Fixed __SET_EXTERNAL_FB declaration in accessor.h, invoked when accessing EXTERNAL_BLOCK.VARIABLE. Macro was invoking __SET_VAR with wrong parameter count. Fixed corresponding code generator for ST. Seems similar codegen for IL is also broken, but fix would affect other (unknown) behviours -> didn't touch it.
/*
* matiec - a compiler for the programming languages defined in IEC 61131-3
*
* Copyright (C) 2003-2011 Mario de Sousa (msousa@fe.up.pt)
* Copyright (C) 2007-2011 Laurent Bessard and Edouard Tisserant
*
* This program 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 of the License, or
* (at your option) any later version.
*
* This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
*
*
* This code is made available on the understanding that it will not be
* used in safety-critical situations without a full and competent review.
*/
/*
* An IEC 61131-3 compiler.
*
* Based on the
* FINAL DRAFT - IEC 61131-3, 2nd Ed. (2001-12-10)
*
*/
/*
* Function parameter iterator.
* Iterate through the in/out parameters of a function declaration.
* Function blocks are also suported.
*
* This is part of the 4th stage that generates
* a c++ source program equivalent to the IL and ST
* code.
*/
/* Given a function_declaration_c, iterate through each
* function in/out/inout parameter, returning the name
* of each parameter...function_param_iterator_c
*/
#include "function_param_iterator.hh" /* no longer required, aready included by absyntax_utils.hh */
#include "spec_init_separator.hh" /* no longer required, aready included by absyntax_utils.hh */
#include <stdlib.h> /* required for strtol() */
#include <string.h>
#include <strings.h>
#include <limits> // required for std::numeric_limits< XXX >::max()
#include <errno.h> // required for errno
#include "../main.hh" // required for ERROR() and ERROR_MSG() macros.
//#define DEBUG
#ifdef DEBUG
#define TRACE(classname) printf("\n____%s____\n",classname);
#else
#define TRACE(classname)
#endif
/* NOTE: The following function is not really needed, as we could get the value that constant_folding_c determined for this
* integer. Remember that currently constant_folding_c runs before this class is ever used/called!
* However, I (Mario) do not currently feel it would be a good idea to restrict the use of this
* abstract syntax utility to only after the constant_folding_c has had a chance to fill in the constant value
* of this symbol.
* For this reason only, I have opted to let this abstract syntax utility have its own private copy of the
* extract_integer() function.
* Another aspect that makes this OK is that this function will only be used to extract the integer value of the
* index for the first extensible paramater (examples follow shortly). Since this is an extension to IEC 61131-3
* that we created to allow us to handle extensible functions with very little hard coding, it is OK if we
* impose extra/different limits on how an integer may be legally be formated in this case. This will also
* only show up in code that describes the interface to the standard function of IEC 61131-3, which the user
* will not ever get to see. We write that IEC 61131-3 code ourselves!
*
* Example of source code we will be parsing and analysing:
*
* FUNCTION ADD : REAL VAR_INPUT IN 1 .. : REAL; END_VAR RETURN; END_FUNCTION
* ^^^
*
* FUNCTION MUX : REAL VAR_INPUT K : USINT; IN 0 .. : REAL; END_VAR RETURN; END_FUNCTION
* ^^^
*
* Basically, currently this will only be either a '0' or a '1' !!
*/
/* NOTE: it must ignore underscores! */
static int extract_first_index_value(symbol_c *sym) {
std::string str = "";
integer_c *integer;
long int ret;
if ((integer = dynamic_cast<integer_c *>(sym)) == NULL) ERROR;
for(unsigned int i = 0; i < strlen(integer->value); i++)
if (integer->value[i] != '_') str += integer->value[i];
errno = 0; // since strtoXX() may legally return 0, we must set errno to 0 to detect errors correctly!
ret = strtol(str.c_str(), NULL, 10);
if (errno != 0) ERROR;
if (ret < 0) ERROR; // the following code assumes that the first index will never be negative!
if (ret > std::numeric_limits< int >::max()) ERROR; // output of this function is only an int!!
return ret;
}
/* compare the name of two __extensible__ function parameters.
* The usual use case is to have one of the parameters as used
* in the function declaration, and another as used in a formal function call.
*
* Will return:
* < 0 : if two parameters are not compatible, or one is invalid
* >= 0 : if both parameters ..........
*/
/*
* ("in", "i0") -> returns error (<0)
* ("in1", "in") -> returns error (<0)
* ("in", "in") -> returns error (<0)
* ("in", "inw") -> returns error (<0)
* ("in", "in10.4") -> returns error (<0)
* ("in", "in10e") -> returns error (<0)
* ("in", "") -> returns error (<0)
* ("", "in10e") -> returns error (<0)
* ("in", "in0") -> returns 0
* ("in", "in9") -> returns 9
* ("in", "in42") -> returns 42
* ("in", "in-42") -> returns -42 (error!)
*/
int function_param_iterator_c::cmp_extparam_names(const char* s1, const char* s2) {
int res;
char *endptr;
int len;
if ((s1 == NULL) || (s2 == NULL) || (*s1 == '\0') || (*s2 == '\0')) return -1;
len = strlen(s1);
if (strncasecmp(s1, s2, len)) return -2;
s1 = &s2[len];
if (*s1 == '\0') return -3;
res = strtol(s1, &endptr, 10);
if (*endptr != '\0') return -4;
return res;
}
void* function_param_iterator_c::handle_param_list(list_c *list) {
switch (current_operation) {
case iterate_op:
if (next_param <= param_count + list->n)
return list->get_element(next_param - param_count - 1);
/* the desired param is not on this list... */
param_count += list->n;
break;
case search_op:
for(int i = 0; i < list->n; i++) {
symbol_c *sym = list->get_element(i);
extensible_input_parameter_c *extensible_parameter = dynamic_cast<extensible_input_parameter_c *>(sym);
if (extensible_parameter != NULL) {
sym = extensible_parameter->var_name;
current_param_is_extensible = true;
_first_extensible_param_index = extract_first_index_value(extensible_parameter->first_index);
}
identifier_c *variable_name = dynamic_cast<identifier_c *>(sym);
if (variable_name == NULL) ERROR;
if (!current_param_is_extensible)
if (strcasecmp(search_param_name->value, variable_name->value) == 0)
/* FOUND! This is the same parameter!! */
return (void *)variable_name;
if (current_param_is_extensible) {
current_extensible_param_index = cmp_extparam_names(variable_name->value, search_param_name->value);
if (current_extensible_param_index >= 0)
/* FOUND! This is a compatible extensible parameter!! */
return (void *)variable_name;
}
}
break;
} /* switch */
/* Not found! */
return NULL;
}
void* function_param_iterator_c::handle_single_param(symbol_c *var_name) {
switch (current_operation) {
case iterate_op:
param_count++;
if (next_param == param_count)
return var_name;
break;
case search_op:
extensible_input_parameter_c *extensible_parameter = dynamic_cast<extensible_input_parameter_c *>(var_name);
if (extensible_parameter != NULL) {
var_name = extensible_parameter->var_name;
current_param_is_extensible = true;
_first_extensible_param_index = extract_first_index_value(extensible_parameter->first_index);
}
identifier_c *variable_name = dynamic_cast<identifier_c *>(var_name);
if (variable_name == NULL) ERROR;
if (!current_param_is_extensible)
if (strcasecmp(search_param_name->value, variable_name->value) == 0)
/* FOUND! This is the same parameter!! */
return (void *)variable_name;
if (current_param_is_extensible) {
current_extensible_param_index = cmp_extparam_names(variable_name->value, search_param_name->value);
if (current_extensible_param_index >= 0)
/* FOUND! This is a compatible extensible parameter!! */
return (void *)variable_name;
}
break;
} /* switch */
/* Not found! */
return NULL;
}
void* function_param_iterator_c::iterate_list(list_c *list) {
void *res;
for (int i = 0; i < list->n; i++) {
res = list->get_element(i)->accept(*this);
if (res != NULL)
return res;
}
return NULL;
}
/* start off at the first parameter once again... */
void function_param_iterator_c::reset(void) {
next_param = param_count = 0;
_first_extensible_param_index = -1;
current_param_is_extensible = false;
current_param_name = NULL;
current_param_type = NULL;
current_param_default_value = NULL;
last_returned_parameter = NULL; /* the last parameter returned by search() or next() */
}
/* initialise the iterator object.
* We must be given a reference to one of the following
* - function_declaration_c
* - function_block_declaration_c
* - program_declaration_c
* that will be analysed...
*/
function_param_iterator_c::function_param_iterator_c(symbol_c *pou_decl) {
/* do some consistency checks... */
function_declaration_c * f_decl = dynamic_cast<function_declaration_c *>(pou_decl);
function_block_declaration_c *fb_decl = dynamic_cast<function_block_declaration_c *>(pou_decl);
program_declaration_c * p_decl = dynamic_cast<program_declaration_c *>(pou_decl);
if ((NULL == f_decl) && (NULL == fb_decl) && (NULL == p_decl))
ERROR;
/* OK. Now initialise this object... */
this->f_decl = pou_decl;
reset();
}
/* Skip to the next parameter. After object creation,
* the object references on parameter _before_ the first, so
* this function must be called once to get the object to
* reference the first parameter...
*
* Returns the parameter's name!
*/
identifier_c *function_param_iterator_c::next(void) {
void *res;
identifier_c *identifier;
if (current_param_is_extensible) {
current_extensible_param_index++;
return current_param_name;
}
last_returned_parameter = NULL;
param_count = 0;
en_eno_param_implicit = false;
next_param++;
current_operation = function_param_iterator_c::iterate_op;
res = f_decl->accept(*this);
if (res == NULL)
return NULL;
symbol_c *sym = (symbol_c *)res;
extensible_input_parameter_c *extensible_parameter = dynamic_cast<extensible_input_parameter_c *>(sym);
if (extensible_parameter != NULL) {
sym = extensible_parameter->var_name;
current_param_is_extensible = true;
_first_extensible_param_index = extract_first_index_value(extensible_parameter->first_index);
current_extensible_param_index = _first_extensible_param_index;
}
identifier = dynamic_cast<identifier_c *>(sym);
if (identifier == NULL)
ERROR;
current_param_name = identifier;
last_returned_parameter = current_param_name;
return current_param_name;
}
/* Search for the value passed to the parameter named <param_name>... */
identifier_c *function_param_iterator_c::search(symbol_c *param_name) {
if (NULL == param_name) ERROR;
search_param_name = dynamic_cast<identifier_c *>(param_name);
if (NULL == search_param_name) ERROR;
en_eno_param_implicit = false;
current_param_is_extensible = false;
current_operation = function_param_iterator_c::search_op;
void *res = f_decl->accept(*this);
identifier_c *res_param_name = dynamic_cast<identifier_c *>((symbol_c *)res);
last_returned_parameter = res_param_name;
return res_param_name;
}
identifier_c *function_param_iterator_c::search(const char *param_name) {
identifier_c param_name_id(param_name);
return search(¶m_name_id);
}
/* Returns the currently referenced parameter's default value,
* or NULL if none is specified in the function declrataion itself.
*/
symbol_c *function_param_iterator_c::default_value(void) {
if (NULL == last_returned_parameter)
return NULL;
return current_param_default_value;
}
/* Returns the currently referenced parameter's type name. */
symbol_c *function_param_iterator_c::param_type(void) {
if (NULL == last_returned_parameter)
return NULL;
return current_param_type;
}
/* Returns if currently referenced parameter is an implicit defined EN/ENO parameter. */
bool function_param_iterator_c::is_en_eno_param_implicit(void) {
if (NULL == last_returned_parameter)
ERROR;
return en_eno_param_implicit;
}
/* Returns if currently referenced parameter is an extensible parameter. */
/* extensible paramters only occur in some standard functions, e.g. AND(word#34, word#44, word#65); */
bool function_param_iterator_c::is_extensible_param(void) {
if (NULL == last_returned_parameter)
ERROR;
return current_param_is_extensible;
}
/* Returns the index of the current extensible parameter. */
/* If the current parameter is not an extensible paramter, returns -1 */
int function_param_iterator_c::extensible_param_index(void) {
if (NULL == last_returned_parameter)
ERROR;
return (current_param_is_extensible? current_extensible_param_index : -1);
}
/* Returns the index of the first extensible parameter, or -1 if no extensible parameter found. */
/* WARNING: Will only return the correct value _after_ an extensible parameter has been found! */
int function_param_iterator_c::first_extensible_param_index(void) {
return _first_extensible_param_index;
}
/* Returns the currently referenced parameter's data passing direction.
* i.e. VAR_INPUT, VAR_OUTPUT or VAR_INOUT
*/
function_param_iterator_c::param_direction_t function_param_iterator_c::param_direction(void) {
if (NULL == last_returned_parameter)
ERROR;
return current_param_direction;
}
void *function_param_iterator_c::visit(implicit_definition_c *symbol) {
en_eno_param_implicit = true;
return NULL;
}
/****************************************/
/* 1.4.3 - Declaration & Initialisation */
/****************************************/
void *function_param_iterator_c::visit(input_declarations_c *symbol) {
TRACE("input_declarations_c");
current_param_direction = direction_in;
return symbol->input_declaration_list->accept(*this);
}
void *function_param_iterator_c::visit(input_declaration_list_c *symbol) {TRACE("input_declaration_list_c"); return iterate_list(symbol);}
void *function_param_iterator_c::visit(edge_declaration_c *symbol) {TRACE("edge_declaration_c"); return symbol->var1_list->accept(*this);}
void *function_param_iterator_c::visit(en_param_declaration_c *symbol) {
TRACE("en_param_declaration_c");
/* It is OK to store these values in the current_param_XXX
* variables, because if the desired parameter is not in the
* variable list we will be analysing, the current_param_XXXX
* variables will get overwritten when we visit the next
* var1_init_decl_c list!
*/
current_param_default_value = spec_init_sperator_c::get_init(symbol->type_decl);
current_param_type = spec_init_sperator_c::get_spec(symbol->type_decl);
void *res = handle_single_param(symbol->name);
/* If we have found the parameter we will be returning, we set the en_eno_param_implicit to TRUE if implicitly defined */
if (res != NULL) symbol->method->accept(*this);
return res;
}
/* var1_list ':' array_spec_init */
//SYM_REF2(array_var_init_decl_c, var1_list, array_spec_init)
void *function_param_iterator_c::visit(array_var_init_decl_c *symbol) {
TRACE("array_var_init_decl_c");
current_param_default_value = spec_init_sperator_c::get_init(symbol->array_spec_init);
current_param_type = spec_init_sperator_c::get_spec(symbol->array_spec_init);
return symbol->var1_list->accept(*this);
}
/* var1_list ':' initialized_structure */
//SYM_REF2(structured_var_init_decl_c, var1_list, initialized_structure)
void *function_param_iterator_c::visit(structured_var_init_decl_c *symbol) {
TRACE("structured_var_init_decl_c");
current_param_default_value = spec_init_sperator_c::get_init(symbol->initialized_structure);
current_param_type = spec_init_sperator_c::get_spec(symbol->initialized_structure);
return symbol->var1_list->accept(*this);
}
/* fb_name_list ':' function_block_type_name ASSIGN structure_initialization */
/* structure_initialization -> may be NULL ! */
// SYM_REF3(fb_name_decl_c, fb_name_list, function_block_type_name, structure_initialization)
void *function_param_iterator_c::visit(fb_name_decl_c *symbol) {
TRACE("structured_var_init_decl_c");
current_param_default_value = spec_init_sperator_c::get_init(symbol->fb_spec_init);
current_param_type = spec_init_sperator_c::get_spec(symbol->fb_spec_init);
return symbol->fb_name_list->accept(*this);
}
/* fb_name_list ',' fb_name */
// SYM_LIST(fb_name_list_c)
void *function_param_iterator_c::visit(fb_name_list_c *symbol) {TRACE("fb_name_list_c"); return handle_param_list(symbol);}
void *function_param_iterator_c::visit(output_declarations_c *symbol) {
TRACE("output_declarations_c");
current_param_direction = direction_out;
return symbol->var_init_decl_list->accept(*this);
}
void *function_param_iterator_c::visit(eno_param_declaration_c *symbol) {
TRACE("eno_param_declaration_c");
/* It is OK to store these values in the current_param_XXX
* variables, because if the desired parameter is not in the
* variable list we will be analysing, the current_param_XXXX
* variables will get overwritten when we visit the next
* var1_init_decl_c list!
*/
current_param_default_value = NULL;
current_param_type = symbol->type;
void *res = handle_single_param(symbol->name);
/* If we have found the parameter we will be returning, we set the en_eno_param_implicit to TRUE if implicitly defined */
if (res != NULL) symbol->method->accept(*this);
return res;
}
void *function_param_iterator_c::visit(input_output_declarations_c *symbol) {
TRACE("input_output_declarations_c");
current_param_direction = direction_inout;
return symbol->var_declaration_list->accept(*this);
}
void *function_param_iterator_c::visit(var_declaration_list_c *symbol) {TRACE("var_declaration_list_c"); return iterate_list(symbol);}
/* var1_list ':' array_specification */
//SYM_REF2(array_var_declaration_c, var1_list, array_specification)
void *function_param_iterator_c::visit(array_var_declaration_c *symbol) {
TRACE("array_var_declaration_c");
current_param_default_value = NULL;
current_param_type = symbol->array_specification;
return symbol->var1_list->accept(*this);
}
/* var1_list ':' structure_type_name */
//SYM_REF2(structured_var_declaration_c, var1_list, structure_type_name)
void *function_param_iterator_c::visit(structured_var_declaration_c *symbol) {
TRACE("structured_var_declaration_c");
current_param_default_value = NULL;
current_param_type = symbol->structure_type_name;
return symbol->var1_list->accept(*this);
}
/* VAR [CONSTANT] var_init_decl_list END_VAR */
void *function_param_iterator_c::visit(var_declarations_c *symbol) {TRACE("var_declarations_c"); return NULL;}
/*| VAR_EXTERNAL [CONSTANT] external_declaration_list END_VAR */
/* option -> may be NULL ! */
// SYM_REF2(external_var_declarations_c, option, external_declaration_list)
void *function_param_iterator_c::visit(external_var_declarations_c *symbol) {
TRACE("external_var_declarations_c");
current_param_direction = direction_extref;
return symbol->external_declaration_list->accept(*this);
}
/* helper symbol for external_var_declarations */
/*| external_declaration_list external_declaration';' */
// SYM_LIST(external_declaration_list_c)
void *function_param_iterator_c::visit(external_declaration_list_c *symbol) {TRACE("external_declaration_list_c"); return iterate_list(symbol);}
/* global_var_name ':' (simple_specification|subrange_specification|enumerated_specification|array_specification|prev_declared_structure_type_name|function_block_type_name */
//SYM_REF2(external_declaration_c, global_var_name, specification)
void *function_param_iterator_c::visit(external_declaration_c *symbol) {
TRACE("external_declaration_c");
/* It is OK to store these values in the current_param_XXX
* variables, because if the desired parameter is not in the
* variable list we will be analysing, the current_param_XXXX
* variables will get overwritten when we visit the next
* var1_init_decl_c list!
*/
current_param_default_value = spec_init_sperator_c::get_init(symbol->specification);
current_param_type = spec_init_sperator_c::get_spec(symbol->specification);
return handle_single_param(symbol->global_var_name);
}
#if 0
/*| VAR_GLOBAL [CONSTANT|RETAIN] global_var_decl_list END_VAR */
/* option -> may be NULL ! */
SYM_REF2(global_var_declarations_c, option, global_var_decl_list)
/* helper symbol for global_var_declarations */
/*| global_var_decl_list global_var_decl ';' */
SYM_LIST(global_var_decl_list_c)
/*| global_var_spec ':' [located_var_spec_init|function_block_type_name] */
/* type_specification ->may be NULL ! */
SYM_REF2(global_var_decl_c, global_var_spec, type_specification)
/*| global_var_name location */
SYM_REF2(global_var_spec_c, global_var_name, location)
/* AT direct_variable */
SYM_REF2(location_c, direct_variable, unused)
/*| global_var_list ',' global_var_name */
SYM_LIST(global_var_list_c)
/* var1_list ':' single_byte_string_spec */
SYM_REF2(single_byte_string_var_declaration_c, var1_list, single_byte_string_spec)
/* STRING ['[' integer ']'] [ASSIGN single_byte_character_string] */
/* integer ->may be NULL ! */
/* single_byte_character_string ->may be NULL ! */
SYM_REF2(single_byte_string_spec_c, integer, single_byte_character_string)
/* var1_list ':' double_byte_string_spec */
SYM_REF2(double_byte_string_var_declaration_c, var1_list, double_byte_string_spec)
/* WSTRING ['[' integer ']'] [ASSIGN double_byte_character_string] */
/* integer ->may be NULL ! */
/* double_byte_character_string ->may be NULL ! */
SYM_REF2(double_byte_string_spec_c, integer, double_byte_character_string)
/*| VAR [RETAIN|NON_RETAIN] incompl_located_var_decl_list END_VAR */
/* option ->may be NULL ! */
SYM_REF2(incompl_located_var_declarations_c, option, incompl_located_var_decl_list)
/* helper symbol for incompl_located_var_declarations */
/*| incompl_located_var_decl_list incompl_located_var_decl ';' */
SYM_LIST(incompl_located_var_decl_list_c)
/* variable_name incompl_location ':' var_spec */
SYM_REF4(incompl_located_var_decl_c, variable_name, incompl_location, var_spec, unused)
/* AT incompl_location_token */
SYM_TOKEN(incompl_location_c)
#endif
void *function_param_iterator_c::visit(var1_init_decl_c *symbol) {
TRACE("var1_init_decl_c");
/* It is OK to store these values in the current_param_XXX
* variables, because if the desired parameter is not in the
* variable list we will be analysing, the current_param_XXXX
* variables will get overwritten when we visit the next
* var1_init_decl_c list!
*/
current_param_default_value = spec_init_sperator_c::get_init(symbol->spec_init);
current_param_type = spec_init_sperator_c::get_spec(symbol->spec_init);
return symbol->var1_list->accept(*this);
}
void *function_param_iterator_c::visit(var1_list_c *symbol) {
TRACE("var1_list_c");
return handle_param_list(symbol);
}
void *function_param_iterator_c::visit(var_init_decl_list_c *symbol) {TRACE("var_init_decl_list_c"); return iterate_list(symbol);}
/***********************/
/* B 1.5.1 - Functions */
/***********************/
void *function_param_iterator_c::visit(function_declaration_c *symbol) {TRACE("function_declaration_c"); return symbol->var_declarations_list->accept(*this);}
/* intermediate helper symbol for function_declaration */
void *function_param_iterator_c::visit(var_declarations_list_c *symbol) {TRACE("var_declarations_list_c"); return iterate_list(symbol);}
void *function_param_iterator_c::visit(function_var_decls_c *symbol) {TRACE("function_var_decls_c"); /* ignore */ return NULL;}
/*****************************/
/* B 1.5.2 - Function Blocks */
/*****************************/
/* FUNCTION_BLOCK derived_function_block_name io_OR_other_var_declarations function_block_body END_FUNCTION_BLOCK */
void *function_param_iterator_c::visit(function_block_declaration_c *symbol) {TRACE("function_block_declaration_c"); return symbol->var_declarations->accept(*this);}
/* intermediate helper symbol for function_declaration */
/* { io_var_declarations | other_var_declarations } */
/*
* NOTE: we re-use the var_declarations_list_c
*/
/* VAR_TEMP temp_var_decl_list END_VAR */
void *function_param_iterator_c::visit(temp_var_decls_c *symbol) {TRACE("temp_var_decls_c"); /* ignore */ return NULL;}
void *function_param_iterator_c::visit(temp_var_decls_list_c *symbol) {TRACE("temp_var_decls_list_c"); /* ignore */ return NULL;}
/* VAR NON_RETAIN var_init_decl_list END_VAR */
void *function_param_iterator_c::visit(non_retentive_var_decls_c *symbol) {TRACE("non_retentive_var_decls_c"); /* ignore */ return NULL;}
/**********************/
/* B 1.5.3 - Programs */
/**********************/
/* PROGRAM program_type_name program_var_declarations_list function_block_body END_PROGRAM */
// SYM_REF4(program_declaration_c, program_type_name, var_declarations, function_block_body, unused)
void *function_param_iterator_c::visit(program_declaration_c *symbol) {TRACE("program_declaration_c"); return symbol->var_declarations->accept(*this);}
/* intermediate helper symbol for program_declaration_c */
/* { io_var_declarations | other_var_declarations } */
/*
* NOTE: we re-use the var_declarations_list_c
*/