L overrides a PUBLIC procedure and must not be" " PRIVATE", proc->name, &where); return FAILURE; } /* Compare the formal argument lists of both procedures. This is also abused to find the position of the passed-object dummy arguments of both bindings as at least the overridden one might not yet be resolved and we need those positions in the check below. */ proc_pass_arg = old_pass_arg = 0; if (!proc->n.tb->nopass && !proc->n.tb->pass_arg) proc_pass_arg = 1; if (!old->n.tb->nopass && !old->n.tb->pass_arg) old_pass_arg = 1; argpos = 1; for (proc_formal = proc_target->formal, old_formal = old_target->formal; proc_formal && old_formal; proc_formal = proc_formal->next, old_formal = old_formal->next) { if (proc->n.tb->pass_arg && !strcmp (proc->n.tb->pass_arg, proc_formal->sym->name)) proc_pass_arg = argpos; if (old->n.tb->pass_arg && !strcmp (old->n.tb->pass_arg, old_formal->sym->name)) old_pass_arg = argpos; /* Check that the names correspond. */ if (strcmp (proc_formal->sym->name, old_formal->sym->name)) { gfc_error ("Dummy argument '%s' of '%s' at %L should be named '%s' as" " to match the corresponding argument of the overridden" " procedure", proc_formal->sym->name, proc->name, &where, old_formal->sym->name); return FAILURE; } /* Check that the types correspond if neither is the passed-object argument. */ /* FIXME: Do more comprehensive testing here. */ if (proc_pass_arg != argpos && old_pass_arg != argpos && !gfc_compare_types (&proc_formal->sym->ts, &old_formal->sym->ts)) { gfc_error ("Types mismatch for dummy argument '%s' of '%s' %L " "in respect to the overridden procedure", proc_formal->sym->name, proc->name, &where); return FAILURE; } ++argpos; } if (proc_formal || old_formal) { gfc_error ("'%s' at %L must have the same number of formal arguments as" " the overridden procedure", proc->name, &where); return FAILURE; } /* If the overridden binding is NOPASS, the overriding one must also be NOPASS. */ if (old->n.tb->nopass && !proc->n.tb->nopass) { gfc_error ("'%s' at %L overrides a NOPASS binding and must also be" " NOPASS", proc->name, &where); return FAILURE; } /* If the overridden binding is PASS(x), the overriding one must also be PASS and the passed-object dummy arguments must correspond. */ if (!old->n.tb->nopass) { if (proc->n.tb->nopass) { gfc_error ("'%s' at %L overrides a binding with PASS and must also be" " PASS", proc->name, &where); return FAILURE; } if (proc_pass_arg != old_pass_arg) { gfc_error ("Passed-object dummy argument of '%s' at %L must be at" " the same position as the passed-object dummy argument of" " the overridden procedure", proc->name, &where); return FAILURE; } } return SUCCESS; }