removed set_opt_overflow_unsafe_transform(), not needed anymore
[cparser] / parser.c
index 306de11..3323840 100644 (file)
--- a/parser.c
+++ b/parser.c
@@ -1,13 +1,33 @@
+/*
+ * This file is part of cparser.
+ * Copyright (C) 2007-2008 Matthias Braun <matze@braunis.de>
+ *
+ * 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 2
+ * 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, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
 #include <config.h>
 
 #include <assert.h>
 #include <stdarg.h>
 #include <stdbool.h>
 
+#include "parser.h"
 #include "diagnostic.h"
 #include "format_check.h"
-#include "parser.h"
 #include "lexer.h"
+#include "symbol_t.h"
 #include "token_t.h"
 #include "types.h"
 #include "type_t.h"
@@ -195,31 +215,32 @@ static statement_t *allocate_statement_zero(statement_kind_t kind)
 static size_t get_expression_struct_size(expression_kind_t kind)
 {
        static const size_t sizes[] = {
-               [EXPR_INVALID]             = sizeof(expression_base_t),
-               [EXPR_REFERENCE]           = sizeof(reference_expression_t),
-               [EXPR_CONST]               = sizeof(const_expression_t),
-               [EXPR_CHAR_CONST]          = sizeof(const_expression_t),
-               [EXPR_STRING_LITERAL]      = sizeof(string_literal_expression_t),
-               [EXPR_WIDE_STRING_LITERAL] = sizeof(wide_string_literal_expression_t),
-               [EXPR_COMPOUND_LITERAL]    = sizeof(compound_literal_expression_t),
-               [EXPR_CALL]                = sizeof(call_expression_t),
-               [EXPR_UNARY_FIRST]         = sizeof(unary_expression_t),
-               [EXPR_BINARY_FIRST]        = sizeof(binary_expression_t),
-               [EXPR_CONDITIONAL]         = sizeof(conditional_expression_t),
-               [EXPR_SELECT]              = sizeof(select_expression_t),
-               [EXPR_ARRAY_ACCESS]        = sizeof(array_access_expression_t),
-               [EXPR_SIZEOF]              = sizeof(typeprop_expression_t),
-               [EXPR_ALIGNOF]             = sizeof(typeprop_expression_t),
-               [EXPR_CLASSIFY_TYPE]       = sizeof(classify_type_expression_t),
-               [EXPR_FUNCTION]            = sizeof(string_literal_expression_t),
-               [EXPR_PRETTY_FUNCTION]     = sizeof(string_literal_expression_t),
-               [EXPR_BUILTIN_SYMBOL]      = sizeof(builtin_symbol_expression_t),
-               [EXPR_BUILTIN_CONSTANT_P]  = sizeof(builtin_constant_expression_t),
-               [EXPR_BUILTIN_PREFETCH]    = sizeof(builtin_prefetch_expression_t),
-               [EXPR_OFFSETOF]            = sizeof(offsetof_expression_t),
-               [EXPR_VA_START]            = sizeof(va_start_expression_t),
-               [EXPR_VA_ARG]              = sizeof(va_arg_expression_t),
-               [EXPR_STATEMENT]           = sizeof(statement_expression_t),
+               [EXPR_INVALID]                 = sizeof(expression_base_t),
+               [EXPR_REFERENCE]               = sizeof(reference_expression_t),
+               [EXPR_CONST]                   = sizeof(const_expression_t),
+               [EXPR_CHARACTER_CONSTANT]      = sizeof(const_expression_t),
+               [EXPR_WIDE_CHARACTER_CONSTANT] = sizeof(const_expression_t),
+               [EXPR_STRING_LITERAL]          = sizeof(string_literal_expression_t),
+               [EXPR_WIDE_STRING_LITERAL]   = sizeof(wide_string_literal_expression_t),
+               [EXPR_COMPOUND_LITERAL]        = sizeof(compound_literal_expression_t),
+               [EXPR_CALL]                    = sizeof(call_expression_t),
+               [EXPR_UNARY_FIRST]             = sizeof(unary_expression_t),
+               [EXPR_BINARY_FIRST]            = sizeof(binary_expression_t),
+               [EXPR_CONDITIONAL]             = sizeof(conditional_expression_t),
+               [EXPR_SELECT]                  = sizeof(select_expression_t),
+               [EXPR_ARRAY_ACCESS]            = sizeof(array_access_expression_t),
+               [EXPR_SIZEOF]                  = sizeof(typeprop_expression_t),
+               [EXPR_ALIGNOF]                 = sizeof(typeprop_expression_t),
+               [EXPR_CLASSIFY_TYPE]           = sizeof(classify_type_expression_t),
+               [EXPR_FUNCTION]                = sizeof(string_literal_expression_t),
+               [EXPR_PRETTY_FUNCTION]         = sizeof(string_literal_expression_t),
+               [EXPR_BUILTIN_SYMBOL]          = sizeof(builtin_symbol_expression_t),
+               [EXPR_BUILTIN_CONSTANT_P]      = sizeof(builtin_constant_expression_t),
+               [EXPR_BUILTIN_PREFETCH]        = sizeof(builtin_prefetch_expression_t),
+               [EXPR_OFFSETOF]                = sizeof(offsetof_expression_t),
+               [EXPR_VA_START]                = sizeof(va_start_expression_t),
+               [EXPR_VA_ARG]                  = sizeof(va_arg_expression_t),
+               [EXPR_STATEMENT]               = sizeof(statement_expression_t),
        };
        if(kind >= EXPR_UNARY_FIRST && kind <= EXPR_UNARY_LAST) {
                return sizes[EXPR_UNARY_FIRST];
@@ -457,6 +478,10 @@ static void eat_paren(void)
                if(token.type == ')' || token.type == ';' || token.type == '}') {
                        return;
                }
+               if(token.type == ')') {
+                       next_token();
+                       return;
+               }
                if(token.type == '(') {
                        eat_paren();
                        continue;
@@ -467,7 +492,6 @@ static void eat_paren(void)
                }
                next_token();
        }
-       eat(')');
 }
 
 #define expect(expected)                           \
@@ -514,7 +538,8 @@ static void set_scope(scope_t *new_scope)
  * Search a symbol in a given namespace and returns its declaration or
  * NULL if this symbol was not found.
  */
-static declaration_t *get_declaration(const symbol_t *const symbol, const namespace_t namespc)
+static declaration_t *get_declaration(const symbol_t *const symbol,
+                                      const namespace_t namespc)
 {
        declaration_t *declaration = symbol->declaration;
        for( ; declaration != NULL; declaration = declaration->symbol_next) {
@@ -2502,6 +2527,10 @@ static type_t *construct_declarator_type(construct_type_t *construct_list,
                        type_t         *array_type    = allocate_type_zero(TYPE_ARRAY, (source_position_t){NULL, 0});
 
                        expression_t *size_expression = parsed_array->size;
+                       if(size_expression != NULL) {
+                               size_expression
+                                       = create_implicit_cast(size_expression, type_size_t);
+                       }
 
                        array_type->base.qualifiers       = parsed_array->type_qualifiers;
                        array_type->array.element_type    = type;
@@ -2509,11 +2538,14 @@ static type_t *construct_declarator_type(construct_type_t *construct_list,
                        array_type->array.is_variable     = parsed_array->is_variable;
                        array_type->array.size_expression = size_expression;
 
-                       if(size_expression != NULL &&
-                                       is_constant_expression(size_expression)) {
-                               array_type->array.size_constant = true;
-                               array_type->array.size
-                                       = fold_constant(size_expression);
+                       if(size_expression != NULL) {
+                               if(is_constant_expression(size_expression)) {
+                                       array_type->array.size_constant = true;
+                                       array_type->array.size
+                                               = fold_constant(size_expression);
+                               } else {
+                                       array_type->array.is_vla = true;
+                               }
                        }
 
                        type_t *skipped_type = skip_typeref(type);
@@ -3464,6 +3496,9 @@ static expression_t *parse_string_const(void)
                }
                if (token.type != T_WIDE_STRING_LITERAL) {
                        expression_t *const cnst = allocate_expression_zero(EXPR_STRING_LITERAL);
+                       /* note: that we use type_char_ptr here, which is already the
+                        * automatic converted type. revert_automatic_type_conversion
+                        * will construct the array type */
                        cnst->base.type    = type_char_ptr;
                        cnst->string.value = res;
                        return cnst;
@@ -3514,15 +3549,39 @@ static expression_t *parse_int_const(void)
 /**
  * Parse a character constant.
  */
-static expression_t *parse_char_const(void)
+static expression_t *parse_character_constant(void)
 {
-       expression_t *cnst         = allocate_expression_zero(EXPR_CHAR_CONST);
+       expression_t *cnst = allocate_expression_zero(EXPR_CHARACTER_CONSTANT);
+
        cnst->base.source_position = HERE;
        cnst->base.type            = token.datatype;
-       cnst->conste.v.chars.begin = token.v.string.begin;
-       cnst->conste.v.chars.size  = token.v.string.size;
+       cnst->conste.v.character   = token.v.string;
 
-       if (cnst->conste.v.chars.size != 1) {
+       if (cnst->conste.v.character.size != 1) {
+               if (warning.multichar && (c_mode & _GNUC)) {
+                       /* TODO */
+                       warningf(HERE, "multi-character character constant");
+               } else {
+                       errorf(HERE, "more than 1 characters in character constant");
+               }
+       }
+       next_token();
+
+       return cnst;
+}
+
+/**
+ * Parse a wide character constant.
+ */
+static expression_t *parse_wide_character_constant(void)
+{
+       expression_t *cnst = allocate_expression_zero(EXPR_WIDE_CHARACTER_CONSTANT);
+
+       cnst->base.source_position    = HERE;
+       cnst->base.type               = token.datatype;
+       cnst->conste.v.wide_character = token.v.wide_string;
+
+       if (cnst->conste.v.wide_character.size != 1) {
                if (warning.multichar && (c_mode & _GNUC)) {
                        /* TODO */
                        warningf(HERE, "multi-character character constant");
@@ -3684,6 +3743,16 @@ type_t *revert_automatic_type_conversion(const expression_t *expression)
                        return type_left->pointer.points_to;
                }
 
+               case EXPR_STRING_LITERAL: {
+                       size_t size = expression->string.value.size;
+                       return make_array_type(type_char, size, TYPE_QUALIFIER_NONE);
+               }
+
+               case EXPR_WIDE_STRING_LITERAL: {
+                       size_t size = expression->wide_string.value.size;
+                       return make_array_type(type_wchar_t, size, TYPE_QUALIFIER_NONE);
+               }
+
                case EXPR_COMPOUND_LITERAL:
                        return expression->compound_literal.type;
 
@@ -4135,7 +4204,8 @@ static expression_t *parse_primary_expression(void)
 {
        switch (token.type) {
                case T_INTEGER:                  return parse_int_const();
-               case T_CHARS:                    return parse_char_const();
+               case T_CHARACTER_CONSTANT:       return parse_character_constant();
+               case T_WIDE_CHARACTER_CONSTANT:  return parse_wide_character_constant();
                case T_FLOATINGPOINT:            return parse_float_const();
                case T_STRING_LITERAL:
                case T_WIDE_STRING_LITERAL:      return parse_string_const();
@@ -5063,6 +5133,18 @@ static void semantic_binexpr_assign(binary_expression_t *expression)
        expression->base.type = orig_type_left;
 }
 
+/**
+ * Determine if the outermost operation (or parts thereof) of the given
+ * expression has no effect in order to generate a warning about this fact.
+ * Therefore in some cases this only examines some of the operands of the
+ * expression (see comments in the function and examples below).
+ * Examples:
+ *   f() + 23;    // warning, because + has no effect
+ *   x || f();    // no warning, because x controls execution of f()
+ *   x ? y : f(); // warning, because y has no effect
+ *   (void)x;     // no warning to be able to suppress the warning
+ * This function can NOT be used for an "expression has definitely no effect"-
+ * analysis. */
 static bool expression_has_effect(const expression_t *const expr)
 {
        switch (expr->kind) {
@@ -5070,9 +5152,11 @@ static bool expression_has_effect(const expression_t *const expr)
                case EXPR_INVALID:                   break;
                case EXPR_REFERENCE:                 return false;
                case EXPR_CONST:                     return false;
-               case EXPR_CHAR_CONST:                return false;
+               case EXPR_CHARACTER_CONSTANT:        return false;
+               case EXPR_WIDE_CHARACTER_CONSTANT:   return false;
                case EXPR_STRING_LITERAL:            return false;
                case EXPR_WIDE_STRING_LITERAL:       return false;
+
                case EXPR_CALL: {
                        const call_expression_t *const call = &expr->call;
                        if (call->function->kind != EXPR_BUILTIN_SYMBOL)
@@ -5083,12 +5167,16 @@ static bool expression_has_effect(const expression_t *const expr)
                                default:                 return false;
                        }
                }
+
+               /* Generate the warning if either the left or right hand side of a
+                * conditional expression has no effect */
                case EXPR_CONDITIONAL: {
                        const conditional_expression_t *const cond = &expr->conditional;
                        return
                                expression_has_effect(cond->true_expression) &&
                                expression_has_effect(cond->false_expression);
                }
+
                case EXPR_SELECT:                    return false;
                case EXPR_ARRAY_ACCESS:              return false;
                case EXPR_SIZEOF:                    return false;
@@ -5116,10 +5204,14 @@ static bool expression_has_effect(const expression_t *const expr)
                case EXPR_UNARY_POSTFIX_DECREMENT:   return true;
                case EXPR_UNARY_PREFIX_INCREMENT:    return true;
                case EXPR_UNARY_PREFIX_DECREMENT:    return true;
+
+               /* Treat void casts as if they have an effect in order to being able to
+                * suppress the warning */
                case EXPR_UNARY_CAST: {
-                       type_t *type = skip_typeref(expr->base.type);
+                       type_t *const type = skip_typeref(expr->base.type);
                        return is_type_atomic(type, ATOMIC_TYPE_VOID);
                }
+
                case EXPR_UNARY_CAST_IMPLICIT:       return true;
                case EXPR_UNARY_ASSUME:              return true;
                case EXPR_UNARY_BITFIELD_EXTRACT:    return false;
@@ -5151,8 +5243,14 @@ static bool expression_has_effect(const expression_t *const expr)
                case EXPR_BINARY_BITWISE_AND_ASSIGN: return true;
                case EXPR_BINARY_BITWISE_XOR_ASSIGN: return true;
                case EXPR_BINARY_BITWISE_OR_ASSIGN:  return true;
+
+               /* Only examine the right hand side of && and ||, because the left hand
+                * side already has the effect of controlling the execution of the right
+                * hand side */
                case EXPR_BINARY_LOGICAL_AND:
                case EXPR_BINARY_LOGICAL_OR:
+               /* Only examine the right hand side of a comma expression, because the left
+                * hand side has a separate warning */
                case EXPR_BINARY_COMMA:
                        return expression_has_effect(expr->binary.right);