/* Maintain binary trees of symbols. Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007 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 . */ #include "config.h" #include "system.h" #include "flags.h" #include "gfortran.h" #include "parse.h" /* Strings for all symbol attributes. We use these for dumping the parse tree, in error messages, and also when reading and writing modules. */ const mstring flavors[] = { minit ("UNKNOWN-FL", FL_UNKNOWN), minit ("PROGRAM", FL_PROGRAM), minit ("BLOCK-DATA", FL_BLOCK_DATA), minit ("MODULE", FL_MODULE), minit ("VARIABLE", FL_VARIABLE), minit ("PARAMETER", FL_PARAMETER), minit ("LABEL", FL_LABEL), minit ("PROCEDURE", FL_PROCEDURE), minit ("DERIVED", FL_DERIVED), minit ("NAMELIST", FL_NAMELIST), minit (NULL, -1) }; const mstring procedures[] = { minit ("UNKNOWN-PROC", PROC_UNKNOWN), minit ("MODULE-PROC", PROC_MODULE), minit ("INTERNAL-PROC", PROC_INTERNAL), minit ("DUMMY-PROC", PROC_DUMMY), minit ("INTRINSIC-PROC", PROC_INTRINSIC), minit ("EXTERNAL-PROC", PROC_EXTERNAL), minit ("STATEMENT-PROC", PROC_ST_FUNCTION), minit (NULL, -1) }; const mstring intents[] = { minit ("UNKNOWN-INTENT", INTENT_UNKNOWN), minit ("IN", INTENT_IN), minit ("OUT", INTENT_OUT), minit ("INOUT", INTENT_INOUT), minit (NULL, -1) }; const mstring access_types[] = { minit ("UNKNOWN-ACCESS", ACCESS_UNKNOWN), minit ("PUBLIC", ACCESS_PUBLIC), minit ("PRIVATE", ACCESS_PRIVATE), minit (NULL, -1) }; const mstring ifsrc_types[] = { minit ("UNKNOWN", IFSRC_UNKNOWN), minit ("DECL", IFSRC_DECL), minit ("BODY", IFSRC_IFBODY), minit ("USAGE", IFSRC_USAGE) }; const mstring save_status[] = { minit ("UNKNOWN", SAVE_NONE), minit ("EXPLICIT-SAVE", SAVE_EXPLICIT), minit ("IMPLICIT-SAVE", SAVE_IMPLICIT), }; /* This is to make sure the backend generates setup code in the correct order. */ static int next_dummy_order = 1; gfc_namespace *gfc_current_ns; gfc_gsymbol *gfc_gsym_root = NULL; static gfc_symbol *changed_syms = NULL; gfc_dt_list *gfc_derived_types; /*********** IMPLICIT NONE and IMPLICIT statement handlers ***********/ /* The following static variable indicates whether a particular element has been explicitly set or not. */ static int new_flag[GFC_LETTERS]; /* Handle a correctly parsed IMPLICIT NONE. */ void gfc_set_implicit_none (void) { int i; if (gfc_current_ns->seen_implicit_none) { gfc_error ("Duplicate IMPLICIT NONE statement at %C"); return; } gfc_current_ns->seen_implicit_none = 1; for (i = 0; i < GFC_LETTERS; i++) { gfc_clear_ts (&gfc_current_ns->default_type[i]); gfc_current_ns->set_flag[i] = 1; } } /* Reset the implicit range flags. */ void gfc_clear_new_implicit (void) { int i; for (i = 0; i < GFC_LETTERS; i++) new_flag[i] = 0; } /* Prepare for a new implicit range. Sets flags in new_flag[]. */ try gfc_add_new_implicit_range (int c1, int c2) { int i; c1 -= 'a'; c2 -= 'a'; for (i = c1; i <= c2; i++) { if (new_flag[i]) { gfc_error ("Letter '%c' already set in IMPLICIT statement at %C", i + 'A'); return FAILURE; } new_flag[i] = 1; } return SUCCESS; } /* Add a matched implicit range for gfc_set_implicit(). Check if merging the new implicit types back into the existing types will work. */ try gfc_merge_new_implicit (gfc_typespec *ts) { int i; if (gfc_current_ns->seen_implicit_none) { gfc_error ("Cannot specify IMPLICIT at %C after IMPLICIT NONE"); return FAILURE; } for (i = 0; i < GFC_LETTERS; i++) { if (new_flag[i]) { if (gfc_current_ns->set_flag[i]) { gfc_error ("Letter %c already has an IMPLICIT type at %C", i + 'A'); return FAILURE; } gfc_current_ns->default_type[i] = *ts; gfc_current_ns->set_flag[i] = 1; } } return SUCCESS; } /* Given a symbol, return a pointer to the typespec for its default type. */ gfc_typespec * gfc_get_default_type (gfc_symbol *sym, gfc_namespace *ns) { char letter; letter = sym->name[0]; if (gfc_option.flag_allow_leading_underscore && letter == '_') gfc_internal_error ("Option -fallow_leading_underscore is for use only by " "gfortran developers, and should not be used for " "implicitly typed variables"); if (letter < 'a' || letter > 'z') gfc_internal_error ("gfc_get_default_type(): Bad symbol"); if (ns == NULL) ns = gfc_current_ns; return &ns->default_type[letter - 'a']; } /* Given a pointer to a symbol, set its type according to the first letter of its name. Fails if the letter in question has no default type. */ try gfc_set_default_type (gfc_symbol *sym, int error_flag, gfc_namespace *ns) { gfc_typespec *ts; if (sym->ts.type != BT_UNKNOWN) gfc_internal_error ("gfc_set_default_type(): symbol already has a type"); ts = gfc_get_default_type (sym, ns); if (ts->type == BT_UNKNOWN) { if (error_flag && !sym->attr.untyped) { gfc_error ("Symbol '%s' at %L has no IMPLICIT type", sym->name, &sym->declared_at); sym->attr.untyped = 1; /* Ensure we only give an error once. */ } return FAILURE; } sym->ts = *ts; sym->attr.implicit_type = 1; if (sym->attr.is_bind_c == 1) { /* BIND(C) variables should not be implicitly declared. */ gfc_warning_now ("Implicitly declared BIND(C) variable '%s' at %L may " "not be C interoperable", sym->name, &sym->declared_at); sym->ts.f90_type = sym->ts.type; } if (sym->attr.dummy != 0) { if (sym->ns->proc_name != NULL && (sym->ns->proc_name->attr.subroutine != 0 || sym->ns->proc_name->attr.function != 0) && sym->ns->proc_name->attr.is_bind_c != 0) { /* Dummy args to a BIND(C) routine may not be interoperable if they are implicitly typed. */ gfc_warning_now ("Implicity declared variable '%s' at %L may not " "be C interoperable but it is a dummy argument to " "the BIND(C) procedure '%s' at %L", sym->name, &(sym->declared_at), sym->ns->proc_name->name, &(sym->ns->proc_name->declared_at)); sym->ts.f90_type = sym->ts.type; } } return SUCCESS; } /* This function is called from parse.c(parse_progunit) to check the type of the function is not implicitly typed in the host namespace and to implicitly type the function result, if necessary. */ void gfc_check_function_type (gfc_namespace *ns) { gfc_symbol *proc = ns->proc_name; if (!proc->attr.contained || proc->result->attr.implicit_type) return; if (proc->result->ts.type == BT_UNKNOWN) { if (gfc_set_default_type (proc->result, 0, gfc_current_ns) == SUCCESS) { if (proc->result != proc) { proc->ts = proc->result->ts; proc->as = gfc_copy_array_spec (proc->result->as); proc->attr.dimension = proc->result->attr.dimension; proc->attr.pointer = proc->result->attr.pointer; proc->attr.allocatable = proc->result->attr.allocatable; } } else { gfc_error ("Function result '%s' at %L has no IMPLICIT type", proc->result->name, &proc->result->declared_at); proc->result->attr.untyped = 1; } } } /******************** Symbol attribute stuff *********************/ /* This is a generic conflict-checker. We do this to avoid having a single conflict in two places. */ #define conf(a, b) if (attr->a && attr->b) { a1 = a; a2 = b; goto conflict; } #define conf2(a) if (attr->a) { a2 = a; goto conflict; } #define conf_std(a, b, std) if (attr->a && attr->b)\ {\ a1 = a;\ a2 = b;\ standard = std;\ goto conflict_std;\ } static try check_conflict (symbol_attribute *attr, const char *name, locus *where) { static const char *dummy = "DUMMY", *save = "SAVE", *pointer = "POINTER", *target = "TARGET", *external = "EXTERNAL", *intent = "INTENT", *intent_in = "INTENT(IN)", *intrinsic = "INTRINSIC", *intent_out = "INTENT(OUT)", *intent_inout = "INTENT(INOUT)", *allocatable = "ALLOCATABLE", *elemental = "ELEMENTAL", *private = "PRIVATE", *recursive = "RECURSIVE", *in_common = "COMMON", *result = "RESULT", *in_namelist = "NAMELIST", *public = "PUBLIC", *optional = "OPTIONAL", *entry = "ENTRY", *function = "FUNCTION", *subroutine = "SUBROUTINE", *dimension = "DIMENSION", *in_equivalence = "EQUIVALENCE", *use_assoc = "USE ASSOCIATED", *cray_pointer = "CRAY POINTER", *cray_pointee = "CRAY POINTEE", *data = "DATA", *value = "VALUE", *volatile_ = "VOLATILE", *protected = "PROTECTED", *is_bind_c = "BIND(C)", *procedure = "PROCEDURE"; static const char *threadprivate = "THREADPRIVATE"; const char *a1, *a2; int standard; if (where == NULL) where = &gfc_current_locus; if (attr->pointer && attr->intent != INTENT_UNKNOWN) { a1 = pointer; a2 = intent; standard = GFC_STD_F2003; goto conflict_std; } /* Check for attributes not allowed in a BLOCK DATA. */ if (gfc_current_state () == COMP_BLOCK_DATA) { a1 = NULL; if (attr->in_namelist) a1 = in_namelist; if (attr->allocatable) a1 = allocatable; if (attr->external) a1 = external; if (attr->optional) a1 = optional; if (attr->access == ACCESS_PRIVATE) a1 = private; if (attr->access == ACCESS_PUBLIC) a1 = public; if (attr->intent != INTENT_UNKNOWN) a1 = intent; if (a1 != NULL) { gfc_error ("%s attribute not allowed in BLOCK DATA program unit at %L", a1, where); return FAILURE; } } if (attr->save == SAVE_EXPLICIT) { conf (dummy, save); conf (in_common, save); conf (result, save); switch (attr->flavor) { case FL_PROGRAM: case FL_BLOCK_DATA: case FL_MODULE: case FL_LABEL: case FL_PROCEDURE: case FL_DERIVED: case FL_PARAMETER: a1 = gfc_code2string (flavors, attr->flavor); a2 = save; goto conflict; case FL_VARIABLE: case FL_NAMELIST: default: break; } } conf (dummy, entry); conf (dummy, intrinsic); conf (dummy, threadprivate); conf (pointer, target); conf (pointer, intrinsic); conf (pointer, elemental); conf (allocatable, elemental); conf (target, external); conf (target, intrinsic); conf (external, dimension); /* See Fortran 95's R504. */ conf (external, intrinsic); conf (entry, intrinsic); if ((attr->if_source && !attr->procedure) || attr->contained) { conf (external, subroutine); conf (external, function); } conf (allocatable, pointer); conf_std (allocatable, dummy, GFC_STD_F2003); conf_std (allocatable, function, GFC_STD_F2003); conf_std (allocatable, result, GFC_STD_F2003); conf (elemental, recursive); conf (in_common, dummy); conf (in_common, allocatable); conf (in_common, result); conf (dummy, result); conf (in_equivalence, use_assoc); conf (in_equivalence, dummy); conf (in_equivalence, target); conf (in_equivalence, pointer); conf (in_equivalence, function); conf (in_equivalence, result); conf (in_equivalence, entry); conf (in_equivalence, allocatable); conf (in_equivalence, threadprivate); conf (in_namelist, pointer); conf (in_namelist, allocatable); conf (entry, result); conf (function, subroutine); if (!function && !subroutine) conf (is_bind_c, dummy); conf (is_bind_c, cray_pointer); conf (is_bind_c, cray_pointee); conf (is_bind_c, allocatable); conf (is_bind_c, elemental); /* Need to also get volatile attr, according to 5.1 of F2003 draft. Parameter conflict caught below. Also, value cannot be specified for a dummy procedure. */ /* Cray pointer/pointee conflicts. */ conf (cray_pointer, cray_pointee); conf (cray_pointer, dimension); conf (cray_pointer, pointer); conf (cray_pointer, target); conf (cray_pointer, allocatable); conf (cray_pointer, external); conf (cray_pointer, intrinsic); conf (cray_pointer, in_namelist); conf (cray_pointer, function); conf (cray_pointer, subroutine); conf (cray_pointer, entry); conf (cray_pointee, allocatable); conf (cray_pointee, intent); conf (cray_pointee, optional); conf (cray_pointee, dummy); conf (cray_pointee, target); conf (cray_pointee, intrinsic); conf (cray_pointee, pointer); conf (cray_pointee, entry); conf (cray_pointee, in_common); conf (cray_pointee, in_equivalence); conf (cray_pointee, threadprivate); conf (data, dummy); conf (data, function); conf (data, result); conf (data, allocatable); conf (data, use_assoc); conf (value, pointer) conf (value, allocatable) conf (value, subroutine) conf (value, function) conf (value, volatile_) conf (value, dimension) conf (value, external) if (attr->value && (attr->intent == INTENT_OUT || attr->intent == INTENT_INOUT)) { a1 = value; a2 = attr->intent == INTENT_OUT ? intent_out : intent_inout; goto conflict; } conf (protected, intrinsic) conf (protected, external) conf (protected, in_common) conf (volatile_, intrinsic) conf (volatile_, external) if (attr->volatile_ && attr->intent == INTENT_IN) { a1 = volatile_; a2 = intent_in; goto conflict; } conf (procedure, allocatable) conf (procedure, dimension) conf (procedure, intrinsic) conf (procedure, protected) conf (procedure, target) conf (procedure, value) conf (procedure, volatile_) conf (procedure, entry) /* TODO: Implement procedure pointers. */ if (attr->procedure && attr->pointer) { gfc_error ("Fortran 2003: Procedure pointers at %L are " "not yet implemented in gfortran", where); return FAILURE; } a1 = gfc_code2string (flavors, attr->flavor); if (attr->in_namelist && attr->flavor != FL_VARIABLE && attr->flavor != FL_PROCEDURE && attr->flavor != FL_UNKNOWN) { a2 = in_namelist; goto conflict; } switch (attr->flavor) { case FL_PROGRAM: case FL_BLOCK_DATA: case FL_MODULE: case FL_LABEL: conf2 (dimension); conf2 (dummy); conf2 (volatile_); conf2 (pointer); conf2 (protected); conf2 (target); conf2 (external); conf2 (intrinsic); conf2 (allocatable); conf2 (result); conf2 (in_namelist); conf2 (optional); conf2 (function); conf2 (subroutine); conf2 (threadprivate); break; case FL_VARIABLE: case FL_NAMELIST: break; case FL_PROCEDURE: conf2 (intent); if (attr->subroutine) { conf2 (pointer); conf2 (target); conf2 (allocatable); conf2 (result); conf2 (in_namelist); conf2 (dimension); conf2 (function); conf2 (threadprivate); } switch (attr->proc) { case PROC_ST_FUNCTION: conf2 (in_common); conf2 (dummy); break; case PROC_MODULE: conf2 (dummy); break; case PROC_DUMMY: conf2 (result); conf2 (in_common); conf2 (threadprivate); break; default: break; } break; case FL_DERIVED: conf2 (dummy); conf2 (pointer); conf2 (target); conf2 (external); conf2 (intrinsic); conf2 (allocatable); conf2 (optional); conf2 (entry); conf2 (function); conf2 (subroutine); conf2 (threadprivate); if (attr->intent != INTENT_UNKNOWN) { a2 = intent; goto conflict; } break; case FL_PARAMETER: conf2 (external); conf2 (intrinsic); conf2 (optional); conf2 (allocatable); conf2 (function); conf2 (subroutine); conf2 (entry); conf2 (pointer); conf2 (protected); conf2 (target); conf2 (dummy); conf2 (in_common); conf2 (value); conf2 (volatile_); conf2 (threadprivate); conf2 (value); conf2 (is_bind_c); break; default: break; } return SUCCESS; conflict: if (name == NULL) gfc_error ("%s attribute conflicts with %s attribute at %L", a1, a2, where); else gfc_error ("%s attribute conflicts with %s attribute in '%s' at %L", a1, a2, name, where); return FAILURE; conflict_std: if (name == NULL) { return gfc_notify_std (standard, "Fortran 2003: %s attribute " "with %s attribute at %L", a1, a2, where); } else { return gfc_notify_std (standard, "Fortran 2003: %s attribute " "with %s attribute in '%s' at %L", a1, a2, name, where); } } #undef conf #undef conf2 #undef conf_std /* Mark a symbol as referenced. */ void gfc_set_sym_referenced (gfc_symbol *sym) { if (sym->attr.referenced) return; sym->attr.referenced = 1; /* Remember which order dummy variables are accessed in. */ if (sym->attr.dummy) sym->dummy_order = next_dummy_order++; } /* Common subroutine called by attribute changing subroutines in order to prevent them from changing a symbol that has been use-associated. Returns zero if it is OK to change the symbol, nonzero if not. */ static int check_used (symbol_attribute *attr, const char *name, locus *where) { if (attr->use_assoc == 0) return 0; if (where == NULL) where = &gfc_current_locus; if (name == NULL) gfc_error ("Cannot change attributes of USE-associated symbol at %L", where); else gfc_error ("Cannot change attributes of USE-associated symbol %s at %L", name, where); return 1; } /* Generate an error because of a duplicate attribute. */ static void duplicate_attr (const char *attr, locus *where) { if (where == NULL) where = &gfc_current_locus; gfc_error ("Duplicate %s attribute specified at %L", attr, where); } /* Called from decl.c (attr_decl1) to check attributes, when declared separately. */ try gfc_add_attribute (symbol_attribute *attr, locus *where) { if (check_used (attr, NULL, where)) return FAILURE; return check_conflict (attr, NULL, where); } try gfc_add_allocatable (symbol_attribute *attr, locus *where) { if (check_used (attr, NULL, where)) return FAILURE; if (attr->allocatable) { duplicate_attr ("ALLOCATABLE", where); return FAILURE; } attr->allocatable = 1; return check_conflict (attr, NULL, where); } try gfc_add_dimension (symbol_attribute *attr, const char *name, locus *where) { if (check_used (attr, name, where)) return FAILURE; if (attr->dimension) { duplicate_attr ("DIMENSION", where); return FAILURE; } attr->dimension = 1; return check_conflict (attr, name, where); } try gfc_add_external (symbol_attribute *attr, locus *where) { if (check_used (attr, NULL, where)) return FAILURE; if (attr->external) { duplicate_attr ("EXTERNAL", where); return FAILURE; } attr->external = 1; return check_conflict (attr, NULL, where); } try gfc_add_intrinsic (symbol_attribute *attr, locus *where) { if (check_used (attr, NULL, where)) return FAILURE; if (attr->intrinsic) { duplicate_attr ("INTRINSIC", where); return FAILURE; } attr->intrinsic = 1; return check_conflict (attr, NULL, where); } try gfc_add_optional (symbol_attribute *attr, locus *where) { if (check_used (attr, NULL, where)) return FAILURE; if (attr->optional) { duplicate_attr ("OPTIONAL", where); return FAILURE; } attr->optional = 1; return check_conflict (attr, NULL, where); } try gfc_add_pointer (symbol_attribute *attr, locus *where) { if (check_used (attr, NULL, where)) return FAILURE; attr->pointer = 1; return check_conflict (attr, NULL, where); } try gfc_add_cray_pointer (symbol_attribute *attr, locus *where) { if (check_used (attr, NULL, where)) return FAILURE; attr->cray_pointer = 1; return check_conflict (attr, NULL, where); } try gfc_add_cray_pointee (symbol_attribute *attr, locus *where) { if (check_used (attr, NULL, where)) return FAILURE; if (attr->cray_pointee) { gfc_error ("Cray Pointee at %L appears in multiple pointer()" " statements", where); return FAILURE; } attr->cray_pointee = 1; return check_conflict (attr, NULL, where); } try gfc_add_protected (symbol_attribute *attr, const char *name, locus *where) { if (check_used (attr, name, where)) return FAILURE; if (attr->protected) { if (gfc_notify_std (GFC_STD_LEGACY, "Duplicate PROTECTED attribute specified at %L", where) == FAILURE) return FAILURE; } attr->protected = 1; return check_conflict (attr, name, where); } try gfc_add_result (symbol_attribute *attr, const char *name, locus *where) { if (check_used (attr, name, where)) return FAILURE; attr->result = 1; return check_conflict (attr, name, where); } try gfc_add_save (symbol_attribute *attr, const char *name, locus *where) { if (check_used (attr, name, where)) return FAILURE; if (gfc_pure (NULL)) { gfc_error ("SAVE attribute at %L cannot be specified in a PURE procedure", where); return FAILURE; } if (attr->save == SAVE_EXPLICIT) { if (gfc_notify_std (GFC_STD_LEGACY, "Duplicate SAVE attribute specified at %L", where) == FAILURE) return FAILURE; } attr->save = SAVE_EXPLICIT; return check_conflict (attr, name, where); } try gfc_add_value (symbol_attribute *attr, const char *name, locus *where) { if (check_used (attr, name, where)) return FAILURE; if (attr->value) { if (gfc_notify_std (GFC_STD_LEGACY, "Duplicate VALUE attribute specified at %L", where) == FAILURE) return FAILURE; } attr->value = 1; return check_conflict (attr, name, where); } try gfc_add_volatile (symbol_attribute *attr, const char *name, locus *where) { /* No check_used needed as 11.2.1 of the F2003 standard allows that the local identifier made accessible by a use statement can be given a VOLATILE attribute. */ if (attr->volatile_ && attr->volatile_ns == gfc_current_ns) if (gfc_notify_std (GFC_STD_LEGACY, "Duplicate VOLATILE attribute specified at %L", where) == FAILURE) return FAILURE; attr->volatile_ = 1; attr->volatile_ns = gfc_current_ns; return check_conflict (attr, name, where); } try gfc_add_threadprivate (symbol_attribute *attr, const char *name, locus *where) { if (check_used (attr, name, where)) return FAILURE; if (attr->threadprivate) { duplicate_attr ("THREADPRIVATE", where); return FAILURE; } attr->threadprivate = 1; return check_conflict (attr, name, where); } try gfc_add_target (symbol_attribute *attr, locus *where) { if (check_used (attr, NULL, where)) return FAILURE; if (attr->target) { duplicate_attr ("TARGET", where); return FAILURE; } attr->target = 1; return check_conflict (attr, NULL, where); } try gfc_add_dummy (symbol_attribute *attr, const char *name, locus *where) { if (check_used (attr, name, where)) return FAILURE; /* Duplicate dummy arguments are allowed due to ENTRY statements. */ attr->dummy = 1; return check_conflict (attr, name, where); } try gfc_add_in_common (symbol_attribute *attr, const char *name, locus *where) { if (check_used (attr, name, where)) return FAILURE; /* Duplicate attribute already checked for. */ attr->in_common = 1; if (check_conflict (attr, name, where) == FAILURE) return FAILURE; if (attr->flavor == FL_VARIABLE) return SUCCESS; return gfc_add_flavor (attr, FL_VARIABLE, name, where); } try gfc_add_in_equivalence (symbol_attribute *attr, const char *name, locus *where) { /* Duplicate attribute already checked for. */ attr->in_equivalence = 1; if (check_conflict (attr, name, where) == FAILURE) return FAILURE; if (attr->flavor == FL_VARIABLE) return SUCCESS; return gfc_add_flavor (attr, FL_VARIABLE, name, where); } try gfc_add_data (symbol_attribute *attr, const char *name, locus *where) { if (check_used (attr, name, where)) return FAILURE; attr->data = 1; return check_conflict (attr, name, where); } try gfc_add_in_namelist (symbol_attribute *attr, const char *name, locus *where) { attr->in_namelist = 1; return check_conflict (attr, name, where); } try gfc_add_sequence (symbol_attribute *attr, const char *name, locus *where) { if (check_used (attr, name, where)) return FAILURE; attr->sequence = 1; return check_conflict (attr, name, where); } try gfc_add_elemental (symbol_attribute *attr, locus *where) { if (check_used (attr, NULL, where)) return FAILURE; if (attr->elemental) { duplicate_attr ("ELEMENTAL", where); return FAILURE; } attr->elemental = 1; return check_conflict (attr, NULL, where); } try gfc_add_pure (symbol_attribute *attr, locus *where) { if (check_used (attr, NULL, where)) return FAILURE; if (attr->pure) { duplicate_attr ("PURE", where); return FAILURE; } attr->pure = 1; return check_conflict (attr, NULL, where); } try gfc_add_recursive (symbol_attribute *attr, locus *where) { if (check_used (attr, NULL, where)) return FAILURE; if (attr->recursive) { duplicate_attr ("RECURSIVE", where); return FAILURE; } attr->recursive = 1; return check_conflict (attr, NULL, where); } try gfc_add_entry (symbol_attribute *attr, const char *name, locus *where) { if (check_used (attr, name, where)) return FAILURE; if (attr->entry) { duplicate_attr ("ENTRY", where); return FAILURE; } attr->entry = 1; return check_conflict (attr, name, where); } try gfc_add_function (symbol_attribute *attr, const char *name, locus *where) { if (attr->flavor != FL_PROCEDURE && gfc_add_flavor (attr, FL_PROCEDURE, name, where) == FAILURE) return FAILURE; attr->function = 1; return check_conflict (attr, name, where); } try gfc_add_subroutine (symbol_attribute *attr, const char *name, locus *where) { if (attr->flavor != FL_PROCEDURE && gfc_add_flavor (attr, FL_PROCEDURE, name, where) == FAILURE) return FAILURE; attr->subroutine = 1; return check_conflict (attr, name, where); } try gfc_add_generic (symbol_attribute *attr, const char *name, locus *where) { if (attr->flavor != FL_PROCEDURE && gfc_add_flavor (attr, FL_PROCEDURE, name, where) == FAILURE) return FAILURE; attr->generic = 1; return check_conflict (attr, name, where); } try gfc_add_proc (symbol_attribute *attr, const char *name, locus *where) { if (check_used (attr, NULL, where)) return FAILURE; if (attr->flavor != FL_PROCEDURE && gfc_add_flavor (attr, FL_PROCEDURE, name, where) == FAILURE) return FAILURE; if (attr->procedure) { duplicate_attr ("PROCEDURE", where); return FAILURE; } attr->procedure = 1; return check_conflict (attr, NULL, where); } /* Flavors are special because some flavors are not what Fortran considers attributes and can be reaffirmed multiple times. */ try gfc_add_flavor (symbol_attribute *attr, sym_flavor f, const char *name, locus *where) { if ((f == FL_PROGRAM || f == FL_BLOCK_DATA || f == FL_MODULE || f == FL_PARAMETER || f == FL_LABEL || f == FL_DERIVED || f == FL_NAMELIST) && check_used (attr, name, where)) return FAILURE; if (attr->flavor == f && f == FL_VARIABLE) return SUCCESS; if (attr->flavor != FL_UNKNOWN) { if (where == NULL) where = &gfc_current_locus; if (name) gfc_error ("%s attribute of '%s' conflicts with %s attribute at %L", gfc_code2string (flavors, attr->flavor), name, gfc_code2string (flavors, f), where); else gfc_error ("%s attribute conflicts with %s attribute at %L", gfc_code2string (flavors, attr->flavor), gfc_code2string (flavors, f), where); return FAILURE; } attr->flavor = f; return check_conflict (attr, name, where); } try gfc_add_procedure (symbol_attribute *attr, procedure_type t, const char *name, locus *where) { if (check_used (attr, name, where)) return FAILURE; if (attr->flavor != FL_PROCEDURE && gfc_add_flavor (attr, FL_PROCEDURE, name, where) == FAILURE) return FAILURE; if (where == NULL) where = &gfc_current_locus; if (attr->proc != PROC_UNKNOWN) { gfc_error ("%s procedure at %L is already declared as %s procedure", gfc_code2string (procedures, t), where, gfc_code2string (procedures, attr->proc)); return FAILURE; } attr->proc = t; /* Statement functions are always scalar and functions. */ if (t == PROC_ST_FUNCTION && ((!attr->function && gfc_add_function (attr, name, where) == FAILURE) || attr->dimension)) return FAILURE; return check_conflict (attr, name, where); } try gfc_add_intent (symbol_attribute *attr, sym_intent intent, locus *where) { if (check_used (attr, NULL, where)) return FAILURE; if (attr->intent == INTENT_UNKNOWN) { attr->intent = intent; return check_conflict (attr, NULL, where); } if (where == NULL) where = &gfc_current_locus; gfc_error ("INTENT (%s) conflicts with INTENT(%s) at %L", gfc_intent_string (attr->intent), gfc_intent_string (intent), where); return FAILURE; } /* No checks for use-association in public and private statements. */ try gfc_add_access (symbol_attribute *attr, gfc_access access, const char *name, locus *where) { if (attr->access == ACCESS_UNKNOWN) { attr->access = access; return check_conflict (attr, name, where); } if (where == NULL) where = &gfc_current_locus; gfc_error ("ACCESS specification at %L was already specified", where); return FAILURE; } /* Set the is_bind_c field for the given symbol_attribute. */ try gfc_add_is_bind_c (symbol_attribute *attr, const char *name, locus *where, int is_proc_lang_bind_spec) { if (is_proc_lang_bind_spec == 0 && attr->flavor == FL_PROCEDURE) gfc_error_now ("BIND(C) attribute at %L can only be used for " "variables or common blocks", where); else if (attr->is_bind_c) gfc_error_now ("Duplicate BIND attribute specified at %L", where); else attr->is_bind_c = 1; if (where == NULL) where = &gfc_current_locus; if (gfc_notify_std (GFC_STD_F2003, "Fortran 2003: BIND(C) at %L", where) == FAILURE) return FAILURE; return check_conflict (attr, name, where); } try gfc_add_explicit_interface (gfc_symbol *sym, ifsrc source, gfc_formal_arglist * formal, locus *where) { if (check_used (&sym->attr, sym->name, where)) return FAILURE; if (where == NULL) where = &gfc_current_locus; if (sym->attr.if_source != IFSRC_UNKNOWN && sym->attr.if_source != IFSRC_DECL) { gfc_error ("Symbol '%s' at %L already has an explicit interface", sym->name, where); return FAILURE; } sym->formal = formal; sym->attr.if_source = source; return SUCCESS; } /* Add a type to a symbol. */ try gfc_add_type (gfc_symbol *sym, gfc_typespec *ts, locus *where) { sym_flavor flavor; if (where == NULL) where = &gfc_current_locus; if (sym->ts.type != BT_UNKNOWN) { const char *msg = "Symbol '%s' at %L already has basic type of %s"; if (!(sym->ts.type == ts->type && (sym->attr.flavor == FL_PROCEDURE || sym->attr.result)) || gfc_notification_std (GFC_STD_GNU) == ERROR || pedantic) { gfc_error (msg, sym->name, where, gfc_basic_typename (sym->ts.type)); return FAILURE; } else if (gfc_notify_std (GFC_STD_GNU, msg, sym->name, where, gfc_basic_typename (sym->ts.type)) == FAILURE) return FAILURE; } flavor = sym->attr.flavor; if (flavor == FL_PROGRAM || flavor == FL_BLOCK_DATA || flavor == FL_MODULE || flavor == FL_LABEL || (flavor == FL_PROCEDURE && sym->attr.subroutine) || flavor == FL_DERIVED || flavor == FL_NAMELIST) { gfc_error ("Symbol '%s' at %L cannot have a type", sym->name, where); return FAILURE; } sym->ts = *ts; return SUCCESS; } /* Clears all attributes. */ void gfc_clear_attr (symbol_attribute *attr) { memset (attr, 0, sizeof (symbol_attribute)); } /* Check for missing attributes in the new symbol. Currently does nothing, but it's not clear that it is unnecessary yet. */ try gfc_missing_attr (symbol_attribute *attr ATTRIBUTE_UNUSED, locus *where ATTRIBUTE_UNUSED) { return SUCCESS; } /* Copy an attribute to a symbol attribute, bit by bit. Some attributes have a lot of side-effects but cannot be present given where we are called from, so we ignore some bits. */ try gfc_copy_attr (symbol_attribute *dest, symbol_attribute *src, locus *where) { int is_proc_lang_bind_spec; if (src->allocatable && gfc_add_allocatable (dest, where) == FAILURE) goto fail; if (src->dimension && gfc_add_dimension (dest, NULL, where) == FAILURE) goto fail; if (src->optional && gfc_add_optional (dest, where) == FAILURE) goto fail; if (src->pointer && gfc_add_pointer (dest, where) == FAILURE) goto fail; if (src->protected && gfc_add_protected (dest, NULL, where) == FAILURE) goto fail; if (src->save && gfc_add_save (dest, NULL, where) == FAILURE) goto fail; if (src->value && gfc_add_value (dest, NULL, where) == FAILURE) goto fail; if (src->volatile_ && gfc_add_volatile (dest, NULL, where) == FAILURE) goto fail; if (src->threadprivate && gfc_add_threadprivate (dest, NULL, where) == FAILURE) goto fail; if (src->target && gfc_add_target (dest, where) == FAILURE) goto fail; if (src->dummy && gfc_add_dummy (dest, NULL, where) == FAILURE) goto fail; if (src->result && gfc_add_result (dest, NULL, where) == FAILURE) goto fail; if (src->entry) dest->entry = 1; if (src->in_namelist && gfc_add_in_namelist (dest, NULL, where) == FAILURE) goto fail; if (src->in_common && gfc_add_in_common (dest, NULL, where) == FAILURE) goto fail; if (src->generic && gfc_add_generic (dest, NULL, where) == FAILURE) goto fail; if (src->function && gfc_add_function (dest, NULL, where) == FAILURE) goto fail; if (src->subroutine && gfc_add_subroutine (dest, NULL, where) == FAILURE) goto fail; if (src->sequence && gfc_add_sequence (dest, NULL, where) == FAILURE) goto fail; if (src->elemental && gfc_add_elemental (dest, where) == FAILURE) goto fail; if (src->pure && gfc_add_pure (dest, where) == FAILURE) goto fail; if (src->recursive && gfc_add_recursive (dest, where) == FAILURE) goto fail; if (src->flavor != FL_UNKNOWN && gfc_add_flavor (dest, src->flavor, NULL, where) == FAILURE) goto fail; if (src->intent != INTENT_UNKNOWN && gfc_add_intent (dest, src->intent, where) == FAILURE) goto fail; if (src->access != ACCESS_UNKNOWN && gfc_add_access (dest, src->access, NULL, where) == FAILURE) goto fail; if (gfc_missing_attr (dest, where) == FAILURE) goto fail; if (src->cray_pointer && gfc_add_cray_pointer (dest, where) == FAILURE) goto fail; if (src->cray_pointee && gfc_add_cray_pointee (dest, where) == FAILURE) goto fail; is_proc_lang_bind_spec = (src->flavor == FL_PROCEDURE ? 1 : 0); if (src->is_bind_c && gfc_add_is_bind_c (dest, NULL, where, is_proc_lang_bind_spec) != SUCCESS) return FAILURE; if (src->is_c_interop) dest->is_c_interop = 1; if (src->is_iso_c) dest->is_iso_c = 1; if (src->external && gfc_add_external (dest, where) == FAILURE) goto fail; if (src->intrinsic && gfc_add_intrinsic (dest, where) == FAILURE) goto fail; return SUCCESS; fail: return FAILURE; } /************** Component name management ************/ /* Component names of a derived type form their own little namespaces that are separate from all other spaces. The space is composed of a singly linked list of gfc_component structures whose head is located in the parent symbol. */ /* Add a component name to a symbol. The call fails if the name is already present. On success, the component pointer is modified to point to the additional component structure. */ try gfc_add_component (gfc_symbol *sym, const char *name, gfc_component **component) { gfc_component *p, *tail; tail = NULL; for (p = sym->components; p; p = p->next) { if (strcmp (p->name, name) == 0) { gfc_error ("Component '%s' at %C already declared at %L", name, &p->loc); return FAILURE; } tail = p; } /* Allocate a new component. */ p = gfc_get_component (); if (tail == NULL) sym->components = p; else tail->next = p; p->name = gfc_get_string (name); p->loc = gfc_current_locus; *component = p; return SUCCESS; } /* Recursive function to switch derived types of all symbol in a namespace. */ static void switch_types (gfc_symtree *st, gfc_symbol *from, gfc_symbol *to) { gfc_symbol *sym; if (st == NULL) return; sym = st->n.sym; if (sym->ts.type == BT_DERIVED && sym->ts.derived == from) sym->ts.derived = to; switch_types (st->left, from, to); switch_types (st->right, from, to); } /* This subroutine is called when a derived type is used in order to make the final determination about which version to use. The standard requires that a type be defined before it is 'used', but such types can appear in IMPLICIT statements before the actual definition. 'Using' in this context means declaring a variable to be that type or using the type constructor. If a type is used and the components haven't been defined, then we have to have a derived type in a parent unit. We find the node in the other namespace and point the symtree node in this namespace to that node. Further reference to this name point to the correct node. If we can't find the node in a parent namespace, then we have an error. This subroutine takes a pointer to a symbol node and returns a pointer to the translated node or NULL for an error. Usually there is no translation and we return the node we were passed. */ gfc_symbol * gfc_use_derived (gfc_symbol *sym) { gfc_symbol *s; gfc_typespec *t; gfc_symtree *st; int i; if (sym->components != NULL || sym->attr.zero_comp) return sym; /* Already defined. */ if (sym->ns->parent == NULL) goto bad; if (gfc_find_symbol (sym->name, sym->ns->parent, 1, &s)) { gfc_error ("Symbol '%s' at %C is ambiguous", sym->name); return NULL; } if (s == NULL || s->attr.flavor != FL_DERIVED) goto bad; /* Get rid of symbol sym, translating all references to s. */ for (i = 0; i < GFC_LETTERS; i++) { t = &sym->ns->default_type[i]; if (t->derived == sym) t->derived = s; } st = gfc_find_symtree (sym->ns->sym_root, sym->name); st->n.sym = s; s->refs++; /* Unlink from list of modified symbols. */ gfc_commit_symbol (sym); switch_types (sym->ns->sym_root, sym, s); /* TODO: Also have to replace sym -> s in other lists like namelists, common lists and interface lists. */ gfc_free_symbol (sym); return s; bad: gfc_error ("Derived type '%s' at %C is being used before it is defined", sym->name); return NULL; } /* Given a derived type node and a component name, try to locate the component structure. Returns the NULL pointer if the component is not found or the components are private. */ gfc_component * gfc_find_component (gfc_symbol *sym, const char *name) { gfc_component *p; if (name == NULL) return NULL; sym = gfc_use_derived (sym); if (sym == NULL) return NULL; for (p = sym->components; p; p = p->next) if (strcmp (p->name, name) == 0) break; if (p == NULL) gfc_error ("'%s' at %C is not a member of the '%s' structure", name, sym->name); else { if (sym->attr.use_assoc && (sym->component_access == ACCESS_PRIVATE || p->access == ACCESS_PRIVATE)) { gfc_error ("Component '%s' at %C is a PRIVATE component of '%s'", name, sym->name); p = NULL; } } return p; } /* Given a symbol, free all of the component structures and everything they point to. */ static void free_components (gfc_component *p) { gfc_component *q; for (; p; p = q) { q = p->next; gfc_free_array_spec (p->as); gfc_free_expr (p->initializer); gfc_free (p); } } /* Set component attributes from a standard symbol attribute structure. */ void gfc_set_component_attr (gfc_component *c, symbol_attribute *attr) { c->dimension = attr->dimension; c->pointer = attr->pointer; c->allocatable = attr->allocatable; c->access = attr->access; } /* Get a standard symbol attribute structure given the component structure. */ void gfc_get_component_attr (symbol_attribute *attr, gfc_component *c) { gfc_clear_attr (attr); attr->dimension = c->dimension; attr->pointer = c->pointer; attr->allocatable = c->allocatable; attr->access = c->access; } /******************** Statement label management ********************/ /* Comparison function for statement labels, used for managing the binary tree. */ static int compare_st_labels (void *a1, void *b1) { int a = ((gfc_st_label *) a1)->value; int b = ((gfc_st_label *) b1)->value; return (b - a); } /* Free a single gfc_st_label structure, making sure the tree is not messed up. This function is called only when some parse error occurs. */ void gfc_free_st_label (gfc_st_label *label) { if (label == NULL) return; gfc_delete_bbt (&gfc_current_ns->st_labels, label, compare_st_labels); if (label->format != NULL) gfc_free_expr (label->format); gfc_free (label); } /* Free a whole tree of gfc_st_label structures. */ static void free_st_labels (gfc_st_label *label) { if (label == NULL) return; free_st_labels (label->left); free_st_labels (label->right); if (label->format != NULL) gfc_free_expr (label->format); gfc_free (label); } /* Given a label number, search for and return a pointer to the label structure, creating it if it does not exist. */ gfc_st_label * gfc_get_st_label (int labelno) { gfc_st_label *lp; /* First see if the label is already in this namespace. */ lp = gfc_current_ns->st_labels; while (lp) { if (lp->value == labelno) return lp; if (lp->value < labelno) lp = lp->left; else lp = lp->right; } lp = gfc_getmem (sizeof (gfc_st_label)); lp->value = labelno; lp->defined = ST_LABEL_UNKNOWN; lp->referenced = ST_LABEL_UNKNOWN; gfc_insert_bbt (&gfc_current_ns->st_labels, lp, compare_st_labels); return lp; } /* Called when a statement with a statement label is about to be accepted. We add the label to the list of the current namespace, making sure it hasn't been defined previously and referenced correctly. */ void gfc_define_st_label (gfc_st_label *lp, gfc_sl_type type, locus *label_locus) { int labelno; labelno = lp->value; if (lp->defined != ST_LABEL_UNKNOWN) gfc_error ("Duplicate statement label %d at %L and %L", labelno, &lp->where, label_locus); else { lp->where = *label_locus; switch (type) { case ST_LABEL_FORMAT: if (lp->referenced == ST_LABEL_TARGET) gfc_error ("Label %d at %C already referenced as branch target", labelno); else lp->defined = ST_LABEL_FORMAT; break; case ST_LABEL_TARGET: if (lp->referenced == ST_LABEL_FORMAT) gfc_error ("Label %d at %C already referenced as a format label", labelno); else lp->defined = ST_LABEL_TARGET; break; default: lp->defined = ST_LABEL_BAD_TARGET; lp->referenced = ST_LABEL_BAD_TARGET; } } } /* Reference a label. Given a label and its type, see if that reference is consistent with what is known about that label, updating the unknown state. Returns FAILURE if something goes wrong. */ try gfc_reference_st_label (gfc_st_label *lp, gfc_sl_type type) { gfc_sl_type label_type; int labelno; try rc; if (lp == NULL) return SUCCESS; labelno = lp->value; if (lp->defined != ST_LABEL_UNKNOWN) label_type = lp->defined; else { label_type = lp->referenced; lp->where = gfc_current_locus; } if (label_type == ST_LABEL_FORMAT && type == ST_LABEL_TARGET) { gfc_error ("Label %d at %C previously used as a FORMAT label", labelno); rc = FAILURE; goto done; } if ((label_type == ST_LABEL_TARGET || label_type == ST_LABEL_BAD_TARGET) && type == ST_LABEL_FORMAT) { gfc_error ("Label %d at %C previously used as branch target", labelno); rc = FAILURE; goto done; } lp->referenced = type; rc = SUCCESS; done: return rc; } /*******A helper function for creating new expressions*************/ gfc_expr * gfc_lval_expr_from_sym (gfc_symbol *sym) { gfc_expr *lval; lval = gfc_get_expr (); lval->expr_type = EXPR_VARIABLE; lval->where = sym->declared_at; lval->ts = sym->ts; lval->symtree = gfc_find_symtree (sym->ns->sym_root, sym->name); /* It will always be a full array. */ lval->rank = sym->as ? sym->as->rank : 0; if (lval->rank) { lval->ref = gfc_get_ref (); lval->ref->type = REF_ARRAY; lval->ref->u.ar.type = AR_FULL; lval->ref->u.ar.dimen = lval->rank; lval->ref->u.ar.where = sym->declared_at; lval->ref->u.ar.as = sym->as; } return lval; } /************** Symbol table management subroutines ****************/ /* Basic details: Fortran 95 requires a potentially unlimited number of distinct namespaces when compiling a program unit. This case occurs during a compilation of internal subprograms because all of the internal subprograms must be read before we can start generating code for the host. Given the tricky nature of the Fortran grammar, we must be able to undo changes made to a symbol table if the current interpretation of a statement is found to be incorrect. Whenever a symbol is looked up, we make a copy of it and link to it. All of these symbols are kept in a singly linked list so that we can commit or undo the changes at a later time. A symtree may point to a symbol node outside of its namespace. In this case, that symbol has been used as a host associated variable at some previous time. */ /* Allocate a new namespace structure. Copies the implicit types from PARENT if PARENT_TYPES is set. */ gfc_namespace * gfc_get_namespace (gfc_namespace *parent, int parent_types) { gfc_namespace *ns; gfc_typespec *ts; gfc_intrinsic_op in; int i; ns = gfc_getmem (sizeof (gfc_namespace)); ns->sym_root = NULL; ns->uop_root = NULL; ns->default_access = ACCESS_UNKNOWN; ns->parent = parent; for (in = GFC_INTRINSIC_BEGIN; in != GFC_INTRINSIC_END; in++) ns->operator_access[in] = ACCESS_UNKNOWN; /* Initialize default implicit types. */ for (i = 'a'; i <= 'z'; i++) { ns->set_flag[i - 'a'] = 0; ts = &ns->default_type[i - 'a']; if (parent_types && ns->parent != NULL) { /* Copy parent settings. */ *ts = ns->parent->default_type[i - 'a']; continue; } if (gfc_option.flag_implicit_none != 0) { gfc_clear_ts (ts); continue; } if ('i' <= i && i <= 'n') { ts->type = BT_INTEGER; ts->kind = gfc_default_integer_kind; } else { ts->type = BT_REAL; ts->kind = gfc_default_real_kind; } } ns->refs = 1; return ns; } /* Comparison function for symtree nodes. */ static int compare_symtree (void *_st1, void *_st2) { gfc_symtree *st1, *st2; st1 = (gfc_symtree *) _st1; st2 = (gfc_symtree *) _st2; return strcmp (st1->name, st2->name); } /* Allocate a new symtree node and associate it with the new symbol. */ gfc_symtree * gfc_new_symtree (gfc_symtree **root, const char *name) { gfc_symtree *st; st = gfc_getmem (sizeof (gfc_symtree)); st->name = gfc_get_string (name); gfc_insert_bbt (root, st, compare_symtree); return st; } /* Delete a symbol from the tree. Does not free the symbol itself! */ static void delete_symtree (gfc_symtree **root, const char *name) { gfc_symtree st, *st0; st0 = gfc_find_symtree (*root, name); st.name = gfc_get_string (name); gfc_delete_bbt (root, &st, compare_symtree); gfc_free (st0); } /* Given a root symtree node and a name, try to find the symbol within the namespace. Returns NULL if the symbol is not found. */ gfc_symtree * gfc_find_symtree (gfc_symtree *st, const char *name) { int c; while (st != NULL) { c = strcmp (name, st->name); if (c == 0) return st; st = (c < 0) ? st->left : st->right; } return NULL; } /* Return a symtree node with a name that is guaranteed to be unique within the namespace and corresponds to an illegal fortran name. */ gfc_symtree * gfc_get_unique_symtree (gfc_namespace *ns) { char name[GFC_MAX_SYMBOL_LEN + 1]; static int serial = 0; sprintf (name, "@%d", serial++); return gfc_new_symtree (&ns->sym_root, name); } /* Given a name find a user operator node, creating it if it doesn't exist. These are much simpler than symbols because they can't be ambiguous with one another. */ gfc_user_op * gfc_get_uop (const char *name) { gfc_user_op *uop; gfc_symtree *st; st = gfc_find_symtree (gfc_current_ns->uop_root, name); if (st != NULL) return st->n.uop; st = gfc_new_symtree (&gfc_current_ns->uop_root, name); uop = st->n.uop = gfc_getmem (sizeof (gfc_user_op)); uop->name = gfc_get_string (name); uop->access = ACCESS_UNKNOWN; uop->ns = gfc_current_ns; return uop; } /* Given a name find the user operator node. Returns NULL if it does not exist. */ gfc_user_op * gfc_find_uop (const char *name, gfc_namespace *ns) { gfc_symtree *st; if (ns == NULL) ns = gfc_current_ns; st = gfc_find_symtree (ns->uop_root, name); return (st == NULL) ? NULL : st->n.uop; } /* Remove a gfc_symbol structure and everything it points to. */ void gfc_free_symbol (gfc_symbol *sym) { if (sym == NULL) return; gfc_free_array_spec (sym->as); free_components (sym->components); gfc_free_expr (sym->value); gfc_free_namelist (sym->namelist); gfc_free_namespace (sym->formal_ns); if (!sym->attr.generic_copy) gfc_free_interface (sym->generic); gfc_free_formal_arglist (sym->formal); gfc_free (sym); } /* Allocate and initialize a new symbol node. */ gfc_symbol * gfc_new_symbol (const char *name, gfc_namespace *ns) { gfc_symbol *p; p = gfc_getmem (sizeof (gfc_symbol)); gfc_clear_ts (&p->ts); gfc_clear_attr (&p->attr); p->ns = ns; p->declared_at = gfc_current_locus; if (strlen (name) > GFC_MAX_SYMBOL_LEN) gfc_internal_error ("new_symbol(): Symbol name too long"); p->name = gfc_get_string (name); /* Make sure flags for symbol being C bound are clear initially. */ p->attr.is_bind_c = 0; p->attr.is_iso_c = 0; /* Make sure the binding label field has a Nul char to start. */ p->binding_label[0] = '\0'; /* Clear the ptrs we may need. */ p->common_block = NULL; return p; } /* Generate an error if a symbol is ambiguous. */ static void ambiguous_symbol (const char *name, gfc_symtree *st) { if (st->n.sym->module) gfc_error ("Name '%s' at %C is an ambiguous reference to '%s' " "from module '%s'", name, st->n.sym->name, st->n.sym->module); else gfc_error ("Name '%s' at %C is an ambiguous reference to '%s' " "from current program unit", name, st->n.sym->name); } /* Search for a symtree starting in the current namespace, resorting to any parent namespaces if requested by a nonzero parent_flag. Returns nonzero if the name is ambiguous. */ int gfc_find_sym_tree (const char *name, gfc_namespace *ns, int parent_flag, gfc_symtree **result) { gfc_symtree *st; if (ns == NULL) ns = gfc_current_ns; do { st = gfc_find_symtree (ns->sym_root, name); if (st != NULL) { *result = st; /* Ambiguous generic interfaces are permitted, as long as the specific interfaces are different. */ if (st->ambiguous && !st->n.sym->attr.generic) { ambiguous_symbol (name, st); return 1; } return 0; } if (!parent_flag) break; ns = ns->parent; } while (ns != NULL); *result = NULL; return 0; } /* Same, but returns the symbol instead. */ int gfc_find_symbol (const char *name, gfc_namespace *ns, int parent_flag, gfc_symbol **result) { gfc_symtree *st; int i; i = gfc_find_sym_tree (name, ns, parent_flag, &st); if (st == NULL) *result = NULL; else *result = st->n.sym; return i; } /* Save symbol with the information necessary to back it out. */ static void save_symbol_data (gfc_symbol *sym) { if (sym->new || sym->old_symbol != NULL) return; sym->old_symbol = gfc_getmem (sizeof (gfc_symbol)); *(sym->old_symbol) = *sym; sym->tlink = changed_syms; changed_syms = sym; } /* Given a name, find a symbol, or create it if it does not exist yet in the current namespace. If the symbol is found we make sure that it's OK. The integer return code indicates 0 All OK 1 The symbol name was ambiguous 2 The name meant to be established was already host associated. So if the return value is nonzero, then an error was issued. */ int gfc_get_sym_tree (const char *name, gfc_namespace *ns, gfc_symtree **result) { gfc_symtree *st; gfc_symbol *p; /* This doesn't usually happen during resolution. */ if (ns == NULL) ns = gfc_current_ns; /* Try to find the symbol in ns. */ st = gfc_find_symtree (ns->sym_root, name); if (st == NULL) { /* If not there, create a new symbol. */ p = gfc_new_symbol (name, ns); /* Add to the list of tentative symbols. */ p->old_symbol = NULL; p->tlink = changed_syms; p->mark = 1; p->new = 1; changed_syms = p; st = gfc_new_symtree (&ns->sym_root, name); st->n.sym = p; p->refs++; } else { /* Make sure the existing symbol is OK. Ambiguous generic interfaces are permitted, as long as the specific interfaces are different. */ if (st->ambiguous && !st->n.sym->attr.generic) { ambiguous_symbol (name, st); return 1; } p = st->n.sym; if (p->ns != ns && (!p->attr.function || ns->proc_name != p) && !(ns->proc_name && ns->proc_name->attr.if_source == IFSRC_IFBODY && (ns->has_import_set || p->attr.imported))) { /* Symbol is from another namespace. */ gfc_error ("Symbol '%s' at %C has already been host associated", name); return 2; } p->mark = 1; /* Copy in case this symbol is changed. */ save_symbol_data (p); } *result = st; return 0; } int gfc_get_symbol (const char *name, gfc_namespace *ns, gfc_symbol **result) { gfc_symtree *st; int i; i = gfc_get_sym_tree (name, ns, &st); if (i != 0) return i; if (st) *result = st->n.sym; else *result = NULL; return i; } /* Subroutine that searches for a symbol, creating it if it doesn't exist, but tries to host-associate the symbol if possible. */ int gfc_get_ha_sym_tree (const char *name, gfc_symtree **result) { gfc_symtree *st; int i; i = gfc_find_sym_tree (name, gfc_current_ns, 0, &st); if (st != NULL) { save_symbol_data (st->n.sym); *result = st; return i; } if (gfc_current_ns->parent != NULL) { i = gfc_find_sym_tree (name, gfc_current_ns->parent, 1, &st); if (i) return i; if (st != NULL) { *result = st; return 0; } } return gfc_get_sym_tree (name, gfc_current_ns, result); } int gfc_get_ha_symbol (const char *name, gfc_symbol **result) { int i; gfc_symtree *st; i = gfc_get_ha_sym_tree (name, &st); if (st) *result = st->n.sym; else *result = NULL; return i; } /* Return true if both symbols could refer to the same data object. Does not take account of aliasing due to equivalence statements. */ int gfc_symbols_could_alias (gfc_symbol *lsym, gfc_symbol *rsym) { /* Aliasing isn't possible if the symbols have different base types. */ if (gfc_compare_types (&lsym->ts, &rsym->ts) == 0) return 0; /* Pointers can point to other pointers, target objects and allocatable objects. Two allocatable objects cannot share the same storage. */ if (lsym->attr.pointer && (rsym->attr.pointer || rsym->attr.allocatable || rsym->attr.target)) return 1; if (lsym->attr.target && rsym->attr.pointer) return 1; if (lsym->attr.allocatable && rsym->attr.pointer) return 1; return 0; } /* Undoes all the changes made to symbols in the current statement. This subroutine is made simpler due to the fact that attributes are never removed once added. */ void gfc_undo_symbols (void) { gfc_symbol *p, *q, *old; for (p = changed_syms; p; p = q) { q = p->tlink; if (p->new) { /* Symbol was new. */ delete_symtree (&p->ns->sym_root, p->name); p->refs--; if (p->refs < 0) gfc_internal_error ("gfc_undo_symbols(): Negative refs"); if (p->refs == 0) gfc_free_symbol (p); continue; } /* Restore previous state of symbol. Just copy simple stuff. */ p->mark = 0; old = p->old_symbol; p->ts.type = old->ts.type; p->ts.kind = old->ts.kind; p->attr = old->attr; if (p->value != old->value) { gfc_free_expr (old->value); p->value = NULL; } if (p->as != old->as) { if (p->as) gfc_free_array_spec (p->as); p->as = old->as; } p->generic = old->generic; p->component_access = old->component_access; if (p->namelist != NULL && old->namelist == NULL) { gfc_free_namelist (p->namelist); p->namelist = NULL; } else { if (p->namelist_tail != old->namelist_tail) { gfc_free_namelist (old->namelist_tail); old->namelist_tail->next = NULL; } } p->namelist_tail = old->namelist_tail; if (p->formal != old->formal) { gfc_free_formal_arglist (p->formal); p->formal = old->formal; } gfc_free (p->old_symbol); p->old_symbol = NULL; p->tlink = NULL; } changed_syms = NULL; } /* Free sym->old_symbol. sym->old_symbol is mostly a shallow copy of sym; the components of old_symbol that might need deallocation are the "allocatables" that are restored in gfc_undo_symbols(), with two exceptions: namelist and namelist_tail. In case these differ between old_symbol and sym, it's just because sym->namelist has gotten a few more items. */ static void free_old_symbol (gfc_symbol *sym) { if (sym->old_symbol == NULL) return; if (sym->old_symbol->as != sym->as) gfc_free_array_spec (sym->old_symbol->as); if (sym->old_symbol->value != sym->value) gfc_free_expr (sym->old_symbol->value); if (sym->old_symbol->formal != sym->formal) gfc_free_formal_arglist (sym->old_symbol->formal); gfc_free (sym->old_symbol); sym->old_symbol = NULL; } /* Makes the changes made in the current statement permanent-- gets rid of undo information. */ void gfc_commit_symbols (void) { gfc_symbol *p, *q; for (p = changed_syms; p; p = q) { q = p->tlink; p->tlink = NULL; p->mark = 0; p->new = 0; free_old_symbol (p); } changed_syms = NULL; } /* Makes the changes made in one symbol permanent -- gets rid of undo information. */ void gfc_commit_symbol (gfc_symbol *sym) { gfc_symbol *p; if (changed_syms == sym) changed_syms = sym->tlink; else { for (p = changed_syms; p; p = p->tlink) if (p->tlink == sym) { p->tlink = sym->tlink; break; } } sym->tlink = NULL; sym->mark = 0; sym->new = 0; free_old_symbol (sym); } /* Recursive function that deletes an entire tree and all the common head structures it points to. */ static void free_common_tree (gfc_symtree * common_tree) { if (common_tree == NULL) return; free_common_tree (common_tree->left); free_common_tree (common_tree->right); gfc_free (common_tree); } /* Recursive function that deletes an entire tree and all the user operator nodes that it contains. */ static void free_uop_tree (gfc_symtree *uop_tree) { if (uop_tree == NULL) return; free_uop_tree (uop_tree->left); free_uop_tree (uop_tree->right); gfc_free_interface (uop_tree->n.uop->operator); gfc_free (uop_tree->n.uop); gfc_free (uop_tree); } /* Recursive function that deletes an entire tree and all the symbols that it contains. */ static void free_sym_tree (gfc_symtree *sym_tree) { gfc_namespace *ns; gfc_symbol *sym; if (sym_tree == NULL) return; free_sym_tree (sym_tree->left); free_sym_tree (sym_tree->right); sym = sym_tree->n.sym; sym->refs--; if (sym->refs < 0) gfc_internal_error ("free_sym_tree(): Negative refs"); if (sym->formal_ns != NULL && sym->refs == 1) { /* As formal_ns contains a reference to sym, delete formal_ns just before the deletion of sym. */ ns = sym->formal_ns; sym->formal_ns = NULL; gfc_free_namespace (ns); } else if (sym->refs == 0) { /* Go ahead and delete the symbol. */ gfc_free_symbol (sym); } gfc_free (sym_tree); } /* Free the derived type list. */ static void gfc_free_dt_list (void) { gfc_dt_list *dt, *n; for (dt = gfc_derived_types; dt; dt = n) { n = dt->next; gfc_free (dt); } gfc_derived_types = NULL; } /* Free the gfc_equiv_info's. */ static void gfc_free_equiv_infos (gfc_equiv_info *s) { if (s == NULL) return; gfc_free_equiv_infos (s->next); gfc_free (s); } /* Free the gfc_equiv_lists. */ static void gfc_free_equiv_lists (gfc_equiv_list *l) { if (l == NULL) return; gfc_free_equiv_lists (l->next); gfc_free_equiv_infos (l->equiv); gfc_free (l); } /* Free a namespace structure and everything below it. Interface lists associated with intrinsic operators are not freed. These are taken care of when a specific name is freed. */ void gfc_free_namespace (gfc_namespace *ns) { gfc_charlen *cl, *cl2; gfc_namespace *p, *q; gfc_intrinsic_op i; if (ns == NULL) return; ns->refs--; if (ns->refs > 0) return; gcc_assert (ns->refs == 0); gfc_free_statements (ns->code); free_sym_tree (ns->sym_root); free_uop_tree (ns->uop_root); free_common_tree (ns->common_root); for (cl = ns->cl_list; cl; cl = cl2) { cl2 = cl->next; gfc_free_expr (cl->length); gfc_free (cl); } free_st_labels (ns->st_labels); gfc_free_equiv (ns->equiv); gfc_free_equiv_lists (ns->equiv_lists); for (i = GFC_INTRINSIC_BEGIN; i != GFC_INTRINSIC_END; i++) gfc_free_interface (ns->operator[i]); gfc_free_data (ns->data); p = ns->contained; gfc_free (ns); /* Recursively free any contained namespaces. */ while (p != NULL) { q = p; p = p->sibling; gfc_free_namespace (q); } } void gfc_symbol_init_2 (void) { gfc_current_ns = gfc_get_namespace (NULL, 0); } void gfc_symbol_done_2 (void) { gfc_free_namespace (gfc_current_ns); gfc_current_ns = NULL; gfc_free_dt_list (); } /* Clear mark bits from symbol nodes associated with a symtree node. */ static void clear_sym_mark (gfc_symtree *st) { st->n.sym->mark = 0; } /* Recursively traverse the symtree nodes. */ void gfc_traverse_symtree (gfc_symtree *st, void (*func) (gfc_symtree *)) { if (st != NULL) { (*func) (st); gfc_traverse_symtree (st->left, func); gfc_traverse_symtree (st->right, func); } } /* Recursive namespace traversal function. */ static void traverse_ns (gfc_symtree *st, void (*func) (gfc_symbol *)) { if (st == NULL) return; if (st->n.sym->mark == 0) (*func) (st->n.sym); st->n.sym->mark = 1; traverse_ns (st->left, func); traverse_ns (st->right, func); } /* Call a given function for all symbols in the namespace. We take care that each gfc_symbol node is called exactly once. */ void gfc_traverse_ns (gfc_namespace *ns, void (*func) (gfc_symbol *)) { gfc_traverse_symtree (ns->sym_root, clear_sym_mark); traverse_ns (ns->sym_root, func); } /* Return TRUE when name is the name of an intrinsic type. */ bool gfc_is_intrinsic_typename (const char *name) { if (strcmp (name, "integer") == 0 || strcmp (name, "real") == 0 || strcmp (name, "character") == 0 || strcmp (name, "logical") == 0 || strcmp (name, "complex") == 0 || strcmp (name, "doubleprecision") == 0 || strcmp (name, "doublecomplex") == 0) return true; else return false; } /* Return TRUE if the symbol is an automatic variable. */ static bool gfc_is_var_automatic (gfc_symbol *sym) { /* Pointer and allocatable variables are never automatic. */ if (sym->attr.pointer || sym->attr.allocatable) return false; /* Check for arrays with non-constant size. */ if (sym->attr.dimension && sym->as && !gfc_is_compile_time_shape (sym->as)) return true; /* Check for non-constant length character variables. */ if (sym->ts.type == BT_CHARACTER && sym->ts.cl && !gfc_is_constant_expr (sym->ts.cl->length)) return true; return false; } /* Given a symbol, mark it as SAVEd if it is allowed. */ static void save_symbol (gfc_symbol *sym) { if (sym->attr.use_assoc) return; if (sym->attr.in_common || sym->attr.dummy || sym->attr.flavor != FL_VARIABLE) return; /* Automatic objects are not saved. */ if (gfc_is_var_automatic (sym)) return; gfc_add_save (&sym->attr, sym->name, &sym->declared_at); } /* Mark those symbols which can be SAVEd as such. */ void gfc_save_all (gfc_namespace *ns) { gfc_traverse_ns (ns, save_symbol); } #ifdef GFC_DEBUG /* Make sure that no changes to symbols are pending. */ void gfc_symbol_state(void) { if (changed_syms != NULL) gfc_internal_error("Symbol changes still pending!"); } #endif /************** Global symbol handling ************/ /* Search a tree for the global symbol. */ gfc_gsymbol * gfc_find_gsymbol (gfc_gsymbol *symbol, const char *name) { int c; if (symbol == NULL) return NULL; while (symbol) { c = strcmp (name, symbol->name); if (!c) return symbol; symbol = (c < 0) ? symbol->left : symbol->right; } return NULL; } /* Compare two global symbols. Used for managing the BB tree. */ static int gsym_compare (void *_s1, void *_s2) { gfc_gsymbol *s1, *s2; s1 = (gfc_gsymbol *) _s1; s2 = (gfc_gsymbol *) _s2; return strcmp (s1->name, s2->name); } /* Get a global symbol, creating it if it doesn't exist. */ gfc_gsymbol * gfc_get_gsymbol (const char *name) { gfc_gsymbol *s; s = gfc_find_gsymbol (gfc_gsym_root, name); if (s != NULL) return s; s = gfc_getmem (sizeof (gfc_gsymbol)); s->type = GSYM_UNKNOWN; s->name = gfc_get_string (name); gfc_insert_bbt (&gfc_gsym_root, s, gsym_compare); return s; } static gfc_symbol * get_iso_c_binding_dt (int sym_id) { gfc_dt_list *dt_list; dt_list = gfc_derived_types; /* Loop through the derived types in the name list, searching for the desired symbol from iso_c_binding. Search the parent namespaces if necessary and requested to (parent_flag). */ while (dt_list != NULL) { if (dt_list->derived->from_intmod != INTMOD_NONE && dt_list->derived->intmod_sym_id == sym_id) return dt_list->derived; dt_list = dt_list->next; } return NULL; } /* Verifies that the given derived type symbol, derived_sym, is interoperable with C. This is necessary for any derived type that is BIND(C) and for derived types that are parameters to functions that are BIND(C). All fields of the derived type are required to be interoperable, and are tested for such. If an error occurs, the errors are reported here, allowing for multiple errors to be handled for a single derived type. */ try verify_bind_c_derived_type (gfc_symbol *derived_sym) { gfc_component *curr_comp = NULL; try is_c_interop = FAILURE; try retval = SUCCESS; if (derived_sym == NULL) gfc_internal_error ("verify_bind_c_derived_type(): Given symbol is " "unexpectedly NULL"); /* If we've already looked at this derived symbol, do not look at it again so we don't repeat warnings/errors. */ if (derived_sym->ts.is_c_interop) return SUCCESS; /* The derived type must have the BIND attribute to be interoperable J3/04-007, Section 15.2.3. */ if (derived_sym->attr.is_bind_c != 1) { derived_sym->ts.is_c_interop = 0; gfc_error_now ("Derived type '%s' declared at %L must have the BIND " "attribute to be C interoperable", derived_sym->name, &(derived_sym->declared_at)); retval = FAILURE; } curr_comp = derived_sym->components; /* TODO: is this really an error? */ if (curr_comp == NULL) { gfc_error ("Derived type '%s' at %L is empty", derived_sym->name, &(derived_sym->declared_at)); return FAILURE; } /* Initialize the derived type as being C interoperable. If we find an error in the components, this will be set false. */ derived_sym->ts.is_c_interop = 1; /* Loop through the list of components to verify that the kind of each is a C interoperable type. */ do { /* The components cannot be pointers (fortran sense). J3/04-007, Section 15.2.3, C1505. */ if (curr_comp->pointer != 0) { gfc_error ("Component '%s' at %L cannot have the " "POINTER attribute because it is a member " "of the BIND(C) derived type '%s' at %L", curr_comp->name, &(curr_comp->loc), derived_sym->name, &(derived_sym->declared_at)); retval = FAILURE; } /* The components cannot be allocatable. J3/04-007, Section 15.2.3, C1505. */ if (curr_comp->allocatable != 0) { gfc_error ("Component '%s' at %L cannot have the " "ALLOCATABLE attribute because it is a member " "of the BIND(C) derived type '%s' at %L", curr_comp->name, &(curr_comp->loc), derived_sym->name, &(derived_sym->declared_at)); retval = FAILURE; } /* BIND(C) derived types must have interoperable components. */ if (curr_comp->ts.type == BT_DERIVED && curr_comp->ts.derived->ts.is_iso_c != 1 && curr_comp->ts.derived != derived_sym) { /* This should be allowed; the draft says a derived-type can not have type parameters if it is has the BIND attribute. Type parameters seem to be for making parameterized derived types. There's no need to verify the type if it is c_ptr/c_funptr. */ retval = verify_bind_c_derived_type (curr_comp->ts.derived); } else { /* Grab the typespec for the given component and test the kind. */ is_c_interop = verify_c_interop (&(curr_comp->ts), curr_comp->name, &(curr_comp->loc)); if (is_c_interop != SUCCESS) { /* Report warning and continue since not fatal. The draft does specify a constraint that requires all fields to interoperate, but if the user says real(4), etc., it may interoperate with *something* in C, but the compiler most likely won't know exactly what. Further, it may not interoperate with the same data type(s) in C if the user recompiles with different flags (e.g., -m32 and -m64 on x86_64 and using integer(4) to claim interop with a C_LONG). */ if (derived_sym->attr.is_bind_c == 1) /* If the derived type is bind(c), all fields must be interop. */ gfc_warning ("Component '%s' in derived type '%s' at %L " "may not be C interoperable, even though " "derived type '%s' is BIND(C)", curr_comp->name, derived_sym->name, &(curr_comp->loc), derived_sym->name); else /* If derived type is param to bind(c) routine, or to one of the iso_c_binding procs, it must be interoperable, so all fields must interop too. */ gfc_warning ("Component '%s' in derived type '%s' at %L " "may not be C interoperable", curr_comp->name, derived_sym->name, &(curr_comp->loc)); } } curr_comp = curr_comp->next; } while (curr_comp != NULL); /* Make sure we don't have conflicts with the attributes. */ if (derived_sym->attr.access == ACCESS_PRIVATE) { gfc_error ("Derived type '%s' at %L cannot be declared with both " "PRIVATE and BIND(C) attributes", derived_sym->name, &(derived_sym->declared_at)); retval = FAILURE; } if (derived_sym->attr.sequence != 0) { gfc_error ("Derived type '%s' at %L cannot have the SEQUENCE " "attribute because it is BIND(C)", derived_sym->name, &(derived_sym->declared_at)); retval = FAILURE; } /* Mark the derived type as not being C interoperable if we found an error. If there were only warnings, proceed with the assumption it's interoperable. */ if (retval == FAILURE) derived_sym->ts.is_c_interop = 0; return retval; } /* Generate symbols for the named constants c_null_ptr and c_null_funptr. */ static try gen_special_c_interop_ptr (int ptr_id, const char *ptr_name, const char *module_name) { gfc_symtree *tmp_symtree; gfc_symbol *tmp_sym; tmp_symtree = gfc_find_symtree (gfc_current_ns->sym_root, ptr_name); if (tmp_symtree != NULL) tmp_sym = tmp_symtree->n.sym; else { tmp_sym = NULL; gfc_internal_error ("gen_special_c_interop_ptr(): Unable to " "create symbol for %s", ptr_name); } /* Set up the symbol's important fields. Save attr required so we can initialize the ptr to NULL. */ tmp_sym->attr.save = SAVE_EXPLICIT; tmp_sym->ts.is_c_interop = 1; tmp_sym->attr.is_c_interop = 1; tmp_sym->ts.is_iso_c = 1; tmp_sym->ts.type = BT_DERIVED; /* The c_ptr and c_funptr derived types will provide the definition for c_null_ptr and c_null_funptr, respectively. */ if (ptr_id == ISOCBINDING_NULL_PTR) tmp_sym->ts.derived = get_iso_c_binding_dt (ISOCBINDING_PTR); else tmp_sym->ts.derived = get_iso_c_binding_dt (ISOCBINDING_FUNPTR); if (tmp_sym->ts.derived == NULL) { /* This can occur if the user forgot to declare c_ptr or c_funptr and they're trying to use one of the procedures that has arg(s) of the missing type. In this case, a regular version of the thing should have been put in the current ns. */ generate_isocbinding_symbol (module_name, ptr_id == ISOCBINDING_NULL_PTR ? ISOCBINDING_PTR : ISOCBINDING_FUNPTR, (const char *) (ptr_id == ISOCBINDING_NULL_PTR ? "_gfortran_iso_c_binding_c_ptr" : "_gfortran_iso_c_binding_c_funptr")); tmp_sym->ts.derived = get_iso_c_binding_dt (ptr_id == ISOCBINDING_NULL_PTR ? ISOCBINDING_PTR : ISOCBINDING_FUNPTR); } /* Module name is some mangled version of iso_c_binding. */ tmp_sym->module = gfc_get_string (module_name); /* Say it's from the iso_c_binding module. */ tmp_sym->attr.is_iso_c = 1; tmp_sym->attr.use_assoc = 1; tmp_sym->attr.is_bind_c = 1; /* Set the binding_label. */ sprintf (tmp_sym->binding_label, "%s_%s", module_name, tmp_sym->name); /* Set the c_address field of c_null_ptr and c_null_funptr to the value of NULL. */ tmp_sym->value = gfc_get_expr (); tmp_sym->value->expr_type = EXPR_STRUCTURE; tmp_sym->value->ts.type = BT_DERIVED; tmp_sym->value->ts.derived = tmp_sym->ts.derived; tmp_sym->value->value.constructor = gfc_get_constructor (); /* This line will initialize the c_null_ptr/c_null_funptr c_address field to NULL. */ tmp_sym->value->value.constructor->expr = gfc_int_expr (0); /* Must declare c_null_ptr and c_null_funptr as having the PARAMETER attribute so they can be used in init expressions. */ tmp_sym->attr.flavor = FL_PARAMETER; return SUCCESS; } /* Add a formal argument, gfc_formal_arglist, to the end of the given list of arguments. Set the reference to the provided symbol, param_sym, in the argument. */ static void add_formal_arg (gfc_formal_arglist **head, gfc_formal_arglist **tail, gfc_formal_arglist *formal_arg, gfc_symbol *param_sym) { /* Put in list, either as first arg or at the tail (curr arg). */ if (*head == NULL) *head = *tail = formal_arg; else { (*tail)->next = formal_arg; (*tail) = formal_arg; } (*tail)->sym = param_sym; (*tail)->next = NULL; return; } /* Generates a symbol representing the CPTR argument to an iso_c_binding procedure. Also, create a gfc_formal_arglist for the CPTR and add it to the provided argument list. */ static void gen_cptr_param (gfc_formal_arglist **head, gfc_formal_arglist **tail, const char *module_name, gfc_namespace *ns, const char *c_ptr_name, int iso_c_sym_id) { gfc_symbol *param_sym = NULL; gfc_symbol *c_ptr_sym = NULL; gfc_symtree *param_symtree = NULL; gfc_formal_arglist *formal_arg = NULL; const char *c_ptr_in; const char *c_ptr_type = NULL; if (iso_c_sym_id == ISOCBINDING_F_PROCPOINTER) c_ptr_type = "_gfortran_iso_c_binding_c_funptr"; else c_ptr_type = "_gfortran_iso_c_binding_c_ptr"; if(c_ptr_name == NULL) c_ptr_in = "gfc_cptr__"; else c_ptr_in = c_ptr_name; gfc_get_sym_tree (c_ptr_in, ns, ¶m_symtree); if (param_symtree != NULL) param_sym = param_symtree->n.sym; else gfc_internal_error ("gen_cptr_param(): Unable to " "create symbol for %s", c_ptr_in); /* Set up the appropriate fields for the new c_ptr param sym. */ param_sym->refs++; param_sym->attr.flavor = FL_DERIVED; param_sym->ts.type = BT_DERIVED; param_sym->attr.intent = INTENT_IN; param_sym->attr.dummy = 1; /* This will pass the ptr to the iso_c routines as a (void *). */ param_sym->attr.value = 1; param_sym->attr.use_assoc = 1; /* Get the symbol for c_ptr or c_funptr, no matter what it's name is (user renamed). */ if (iso_c_sym_id == ISOCBINDING_F_PROCPOINTER) c_ptr_sym = get_iso_c_binding_dt (ISOCBINDING_FUNPTR); else c_ptr_sym = get_iso_c_binding_dt (ISOCBINDING_PTR); if (c_ptr_sym == NULL) { /* This can happen if the user did not define c_ptr but they are trying to use one of the iso_c_binding functions that need it. */ if (iso_c_sym_id == ISOCBINDING_F_PROCPOINTER) generate_isocbinding_symbol (module_name, ISOCBINDING_FUNPTR, (const char *)c_ptr_type); else generate_isocbinding_symbol (module_name, ISOCBINDING_PTR, (const char *)c_ptr_type); gfc_get_ha_symbol (c_ptr_type, &(c_ptr_sym)); } param_sym->ts.derived = c_ptr_sym; param_sym->module = gfc_get_string (module_name); /* Make new formal arg. */ formal_arg = gfc_get_formal_arglist (); /* Add arg to list of formal args (the CPTR arg). */ add_formal_arg (head, tail, formal_arg, param_sym); } /* Generates a symbol representing the FPTR argument to an iso_c_binding procedure. Also, create a gfc_formal_arglist for the FPTR and add it to the provided argument list. */ static void gen_fptr_param (gfc_formal_arglist **head, gfc_formal_arglist **tail, const char *module_name, gfc_namespace *ns, const char *f_ptr_name) { gfc_symbol *param_sym = NULL; gfc_symtree *param_symtree = NULL; gfc_formal_arglist *formal_arg = NULL; const char *f_ptr_out = "gfc_fptr__"; if (f_ptr_name != NULL) f_ptr_out = f_ptr_name; gfc_get_sym_tree (f_ptr_out, ns, ¶m_symtree); if (param_symtree != NULL) param_sym = param_symtree->n.sym; else gfc_internal_error ("generateFPtrParam(): Unable to " "create symbol for %s", f_ptr_out); /* Set up the necessary fields for the fptr output param sym. */ param_sym->refs++; param_sym->attr.pointer = 1; param_sym->attr.dummy = 1; param_sym->attr.use_assoc = 1; /* ISO C Binding type to allow any pointer type as actual param. */ param_sym->ts.type = BT_VOID; param_sym->module = gfc_get_string (module_name); /* Make the arg. */ formal_arg = gfc_get_formal_arglist (); /* Add arg to list of formal args. */ add_formal_arg (head, tail, formal_arg, param_sym); } /* Generates a symbol representing the optional SHAPE argument for the iso_c_binding c_f_pointer() procedure. Also, create a gfc_formal_arglist for the SHAPE and add it to the provided argument list. */ static void gen_shape_param (gfc_formal_arglist **head, gfc_formal_arglist **tail, const char *module_name, gfc_namespace *ns, const char *shape_param_name) { gfc_symbol *param_sym = NULL; gfc_symtree *param_symtree = NULL; gfc_formal_arglist *formal_arg = NULL; const char *shape_param = "gfc_shape_array__"; int i; if (shape_param_name != NULL) shape_param = shape_param_name; gfc_get_sym_tree (shape_param, ns, ¶m_symtree); if (param_symtree != NULL) param_sym = param_symtree->n.sym; else gfc_internal_error ("generateShapeParam(): Unable to " "create symbol for %s", shape_param); /* Set up the necessary fields for the shape input param sym. */ param_sym->refs++; param_sym->attr.dummy = 1; param_sym->attr.use_assoc = 1; /* Integer array, rank 1, describing the shape of the object. Make it's type BT_VOID initially so we can accept any type/kind combination of integer. During gfc_iso_c_sub_interface (resolve.c), we'll make it of BT_INTEGER type. */ param_sym->ts.type = BT_VOID; /* Initialize the kind to default integer. However, it will be overridden during resolution to match the kind of the SHAPE parameter given as the actual argument (to allow for any valid integer kind). */ param_sym->ts.kind = gfc_default_integer_kind; param_sym->as = gfc_get_array_spec (); /* Clear out the dimension info for the array. */ for (i = 0; i < GFC_MAX_DIMENSIONS; i++) { param_sym->as->lower[i] = NULL; param_sym->as->upper[i] = NULL; } param_sym->as->rank = 1; param_sym->as->lower[0] = gfc_int_expr (1); /* The extent is unknown until we get it. The length give us the rank the incoming pointer. */ param_sym->as->type = AS_ASSUMED_SHAPE; /* The arg is also optional; it is required iff the second arg (fptr) is to an array, otherwise, it's ignored. */ param_sym->attr.optional = 1; param_sym->attr.intent = INTENT_IN; param_sym->attr.dimension = 1; param_sym->module = gfc_get_string (module_name); /* Make the arg. */ formal_arg = gfc_get_formal_arglist (); /* Add arg to list of formal args. */ add_formal_arg (head, tail, formal_arg, param_sym); } /* Add a procedure interface to the given symbol (i.e., store a reference to the list of formal arguments). */ static void add_proc_interface (gfc_symbol *sym, ifsrc source, gfc_formal_arglist *formal) { sym->formal = formal; sym->attr.if_source = source; } /* Copy the formal args from an existing symbol, src, into a new symbol, dest. New formal args are created, and the description of each arg is set according to the existing ones. This function is used when creating procedure declaration variables from a procedure declaration statement (see match_proc_decl()) to create the formal args based on the args of a given named interface. */ void copy_formal_args (gfc_symbol *dest, gfc_symbol *src) { gfc_formal_arglist *head = NULL; gfc_formal_arglist *tail = NULL; gfc_formal_arglist *formal_arg = NULL; gfc_formal_arglist *curr_arg = NULL; gfc_formal_arglist *formal_prev = NULL; /* Save current namespace so we can change it for formal args. */ gfc_namespace *parent_ns = gfc_current_ns; /* Create a new namespace, which will be the formal ns (namespace of the formal args). */ gfc_current_ns = gfc_get_namespace (parent_ns, 0); gfc_current_ns->proc_name = dest; for (curr_arg = src->formal; curr_arg; curr_arg = curr_arg->next) { formal_arg = gfc_get_formal_arglist (); gfc_get_symbol (curr_arg->sym->name, gfc_current_ns, &(formal_arg->sym)); /* May need to copy more info for the symbol. */ formal_arg->sym->attr = curr_arg->sym->attr; formal_arg->sym->ts = curr_arg->sym->ts; /* If this isn't the first arg, set up the next ptr. For the last arg built, the formal_arg->next will never get set to anything other than NULL. */ if (formal_prev != NULL) formal_prev->next = formal_arg; else formal_arg->next = NULL; formal_prev = formal_arg; /* Add arg to list of formal args. */ add_formal_arg (&head, &tail, formal_arg, formal_arg->sym); } /* Add the interface to the symbol. */ add_proc_interface (dest, IFSRC_DECL, head); /* Store the formal namespace information. */ if (dest->formal != NULL) /* The current ns should be that for the dest proc. */ dest->formal_ns = gfc_current_ns; /* Restore the current namespace to what it was on entry. */ gfc_current_ns = parent_ns; } /* Builds the parameter list for the iso_c_binding procedure c_f_pointer or c_f_procpointer. The old_sym typically refers to a generic version of either the c_f_pointer or c_f_procpointer functions. The new_proc_sym represents a "resolved" version of the symbol. The functions are resolved to match the types of their parameters; for example, c_f_pointer(cptr, fptr) would resolve to something similar to c_f_pointer_i4 if the type of data object fptr pointed to was a default integer. The actual name of the resolved procedure symbol is further mangled with the module name, etc., but the idea holds true. */ static void build_formal_args (gfc_symbol *new_proc_sym, gfc_symbol *old_sym, int add_optional_arg) { gfc_formal_arglist *head = NULL, *tail = NULL; gfc_namespace *parent_ns = NULL; parent_ns = gfc_current_ns; /* Create a new namespace, which will be the formal ns (namespace of the formal args). */ gfc_current_ns = gfc_get_namespace(parent_ns, 0); gfc_current_ns->proc_name = new_proc_sym; /* Generate the params. */ if ((old_sym->intmod_sym_id == ISOCBINDING_F_POINTER) || (old_sym->intmod_sym_id == ISOCBINDING_F_PROCPOINTER)) { gen_cptr_param (&head, &tail, (const char *) new_proc_sym->module, gfc_current_ns, "cptr", old_sym->intmod_sym_id); gen_fptr_param (&head, &tail, (const char *) new_proc_sym->module, gfc_current_ns, "fptr"); /* If we're dealing with c_f_pointer, it has an optional third arg. */ if (old_sym->intmod_sym_id == ISOCBINDING_F_POINTER) { gen_shape_param (&head, &tail, (const char *) new_proc_sym->module, gfc_current_ns, "shape"); } } else if (old_sym->intmod_sym_id == ISOCBINDING_ASSOCIATED) { /* c_associated has one required arg and one optional; both are c_ptrs. */ gen_cptr_param (&head, &tail, (const char *) new_proc_sym->module, gfc_current_ns, "c_ptr_1", ISOCBINDING_ASSOCIATED); if (add_optional_arg) { gen_cptr_param (&head, &tail, (const char *) new_proc_sym->module, gfc_current_ns, "c_ptr_2", ISOCBINDING_ASSOCIATED); /* The last param is optional so mark it as such. */ tail->sym->attr.optional = 1; } } /* Add the interface (store formal args to new_proc_sym). */ add_proc_interface (new_proc_sym, IFSRC_DECL, head); /* Set up the formal_ns pointer to the one created for the new procedure so it'll get cleaned up during gfc_free_symbol(). */ new_proc_sym->formal_ns = gfc_current_ns; gfc_current_ns = parent_ns; } /* Generate the given set of C interoperable kind objects, or all interoperable kinds. This function will only be given kind objects for valid iso_c_binding defined types because this is verified when the 'use' statement is parsed. If the user gives an 'only' clause, the specific kinds are looked up; if they don't exist, an error is reported. If the user does not give an 'only' clause, all iso_c_binding symbols are generated. If a list of specific kinds is given, it must have a NULL in the first empty spot to mark the end of the list. */ void generate_isocbinding_symbol (const char *mod_name, iso_c_binding_symbol s, const char *local_name) { const char *const name = (local_name && local_name[0]) ? local_name : c_interop_kinds_table[s].name; gfc_symtree *tmp_symtree = NULL; gfc_symbol *tmp_sym = NULL; gfc_dt_list **dt_list_ptr = NULL; gfc_component *tmp_comp = NULL; char comp_name[(GFC_MAX_SYMBOL_LEN * 2) + 1]; int index; tmp_symtree = gfc_find_symtree (gfc_current_ns->sym_root, name); /* Already exists in this scope so don't re-add it. TODO: we should probably check that it's really the same symbol. */ if (tmp_symtree != NULL) return; /* Create the sym tree in the current ns. */ gfc_get_sym_tree (name, gfc_current_ns, &tmp_symtree); if (tmp_symtree) tmp_sym = tmp_symtree->n.sym; else gfc_internal_error ("generate_isocbinding_symbol(): Unable to " "create symbol"); /* Say what module this symbol belongs to. */ tmp_sym->module = gfc_get_string (mod_name); tmp_sym->from_intmod = INTMOD_ISO_C_BINDING; tmp_sym->intmod_sym_id = s; switch (s) { #define NAMED_INTCST(a,b,c) case a : #define NAMED_REALCST(a,b,c) case a : #define NAMED_CMPXCST(a,b,c) case a : #define NAMED_LOGCST(a,b,c) case a : #define NAMED_CHARKNDCST(a,b,c) case a : #include "iso-c-binding.def" tmp_sym->value = gfc_int_expr (c_interop_kinds_table[s].value); /* Initialize an integer constant expression node. */ tmp_sym->attr.flavor = FL_PARAMETER; tmp_sym->ts.type = BT_INTEGER; tmp_sym->ts.kind = gfc_default_integer_kind; /* Mark this type as a C interoperable one. */ tmp_sym->ts.is_c_interop = 1; tmp_sym->ts.is_iso_c = 1; tmp_sym->value->ts.is_c_interop = 1; tmp_sym->value->ts.is_iso_c = 1; tmp_sym->attr.is_c_interop = 1; /* Tell what f90 type this c interop kind is valid. */ tmp_sym->ts.f90_type = c_interop_kinds_table[s].f90_type; /* Say it's from the iso_c_binding module. */ tmp_sym->attr.is_iso_c = 1; /* Make it use associated. */ tmp_sym->attr.use_assoc = 1; break; #define NAMED_CHARCST(a,b,c) case a : #include "iso-c-binding.def" /* Initialize an integer constant expression node for the length of the character. */ tmp_sym->value = gfc_get_expr (); tmp_sym->value->expr_type = EXPR_CONSTANT; tmp_sym->value->ts.type = BT_CHARACTER; tmp_sym->value->ts.kind = gfc_default_character_kind; tmp_sym->value->where = gfc_current_locus; tmp_sym->value->ts.is_c_interop = 1; tmp_sym->value->ts.is_iso_c = 1; tmp_sym->value->value.character.length = 1; tmp_sym->value->value.character.string = gfc_getmem (2); tmp_sym->value->value.character.string[0] = (char) c_interop_kinds_table[s].value; tmp_sym->value->value.character.string[1] = '\0'; /* May not need this in both attr and ts, but do need in attr for writing module file. */ tmp_sym->attr.is_c_interop = 1; tmp_sym->attr.flavor = FL_PARAMETER; tmp_sym->ts.type = BT_CHARACTER; /* Need to set it to the C_CHAR kind. */ tmp_sym->ts.kind = gfc_default_character_kind; /* Mark this type as a C interoperable one. */ tmp_sym->ts.is_c_interop = 1; tmp_sym->ts.is_iso_c = 1; /* Tell what f90 type this c interop kind is valid. */ tmp_sym->ts.f90_type = BT_CHARACTER; /* Say it's from the iso_c_binding module. */ tmp_sym->attr.is_iso_c = 1; /* Make it use associated. */ tmp_sym->attr.use_assoc = 1; break; case ISOCBINDING_PTR: case ISOCBINDING_FUNPTR: /* Initialize an integer constant expression node. */ tmp_sym->attr.flavor = FL_DERIVED; tmp_sym->ts.is_c_interop = 1; tmp_sym->attr.is_c_interop = 1; tmp_sym->attr.is_iso_c = 1; tmp_sym->ts.is_iso_c = 1; tmp_sym->ts.type = BT_DERIVED; /* A derived type must have the bind attribute to be interoperable (J3/04-007, Section 15.2.3), even though the binding label is not used. */ tmp_sym->attr.is_bind_c = 1; tmp_sym->attr.referenced = 1; tmp_sym->ts.derived = tmp_sym; /* Add the symbol created for the derived type to the current ns. */ dt_list_ptr = &(gfc_derived_types); while (*dt_list_ptr != NULL && (*dt_list_ptr)->next != NULL) dt_list_ptr = &((*dt_list_ptr)->next); /* There is already at least one derived type in the list, so append the one we're currently building for c_ptr or c_funptr. */ if (*dt_list_ptr != NULL) dt_list_ptr = &((*dt_list_ptr)->next); (*dt_list_ptr) = gfc_get_dt_list (); (*dt_list_ptr)->derived = tmp_sym; (*dt_list_ptr)->next = NULL; /* Set up the component of the derived type, which will be an integer with kind equal to c_ptr_size. Mangle the name of the field for the c_address to prevent the curious user from trying to access it from Fortran. */ sprintf (comp_name, "__%s_%s", tmp_sym->name, "c_address"); gfc_add_component (tmp_sym, comp_name, &tmp_comp); if (tmp_comp == NULL) gfc_internal_error ("generate_isocbinding_symbol(): Unable to " "create component for c_address"); tmp_comp->ts.type = BT_INTEGER; /* Set this because the module will need to read/write this field. */ tmp_comp->ts.f90_type = BT_INTEGER; /* The kinds for c_ptr and c_funptr are the same. */ index = get_c_kind ("c_ptr", c_interop_kinds_table); tmp_comp->ts.kind = c_interop_kinds_table[index].value; tmp_comp->pointer = 0; tmp_comp->dimension = 0; /* Mark the component as C interoperable. */ tmp_comp->ts.is_c_interop = 1; /* Make it use associated (iso_c_binding module). */ tmp_sym->attr.use_assoc = 1; break; case ISOCBINDING_NULL_PTR: case ISOCBINDING_NULL_FUNPTR: gen_special_c_interop_ptr (s, name, mod_name); break; case ISOCBINDING_F_POINTER: case ISOCBINDING_ASSOCIATED: case ISOCBINDING_LOC: case ISOCBINDING_FUNLOC: case ISOCBINDING_F_PROCPOINTER: tmp_sym->attr.proc = PROC_MODULE; /* Use the procedure's name as it is in the iso_c_binding module for setting the binding label in case the user renamed the symbol. */ sprintf (tmp_sym->binding_label, "%s_%s", mod_name, c_interop_kinds_table[s].name); tmp_sym->attr.is_iso_c = 1; if (s == ISOCBINDING_F_POINTER || s == ISOCBINDING_F_PROCPOINTER) tmp_sym->attr.subroutine = 1; else { /* TODO! This needs to be finished more for the expr of the function or something! This may not need to be here, because trying to do c_loc as an external. */ if (s == ISOCBINDING_ASSOCIATED) { tmp_sym->attr.function = 1; tmp_sym->ts.type = BT_LOGICAL; tmp_sym->ts.kind = gfc_default_logical_kind; tmp_sym->result = tmp_sym; } else { /* Here, we're taking the simple approach. We're defining c_loc as an external identifier so the compiler will put what we expect on the stack for the address we want the C address of. */ tmp_sym->ts.type = BT_DERIVED; if (s == ISOCBINDING_LOC) tmp_sym->ts.derived = get_iso_c_binding_dt (ISOCBINDING_PTR); else tmp_sym->ts.derived = get_iso_c_binding_dt (ISOCBINDING_FUNPTR); if (tmp_sym->ts.derived == NULL) { /* Create the necessary derived type so we can continue processing the file. */ generate_isocbinding_symbol (mod_name, s == ISOCBINDING_FUNLOC ? ISOCBINDING_FUNPTR : ISOCBINDING_PTR, (const char *)(s == ISOCBINDING_FUNLOC ? "_gfortran_iso_c_binding_c_funptr" : "_gfortran_iso_c_binding_c_ptr")); tmp_sym->ts.derived = get_iso_c_binding_dt (s == ISOCBINDING_FUNLOC ? ISOCBINDING_FUNPTR : ISOCBINDING_PTR); } /* The function result is itself (no result clause). */ tmp_sym->result = tmp_sym; tmp_sym->attr.external = 1; tmp_sym->attr.use_assoc = 0; tmp_sym->attr.if_source = IFSRC_UNKNOWN; tmp_sym->attr.proc = PROC_UNKNOWN; } } tmp_sym->attr.flavor = FL_PROCEDURE; tmp_sym->attr.contained = 0; /* Try using this builder routine, with the new and old symbols both being the generic iso_c proc sym being created. This will create the formal args (and the new namespace for them). Don't build an arg list for c_loc because we're going to treat c_loc as an external procedure. */ if (s != ISOCBINDING_LOC && s != ISOCBINDING_FUNLOC) /* The 1 says to add any optional args, if applicable. */ build_formal_args (tmp_sym, tmp_sym, 1); /* Set this after setting up the symbol, to prevent error messages. */ tmp_sym->attr.use_assoc = 1; /* This symbol will not be referenced directly. It will be resolved to the implementation for the given f90 kind. */ tmp_sym->attr.referenced = 0; break; default: gcc_unreachable (); } } /* Creates a new symbol based off of an old iso_c symbol, with a new binding label. This function can be used to create a new, resolved, version of a procedure symbol for c_f_pointer or c_f_procpointer that is based on the generic symbols. A new parameter list is created for the new symbol using build_formal_args(). The add_optional_flag specifies whether the to add the optional SHAPE argument. The new symbol is returned. */ gfc_symbol * get_iso_c_sym (gfc_symbol *old_sym, char *new_name, char *new_binding_label, int add_optional_arg) { gfc_symtree *new_symtree = NULL; /* See if we have a symbol by that name already available, looking through any parent namespaces. */ gfc_find_sym_tree (new_name, gfc_current_ns, 1, &new_symtree); if (new_symtree != NULL) /* Return the existing symbol. */ return new_symtree->n.sym; /* Create the symtree/symbol, with attempted host association. */ gfc_get_ha_sym_tree (new_name, &new_symtree); if (new_symtree == NULL) gfc_internal_error ("get_iso_c_sym(): Unable to create " "symtree for '%s'", new_name); /* Now fill in the fields of the resolved symbol with the old sym. */ strcpy (new_symtree->n.sym->binding_label, new_binding_label); new_symtree->n.sym->attr = old_sym->attr; new_symtree->n.sym->ts = old_sym->ts; new_symtree->n.sym->module = gfc_get_string (old_sym->module); /* Build the formal arg list. */ build_formal_args (new_symtree->n.sym, old_sym, add_optional_arg); gfc_commit_symbol (new_symtree->n.sym); return new_symtree->n.sym; }