}
}
-/* Called when the index of a switch statement is an enumerated type
- and there is no default label.
+/* Given a switch statement with an expression that is an enumeration
+ type, warn if any of the enumeration type's literals are not
+ covered by the case expressions of the switch. Also, warn if there
+ are any extra switch cases that are *not* elements of the
+ enumerated type.
- Checks that all enumeration literals are covered by the case
- expressions of a switch. Also, warn if there are any extra
- switch cases that are *not* elements of the enumerated type.
+ Historical note:
- If all enumeration literals were covered by the case expressions,
- turn one of the expressions into the default expression since it should
- not be possible to fall through such a switch. */
+ At one stage this function would: ``If all enumeration literals
+ were covered by the case expressions, turn one of the expressions
+ into the default expression since it should not be possible to fall
+ through such a switch.''
+
+ That code has since been removed as: ``This optimization is
+ disabled because it causes valid programs to fail. ANSI C does not
+ guarantee that an expression with enum type will have a value that
+ is the same as one of the enumeration literals.'' */
void
check_for_full_enumeration_handling (type)
/* The allocated size of cases_seen, in chars. */
HOST_WIDE_INT bytes_needed;
- if (! warn_switch)
- return;
-
size = all_cases_count (type, &sparseness);
bytes_needed = (size + HOST_BITS_PER_CHAR) / HOST_BITS_PER_CHAR;
&& case_stack->data.case_stmt.case_list->left)
case_stack->data.case_stmt.case_list
= case_tree2list (case_stack->data.case_stmt.case_list, 0);
- if (warn_switch)
- for (n = case_stack->data.case_stmt.case_list; n; n = n->right)
- {
- for (chain = TYPE_VALUES (type);
- chain && !tree_int_cst_equal (n->low, TREE_VALUE (chain));
- chain = TREE_CHAIN (chain))
- ;
-
- if (!chain)
- {
- if (TYPE_NAME (type) == 0)
- warning ("case value `%ld' not in enumerated type",
- (long) TREE_INT_CST_LOW (n->low));
- else
- warning ("case value `%ld' not in enumerated type `%s'",
- (long) TREE_INT_CST_LOW (n->low),
- IDENTIFIER_POINTER ((TREE_CODE (TYPE_NAME (type))
- == IDENTIFIER_NODE)
- ? TYPE_NAME (type)
- : DECL_NAME (TYPE_NAME (type))));
- }
- if (!tree_int_cst_equal (n->low, n->high))
- {
- for (chain = TYPE_VALUES (type);
- chain && !tree_int_cst_equal (n->high, TREE_VALUE (chain));
- chain = TREE_CHAIN (chain))
- ;
-
- if (!chain)
- {
- if (TYPE_NAME (type) == 0)
- warning ("case value `%ld' not in enumerated type",
- (long) TREE_INT_CST_LOW (n->high));
- else
- warning ("case value `%ld' not in enumerated type `%s'",
- (long) TREE_INT_CST_LOW (n->high),
- IDENTIFIER_POINTER ((TREE_CODE (TYPE_NAME (type))
- == IDENTIFIER_NODE)
- ? TYPE_NAME (type)
- : DECL_NAME (TYPE_NAME (type))));
- }
- }
- }
+ for (n = case_stack->data.case_stmt.case_list; n; n = n->right)
+ {
+ for (chain = TYPE_VALUES (type);
+ chain && !tree_int_cst_equal (n->low, TREE_VALUE (chain));
+ chain = TREE_CHAIN (chain))
+ ;
+
+ if (!chain)
+ {
+ if (TYPE_NAME (type) == 0)
+ warning ("case value `%ld' not in enumerated type",
+ (long) TREE_INT_CST_LOW (n->low));
+ else
+ warning ("case value `%ld' not in enumerated type `%s'",
+ (long) TREE_INT_CST_LOW (n->low),
+ IDENTIFIER_POINTER ((TREE_CODE (TYPE_NAME (type))
+ == IDENTIFIER_NODE)
+ ? TYPE_NAME (type)
+ : DECL_NAME (TYPE_NAME (type))));
+ }
+ if (!tree_int_cst_equal (n->low, n->high))
+ {
+ for (chain = TYPE_VALUES (type);
+ chain && !tree_int_cst_equal (n->high, TREE_VALUE (chain));
+ chain = TREE_CHAIN (chain))
+ ;
+
+ if (!chain)
+ {
+ if (TYPE_NAME (type) == 0)
+ warning ("case value `%ld' not in enumerated type",
+ (long) TREE_INT_CST_LOW (n->high));
+ else
+ warning ("case value `%ld' not in enumerated type `%s'",
+ (long) TREE_INT_CST_LOW (n->high),
+ IDENTIFIER_POINTER ((TREE_CODE (TYPE_NAME (type))
+ == IDENTIFIER_NODE)
+ ? TYPE_NAME (type)
+ : DECL_NAME (TYPE_NAME (type))));
+ }
+ }
+ }
}
/* Free CN, and its children. */
/* An ERROR_MARK occurs for various reasons including invalid data type. */
if (index_type != error_mark_node)
{
- /* If switch expression was an enumerated type, check that all
- enumeration literals are covered by the cases.
- No sense trying this if there's a default case, however. */
+ /* If the switch expression was an enumerated type, check that
+ exactly all enumeration literals are covered by the cases.
+ The check is made -Wswitch was specified and there is no
+ default case. */
- if (!thiscase->data.case_stmt.default_label
+ if ((warn_switch && !thiscase->data.case_stmt.default_label)
&& TREE_CODE (orig_type) == ENUMERAL_TYPE
&& TREE_CODE (index_expr) != INTEGER_CST)
check_for_full_enumeration_handling (orig_type);
+ if (warn_switch_default && !thiscase->data.case_stmt.default_label)
+ warning ("switch missing default case");
+
/* If we don't have a default-label, create one here,
after the body of the switch. */
if (thiscase->data.case_stmt.default_label == 0)
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