NetBSD/tests/usr.bin/xlint/lint1/gcc_attribute.c

135 lines
3.9 KiB
C

/* $NetBSD: gcc_attribute.c,v 1.13 2023/03/28 14:44:34 rillig Exp $ */
# 3 "gcc_attribute.c"
/*
* Tests for the various attributes for functions, types, statements that are
* provided by GCC.
*
* https://gcc.gnu.org/onlinedocs/gcc/Attribute-Syntax.html
*/
/* lint1-extra-flags: -X 351 */
void __attribute__((noinline))
do_not_inline(void)
{
}
/* All pointer arguments must be nonnull. */
void __attribute__((nonnull))
function_nonnull(void *, const void *, int);
/*
* The documentation suggests that the argument list of nonnull be nonempty,
* but GCC 9.3.0 accepts an empty list as well, treating all parameters as
* nonnull.
*/
void __attribute__((nonnull()))
function_nonnull_list(void *, const void *, int);
/* Arguments 1 and 2 must be nonnull. */
void __attribute__((nonnull(1, 2)))
function_nonnull_list(void *, const void *, int);
/*
* Unknown attributes are skipped, as lint does not have a list of all known
* GCC attributes.
*/
void __attribute__((unknown_attribute))
function_with_unknown_attribute(void);
/*
* There is an attribute called 'pcs', but that attribute must not prevent an
* ordinary variable from being named the same. Starting with scan.l 1.77
* from 2017-01-07, that variable name generated a syntax error. Fixed in
* lex.c 1.33 from 2021-05-03.
*
* Seen in yds.c, function yds_allocate_slots.
*/
int
local_variable_pcs(void)
{
int pcs = 3;
return pcs;
}
/*
* FIXME: The attributes are handled by different grammar rules even though
* they occur in the same syntactical position.
*
* Grammar rule abstract_decl_param_list handles the first attribute.
*
* Grammar rule direct_abstract_declarator handles all remaining attributes.
*
* Since abstract_decl_param_list contains type_attribute_opt, this could be
* the source of the many shift/reduce conflicts in the grammar.
*/
int
func(
int(int)
__attribute__((__noreturn__))
__attribute__((__noreturn__))
);
/*
* https://gcc.gnu.org/onlinedocs/gcc/Attribute-Syntax.html says that the
* attribute-list is a "possibly empty comma-separated sequence of
* attributes".
*
* No matter whether this particular example is interpreted as an empty list
* or a list containing a single empty attribute, the result is the same in
* both cases.
*/
void one_empty_attribute(void)
__attribute__((/* none */));
/*
* https://gcc.gnu.org/onlinedocs/gcc/Attribute-Syntax.html further says that
* each individual attribute may be "Empty. Empty attributes are ignored".
*/
void two_empty_attributes(void)
__attribute__((/* none */, /* still none */));
/*
* Ensure that __attribute__ can be specified everywhere in a declaration.
* This is the simplest possible requirement that covers all valid code.
* It accepts invalid code as well, but these cases are covered by GCC and
* Clang already.
*
* Since lint only parses the attributes but doesn't really relate them to
* identifiers or other entities, ensuring that valid code can be parsed is
* enough for now.
*
* To really associate __attribute__ with the corresponding entity, the
* grammar needs to be rewritten, see the example with __noreturn__ above.
*/
__attribute__((deprecated("d1")))
const
__attribute__((deprecated("d2")))
int
__attribute__((deprecated("d3")))
*
// The below line would produce a syntax error.
// __attribute__((deprecated("d3")))
const
__attribute__((deprecated("d4")))
identifier
__attribute__((deprecated("d5")))
(
__attribute__((deprecated("d6")))
void
__attribute__((deprecated("d7")))
)
__attribute__((deprecated("d8")))
;
/*
* The attribute 'const' provides stronger guarantees than 'pure', and
* 'volatile' is not defined. To keep the grammar simple, any T_QUAL is
* allowed at this point, but only syntactically.
*/
int const_function(int) __attribute__((const));
/* cover 'gcc_attribute_spec: T_QUAL' */
/* expect+1: error: syntax error 'volatile' [249] */
int volatile_function(int) __attribute__((volatile));