gnulib: lib/verify.h annotate

annotate lib/verify.h @ 37191:2f1343191e67

verify: new macro 'assume' This is taken from Emacs, and should be generally useful. * doc/verify.texi (assume): Document it. * lib/verify.h (assume): New macro. (__has_builtin): Expand to 0 if not defined.

author	Paul Eggert <eggert@cs.ucla.edu>
date	Wed, 02 Oct 2013 21:59:38 -0700
parents	897fb6ccfff3
children	344018b6e5d7

rev	line source
25958 9c4f1f1fd53c * modules/verify: New file. Paul Eggert <eggert@cs.ucla.edu> parents: diff changeset	1 /* Compile-time assert-like macros.
9c4f1f1fd53c * modules/verify: New file. Paul Eggert <eggert@cs.ucla.edu> parents: diff changeset	2
36940 c741bc27922a maint: update all copyright year number ranges Eric Blake <eblake@redhat.com> parents: 36693 diff changeset	3 Copyright (C) 2005-2006, 2009-2013 Free Software Foundation, Inc.
25958 9c4f1f1fd53c * modules/verify: New file. Paul Eggert <eggert@cs.ucla.edu> parents: diff changeset	4
29000 49d1cc4454bf Change copyright notice from GPLv2+ to GPLv3+. Bruno Haible <bruno@clisp.org> parents: 26457 diff changeset	5 This program is free software: you can redistribute it and/or modify
25958 9c4f1f1fd53c * modules/verify: New file. Paul Eggert <eggert@cs.ucla.edu> parents: diff changeset	6 it under the terms of the GNU General Public License as published by
29000 49d1cc4454bf Change copyright notice from GPLv2+ to GPLv3+. Bruno Haible <bruno@clisp.org> parents: 26457 diff changeset	7 the Free Software Foundation; either version 3 of the License, or
49d1cc4454bf Change copyright notice from GPLv2+ to GPLv3+. Bruno Haible <bruno@clisp.org> parents: 26457 diff changeset	8 (at your option) any later version.
25958 9c4f1f1fd53c * modules/verify: New file. Paul Eggert <eggert@cs.ucla.edu> parents: diff changeset	9
9c4f1f1fd53c * modules/verify: New file. Paul Eggert <eggert@cs.ucla.edu> parents: diff changeset	10 This program is distributed in the hope that it will be useful,
9c4f1f1fd53c * modules/verify: New file. Paul Eggert <eggert@cs.ucla.edu> parents: diff changeset	11 but WITHOUT ANY WARRANTY; without even the implied warranty of
9c4f1f1fd53c * modules/verify: New file. Paul Eggert <eggert@cs.ucla.edu> parents: diff changeset	12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
9c4f1f1fd53c * modules/verify: New file. Paul Eggert <eggert@cs.ucla.edu> parents: diff changeset	13 GNU General Public License for more details.
9c4f1f1fd53c * modules/verify: New file. Paul Eggert <eggert@cs.ucla.edu> parents: diff changeset	14
9c4f1f1fd53c * modules/verify: New file. Paul Eggert <eggert@cs.ucla.edu> parents: diff changeset	15 You should have received a copy of the GNU General Public License
29000 49d1cc4454bf Change copyright notice from GPLv2+ to GPLv3+. Bruno Haible <bruno@clisp.org> parents: 26457 diff changeset	16 along with this program. If not, see <http://www.gnu.org/licenses/>. */
25958 9c4f1f1fd53c * modules/verify: New file. Paul Eggert <eggert@cs.ucla.edu> parents: diff changeset	17
26457 a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	18 /* Written by Paul Eggert, Bruno Haible, and Jim Meyering. */
25958 9c4f1f1fd53c * modules/verify: New file. Paul Eggert <eggert@cs.ucla.edu> parents: diff changeset	19
34389 2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	20 #ifndef _GL_VERIFY_H
37125 897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	21 #define _GL_VERIFY_H
25958 9c4f1f1fd53c * modules/verify: New file. Paul Eggert <eggert@cs.ucla.edu> parents: diff changeset	22
34389 2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	23
35930 3bcc1fcf6faf doc: C11 and C++11 are now official Paul Eggert <eggert@cs.ucla.edu> parents: 35892 diff changeset	24 /* Define _GL_HAVE__STATIC_ASSERT to 1 if _Static_assert works as per C11.
3bcc1fcf6faf doc: C11 and C++11 are now official Paul Eggert <eggert@cs.ucla.edu> parents: 35892 diff changeset	25 This is supported by GCC 4.6.0 and later, in C mode, and its use
3bcc1fcf6faf doc: C11 and C++11 are now official Paul Eggert <eggert@cs.ucla.edu> parents: 35892 diff changeset	26 here generates easier-to-read diagnostics when verify (R) fails.
34242 df82d2f841e7 verify: Fix syntax error with GCC 4.6 in C++ mode. Bruno Haible <bruno@clisp.org> parents: 34220 diff changeset	27
35930 3bcc1fcf6faf doc: C11 and C++11 are now official Paul Eggert <eggert@cs.ucla.edu> parents: 35892 diff changeset	28 Define _GL_HAVE_STATIC_ASSERT to 1 if static_assert works as per C++11.
34242 df82d2f841e7 verify: Fix syntax error with GCC 4.6 in C++ mode. Bruno Haible <bruno@clisp.org> parents: 34220 diff changeset	29 This will likely be supported by future GCC versions, in C++ mode.
34220 1cd04f034cfb verify: use _Static_assert if available Paul Eggert <eggert@cs.ucla.edu> parents: 33770 diff changeset	30
34389 2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	31 Use this only with GCC. If we were willing to slow 'configure'
2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	32 down we could also use it with other compilers, but since this
2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	33 affects only the quality of diagnostics, why bother? */
37125 897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	34 #if (4 < __GNUC__ + (6 <= __GNUC_MINOR__) \
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	35 && (201112L <= __STDC_VERSION__ \|\| !defined __STRICT_ANSI__) \
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	36 && !defined __cplusplus)
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	37 # define _GL_HAVE__STATIC_ASSERT 1
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	38 #endif
34242 df82d2f841e7 verify: Fix syntax error with GCC 4.6 in C++ mode. Bruno Haible <bruno@clisp.org> parents: 34220 diff changeset	39 /* The condition (99 < __GNUC__) is temporary, until we know about the
df82d2f841e7 verify: Fix syntax error with GCC 4.6 in C++ mode. Bruno Haible <bruno@clisp.org> parents: 34220 diff changeset	40 first G++ release that supports static_assert. */
37125 897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	41 #if (99 < __GNUC__) && defined __cplusplus
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	42 # define _GL_HAVE_STATIC_ASSERT 1
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	43 #endif
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	44
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	45 /* FreeBSD 9.1 <sys/cdefs.h>, included by <stddef.h> and lots of other
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	46 system headers, defines a conflicting _Static_assert that is no
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	47 better than ours; override it. */
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	48 #ifndef _GL_HAVE_STATIC_ASSERT
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	49 # include <stddef.h>
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	50 # undef _Static_assert
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	51 #endif
34220 1cd04f034cfb verify: use _Static_assert if available Paul Eggert <eggert@cs.ucla.edu> parents: 33770 diff changeset	52
26457 a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	53 /* Each of these macros verifies that its argument R is nonzero. To
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	54 be portable, R should be an integer constant expression. Unlike
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	55 assert (R), there is no run-time overhead.
25958 9c4f1f1fd53c * modules/verify: New file. Paul Eggert <eggert@cs.ucla.edu> parents: diff changeset	56
34220 1cd04f034cfb verify: use _Static_assert if available Paul Eggert <eggert@cs.ucla.edu> parents: 33770 diff changeset	57 If _Static_assert works, verify (R) uses it directly. Similarly,
34389 2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	58 _GL_VERIFY_TRUE works by packaging a _Static_assert inside a struct
34220 1cd04f034cfb verify: use _Static_assert if available Paul Eggert <eggert@cs.ucla.edu> parents: 33770 diff changeset	59 that is an operand of sizeof.
1cd04f034cfb verify: use _Static_assert if available Paul Eggert <eggert@cs.ucla.edu> parents: 33770 diff changeset	60
1cd04f034cfb verify: use _Static_assert if available Paul Eggert <eggert@cs.ucla.edu> parents: 33770 diff changeset	61 The code below uses several ideas for C++ compilers, and for C
1cd04f034cfb verify: use _Static_assert if available Paul Eggert <eggert@cs.ucla.edu> parents: 33770 diff changeset	62 compilers that do not support _Static_assert:
26457 a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	63
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	64 * The first step is ((R) ? 1 : -1). Given an expression R, of
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	65 integral or boolean or floating-point type, this yields an
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	66 expression of integral type, whose value is later verified to be
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	67 constant and nonnegative.
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	68
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	69 * Next this expression W is wrapped in a type
34389 2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	70 struct _gl_verify_type {
2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	71 unsigned int _gl_verify_error_if_negative: W;
2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	72 }.
26457 a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	73 If W is negative, this yields a compile-time error. No compiler can
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	74 deal with a bit-field of negative size.
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	75
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	76 One might think that an array size check would have the same
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	77 effect, that is, that the type struct { unsigned int dummy[W]; }
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	78 would work as well. However, inside a function, some compilers
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	79 (such as C++ compilers and GNU C) allow local parameters and
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	80 variables inside array size expressions. With these compilers,
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	81 an array size check would not properly diagnose this misuse of
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	82 the verify macro:
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	83
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	84 void function (int n) { verify (n < 0); }
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	85
34389 2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	86 * For the verify macro, the struct _gl_verify_type will need to
26457 a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	87 somehow be embedded into a declaration. To be portable, this
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	88 declaration must declare an object, a constant, a function, or a
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	89 typedef name. If the declared entity uses the type directly,
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	90 such as in
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	91
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	92 struct dummy {...};
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	93 typedef struct {...} dummy;
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	94 extern struct {...} *dummy;
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	95 extern void dummy (struct {...} *);
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	96 extern struct {...} *dummy (void);
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	97
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	98 two uses of the verify macro would yield colliding declarations
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	99 if the entity names are not disambiguated. A workaround is to
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	100 attach the current line number to the entity name:
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	101
33009 c655e7834a31 Further improvements to verify.h, suggested by Eric Blake. Paul Eggert <eggert@cs.ucla.edu> parents: 33008 diff changeset	102 #define _GL_CONCAT0(x, y) x##y
c655e7834a31 Further improvements to verify.h, suggested by Eric Blake. Paul Eggert <eggert@cs.ucla.edu> parents: 33008 diff changeset	103 #define _GL_CONCAT(x, y) _GL_CONCAT0 (x, y)
33016 017a59908fb0 verify: adjust formatting to be more consistent Jim Meyering <meyering@redhat.com> parents: 33009 diff changeset	104 extern struct {...} * _GL_CONCAT (dummy, __LINE__);
26457 a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	105
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	106 But this has the problem that two invocations of verify from
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	107 within the same macro would collide, since the __LINE__ value
33008 41d40ed596b7 Modify verify.h to pacify gcc -Wredundant_decls. Paul Eggert <eggert@cs.ucla.edu> parents: 32250 diff changeset	108 would be the same for both invocations. (The GCC __COUNTER__
41d40ed596b7 Modify verify.h to pacify gcc -Wredundant_decls. Paul Eggert <eggert@cs.ucla.edu> parents: 32250 diff changeset	109 macro solves this problem, but is not portable.)
26457 a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	110
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	111 A solution is to use the sizeof operator. It yields a number,
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	112 getting rid of the identity of the type. Declarations like
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	113
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	114 extern int dummy [sizeof (struct {...})];
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	115 extern void dummy (int [sizeof (struct {...})]);
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	116 extern int (*dummy (void)) [sizeof (struct {...})];
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	117
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	118 can be repeated.
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	119
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	120 * Should the implementation use a named struct or an unnamed struct?
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	121 Which of the following alternatives can be used?
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	122
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	123 extern int dummy [sizeof (struct {...})];
34389 2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	124 extern int dummy [sizeof (struct _gl_verify_type {...})];
26457 a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	125 extern void dummy (int [sizeof (struct {...})]);
34389 2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	126 extern void dummy (int [sizeof (struct _gl_verify_type {...})]);
26457 a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	127 extern int (*dummy (void)) [sizeof (struct {...})];
34389 2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	128 extern int (*dummy (void)) [sizeof (struct _gl_verify_type {...})];
26457 a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	129
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	130 In the second and sixth case, the struct type is exported to the
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	131 outer scope; two such declarations therefore collide. GCC warns
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	132 about the first, third, and fourth cases. So the only remaining
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	133 possibility is the fifth case:
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	134
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	135 extern int (*dummy (void)) [sizeof (struct {...})];
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	136
33008 41d40ed596b7 Modify verify.h to pacify gcc -Wredundant_decls. Paul Eggert <eggert@cs.ucla.edu> parents: 32250 diff changeset	137 * GCC warns about duplicate declarations of the dummy function if
36693 818a01b2b0e9 verify: document conflict with -Wnested-externs Eric Blake <eblake@redhat.com> parents: 35930 diff changeset	138 -Wredundant-decls is used. GCC 4.3 and later have a builtin
33008 41d40ed596b7 Modify verify.h to pacify gcc -Wredundant_decls. Paul Eggert <eggert@cs.ucla.edu> parents: 32250 diff changeset	139 __COUNTER__ macro that can let us generate unique identifiers for
41d40ed596b7 Modify verify.h to pacify gcc -Wredundant_decls. Paul Eggert <eggert@cs.ucla.edu> parents: 32250 diff changeset	140 each dummy function, to suppress this warning.
41d40ed596b7 Modify verify.h to pacify gcc -Wredundant_decls. Paul Eggert <eggert@cs.ucla.edu> parents: 32250 diff changeset	141
34220 1cd04f034cfb verify: use _Static_assert if available Paul Eggert <eggert@cs.ucla.edu> parents: 33770 diff changeset	142 * This implementation exploits the fact that older versions of GCC,
1cd04f034cfb verify: use _Static_assert if available Paul Eggert <eggert@cs.ucla.edu> parents: 33770 diff changeset	143 which do not support _Static_assert, also do not warn about the
1cd04f034cfb verify: use _Static_assert if available Paul Eggert <eggert@cs.ucla.edu> parents: 33770 diff changeset	144 last declaration mentioned above.
26457 a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	145
36693 818a01b2b0e9 verify: document conflict with -Wnested-externs Eric Blake <eblake@redhat.com> parents: 35930 diff changeset	146 * GCC warns if -Wnested-externs is enabled and verify() is used
818a01b2b0e9 verify: document conflict with -Wnested-externs Eric Blake <eblake@redhat.com> parents: 35930 diff changeset	147 within a function body; but inside a function, you can always
818a01b2b0e9 verify: document conflict with -Wnested-externs Eric Blake <eblake@redhat.com> parents: 35930 diff changeset	148 arrange to use verify_expr() instead.
818a01b2b0e9 verify: document conflict with -Wnested-externs Eric Blake <eblake@redhat.com> parents: 35930 diff changeset	149
26457 a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	150 * In C++, any struct definition inside sizeof is invalid.
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	151 Use a template type to work around the problem. */
a18f48244638 * doc/verify.texi: New file. Paul Eggert <eggert@cs.ucla.edu> parents: 26020 diff changeset	152
33008 41d40ed596b7 Modify verify.h to pacify gcc -Wredundant_decls. Paul Eggert <eggert@cs.ucla.edu> parents: 32250 diff changeset	153 /* Concatenate two preprocessor tokens. */
37125 897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	154 #define _GL_CONCAT(x, y) _GL_CONCAT0 (x, y)
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	155 #define _GL_CONCAT0(x, y) x##y
33008 41d40ed596b7 Modify verify.h to pacify gcc -Wredundant_decls. Paul Eggert <eggert@cs.ucla.edu> parents: 32250 diff changeset	156
33009 c655e7834a31 Further improvements to verify.h, suggested by Eric Blake. Paul Eggert <eggert@cs.ucla.edu> parents: 33008 diff changeset	157 /* _GL_COUNTER is an integer, preferably one that changes each time we
c655e7834a31 Further improvements to verify.h, suggested by Eric Blake. Paul Eggert <eggert@cs.ucla.edu> parents: 33008 diff changeset	158 use it. Use __COUNTER__ if it works, falling back on __LINE__
c655e7834a31 Further improvements to verify.h, suggested by Eric Blake. Paul Eggert <eggert@cs.ucla.edu> parents: 33008 diff changeset	159 otherwise. __LINE__ isn't perfect, but it's better than a
c655e7834a31 Further improvements to verify.h, suggested by Eric Blake. Paul Eggert <eggert@cs.ucla.edu> parents: 33008 diff changeset	160 constant. */
37125 897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	161 #if defined __COUNTER__ && __COUNTER__ != __COUNTER__
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	162 # define _GL_COUNTER __COUNTER__
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	163 #else
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	164 # define _GL_COUNTER __LINE__
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	165 #endif
33008 41d40ed596b7 Modify verify.h to pacify gcc -Wredundant_decls. Paul Eggert <eggert@cs.ucla.edu> parents: 32250 diff changeset	166
41d40ed596b7 Modify verify.h to pacify gcc -Wredundant_decls. Paul Eggert <eggert@cs.ucla.edu> parents: 32250 diff changeset	167 /* Generate a symbol with the given prefix, making it unique if
41d40ed596b7 Modify verify.h to pacify gcc -Wredundant_decls. Paul Eggert <eggert@cs.ucla.edu> parents: 32250 diff changeset	168 possible. */
37125 897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	169 #define _GL_GENSYM(prefix) _GL_CONCAT (prefix, _GL_COUNTER)
25958 9c4f1f1fd53c * modules/verify: New file. Paul Eggert <eggert@cs.ucla.edu> parents: diff changeset	170
34389 2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	171 /* Verify requirement R at compile-time, as an integer constant expression
2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	172 that returns 1. If R is false, fail at compile-time, preferably
2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	173 with a diagnostic that includes the string-literal DIAGNOSTIC. */
2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	174
37125 897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	175 #define _GL_VERIFY_TRUE(R, DIAGNOSTIC) \
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	176 (!!sizeof (_GL_VERIFY_TYPE (R, DIAGNOSTIC)))
25958 9c4f1f1fd53c * modules/verify: New file. Paul Eggert <eggert@cs.ucla.edu> parents: diff changeset	177
37125 897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	178 #ifdef __cplusplus
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	179 # if !GNULIB_defined_struct__gl_verify_type
26020 92a038cef198 * verify.h (verify_true): Provide alternative definition for C++. Paul Eggert <eggert@cs.ucla.edu> parents: 25993 diff changeset	180 template <int w>
34389 2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	181 struct _gl_verify_type {
2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	182 unsigned int _gl_verify_error_if_negative: w;
2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	183 };
37125 897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	184 # define GNULIB_defined_struct__gl_verify_type 1
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	185 # endif
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	186 # define _GL_VERIFY_TYPE(R, DIAGNOSTIC) \
34389 2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	187 _gl_verify_type<(R) ? 1 : -1>
37125 897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	188 #elif defined _GL_HAVE__STATIC_ASSERT
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	189 # define _GL_VERIFY_TYPE(R, DIAGNOSTIC) \
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	190 struct { \
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	191 _Static_assert (R, DIAGNOSTIC); \
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	192 int _gl_dummy; \
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	193 }
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	194 #else
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	195 # define _GL_VERIFY_TYPE(R, DIAGNOSTIC) \
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	196 struct { unsigned int _gl_verify_error_if_negative: (R) ? 1 : -1; }
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	197 #endif
34389 2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	198
2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	199 /* Verify requirement R at compile-time, as a declaration without a
2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	200 trailing ';'. If R is false, fail at compile-time, preferably
2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	201 with a diagnostic that includes the string-literal DIAGNOSTIC.
2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	202
35930 3bcc1fcf6faf doc: C11 and C++11 are now official Paul Eggert <eggert@cs.ucla.edu> parents: 35892 diff changeset	203 Unfortunately, unlike C11, this implementation must appear as an
34389 2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	204 ordinary declaration, and cannot appear inside struct { ... }. */
2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	205
37125 897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	206 #ifdef _GL_HAVE__STATIC_ASSERT
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	207 # define _GL_VERIFY _Static_assert
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	208 #else
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	209 # define _GL_VERIFY(R, DIAGNOSTIC) \
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	210 extern int (*_GL_GENSYM (_gl_verify_function) (void)) \
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	211 [_GL_VERIFY_TRUE (R, DIAGNOSTIC)]
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	212 #endif
25958 9c4f1f1fd53c * modules/verify: New file. Paul Eggert <eggert@cs.ucla.edu> parents: diff changeset	213
34389 2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	214 /* _GL_STATIC_ASSERT_H is defined if this code is copied into assert.h. */
37125 897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	215 #ifdef _GL_STATIC_ASSERT_H
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	216 # if !defined _GL_HAVE__STATIC_ASSERT && !defined _Static_assert
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	217 # define _Static_assert(R, DIAGNOSTIC) _GL_VERIFY (R, DIAGNOSTIC)
34490 9e4f514590d4 verify: fix bug when gnulib <assert.h> is also included Paul Eggert <eggert@cs.ucla.edu> parents: 34389 diff changeset	218 # endif
37125 897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	219 # if !defined _GL_HAVE_STATIC_ASSERT && !defined static_assert
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	220 # define static_assert _Static_assert /* C11 requires this #define. */
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	221 # endif
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	222 #endif
34490 9e4f514590d4 verify: fix bug when gnulib <assert.h> is also included Paul Eggert <eggert@cs.ucla.edu> parents: 34389 diff changeset	223
34537 8cc838add561 assert-h: work around 'verify' incompatibility Paul Eggert <eggert@cs.ucla.edu> parents: 34530 diff changeset	224 /* @assert.h omit start@ */
34389 2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	225
2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	226 /* Each of these macros verifies that its argument R is nonzero. To
2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	227 be portable, R should be an integer constant expression. Unlike
2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	228 assert (R), there is no run-time overhead.
2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	229
2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	230 There are two macros, since no single macro can be used in all
2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	231 contexts in C. verify_true (R) is for scalar contexts, including
2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	232 integer constant expression contexts. verify (R) is for declaration
2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	233 contexts, e.g., the top level. */
2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	234
2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	235 /* Verify requirement R at compile-time, as an integer constant expression.
34613 79a7919f1aa2 verify: new macro verify_expr; verify_true deprecated Paul Eggert <eggert@cs.ucla.edu> parents: 34537 diff changeset	236 Return 1. This is equivalent to verify_expr (R, 1).
79a7919f1aa2 verify: new macro verify_expr; verify_true deprecated Paul Eggert <eggert@cs.ucla.edu> parents: 34537 diff changeset	237
79a7919f1aa2 verify: new macro verify_expr; verify_true deprecated Paul Eggert <eggert@cs.ucla.edu> parents: 34537 diff changeset	238 verify_true is obsolescent; please use verify_expr instead. */
34389 2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	239
37125 897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	240 #define verify_true(R) _GL_VERIFY_TRUE (R, "verify_true (" #R ")")
34389 2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	241
34613 79a7919f1aa2 verify: new macro verify_expr; verify_true deprecated Paul Eggert <eggert@cs.ucla.edu> parents: 34537 diff changeset	242 /* Verify requirement R at compile-time. Return the value of the
79a7919f1aa2 verify: new macro verify_expr; verify_true deprecated Paul Eggert <eggert@cs.ucla.edu> parents: 34537 diff changeset	243 expression E. */
79a7919f1aa2 verify: new macro verify_expr; verify_true deprecated Paul Eggert <eggert@cs.ucla.edu> parents: 34537 diff changeset	244
37125 897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	245 #define verify_expr(R, E) \
897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	246 (_GL_VERIFY_TRUE (R, "verify_expr (" #R ", " #E ")") ? (E) : (E))
34613 79a7919f1aa2 verify: new macro verify_expr; verify_true deprecated Paul Eggert <eggert@cs.ucla.edu> parents: 34537 diff changeset	247
25993 ec0195624951 (verify_expr): Remove, replacing with: Paul Eggert <eggert@cs.ucla.edu> parents: 25981 diff changeset	248 /* Verify requirement R at compile-time, as a declaration without a
ec0195624951 (verify_expr): Remove, replacing with: Paul Eggert <eggert@cs.ucla.edu> parents: 25981 diff changeset	249 trailing ';'. */
ec0195624951 (verify_expr): Remove, replacing with: Paul Eggert <eggert@cs.ucla.edu> parents: 25981 diff changeset	250
37125 897fb6ccfff3 stdalign, verify: port to FreeBSD 9.1, to C11, and to C++11 Paul Eggert <eggert@cs.ucla.edu> parents: 37103 diff changeset	251 #define verify(R) _GL_VERIFY (R, "verify (" #R ")")
34389 2298e7e47680 assert-h: new module, which supports C1X-style static_assert Paul Eggert <eggert@cs.ucla.edu> parents: 34242 diff changeset	252
37191 2f1343191e67 verify: new macro 'assume' Paul Eggert <eggert@cs.ucla.edu> parents: 37125 diff changeset	253 #ifndef __has_builtin
2f1343191e67 verify: new macro 'assume' Paul Eggert <eggert@cs.ucla.edu> parents: 37125 diff changeset	254 # define __has_builtin(x) 0
2f1343191e67 verify: new macro 'assume' Paul Eggert <eggert@cs.ucla.edu> parents: 37125 diff changeset	255 #endif
2f1343191e67 verify: new macro 'assume' Paul Eggert <eggert@cs.ucla.edu> parents: 37125 diff changeset	256
2f1343191e67 verify: new macro 'assume' Paul Eggert <eggert@cs.ucla.edu> parents: 37125 diff changeset	257 /* Assume that R always holds. This lets the compiler optimize
2f1343191e67 verify: new macro 'assume' Paul Eggert <eggert@cs.ucla.edu> parents: 37125 diff changeset	258 accordingly. R should not have side-effects; it may or may not be
2f1343191e67 verify: new macro 'assume' Paul Eggert <eggert@cs.ucla.edu> parents: 37125 diff changeset	259 evaluated. Behavior is undefined if R is false. */
2f1343191e67 verify: new macro 'assume' Paul Eggert <eggert@cs.ucla.edu> parents: 37125 diff changeset	260
2f1343191e67 verify: new macro 'assume' Paul Eggert <eggert@cs.ucla.edu> parents: 37125 diff changeset	261 #if (__has_builtin (__builtin_unreachable) \
2f1343191e67 verify: new macro 'assume' Paul Eggert <eggert@cs.ucla.edu> parents: 37125 diff changeset	262 \|\| 4 < __GNUC__ + (5 <= __GNUC_MINOR__))
2f1343191e67 verify: new macro 'assume' Paul Eggert <eggert@cs.ucla.edu> parents: 37125 diff changeset	263 # define assume(R) ((R) ? (void) 0 : __builtin_unreachable ())
2f1343191e67 verify: new macro 'assume' Paul Eggert <eggert@cs.ucla.edu> parents: 37125 diff changeset	264 #elif 1200 <= _MSC_VER
2f1343191e67 verify: new macro 'assume' Paul Eggert <eggert@cs.ucla.edu> parents: 37125 diff changeset	265 # define assume(R) __assume (R)
2f1343191e67 verify: new macro 'assume' Paul Eggert <eggert@cs.ucla.edu> parents: 37125 diff changeset	266 #elif (defined lint \
2f1343191e67 verify: new macro 'assume' Paul Eggert <eggert@cs.ucla.edu> parents: 37125 diff changeset	267 && (__has_builtin (__builtin_trap) \
2f1343191e67 verify: new macro 'assume' Paul Eggert <eggert@cs.ucla.edu> parents: 37125 diff changeset	268 \|\| 3 < __GNUC__ + (3 < __GNUC_MINOR__ + (4 <= __GNUC_PATCHLEVEL__))))
2f1343191e67 verify: new macro 'assume' Paul Eggert <eggert@cs.ucla.edu> parents: 37125 diff changeset	269 /* Doing it this way helps various packages when configured with
2f1343191e67 verify: new macro 'assume' Paul Eggert <eggert@cs.ucla.edu> parents: 37125 diff changeset	270 --enable-gcc-warnings, which compiles with -Dlint. It's nicer
2f1343191e67 verify: new macro 'assume' Paul Eggert <eggert@cs.ucla.edu> parents: 37125 diff changeset	271 when 'assume' silences warnings even with older GCCs. */
2f1343191e67 verify: new macro 'assume' Paul Eggert <eggert@cs.ucla.edu> parents: 37125 diff changeset	272 # define assume(R) ((R) ? (void) 0 : __builtin_trap ())
2f1343191e67 verify: new macro 'assume' Paul Eggert <eggert@cs.ucla.edu> parents: 37125 diff changeset	273 #else
2f1343191e67 verify: new macro 'assume' Paul Eggert <eggert@cs.ucla.edu> parents: 37125 diff changeset	274 # define assume(R) ((void) (0 && (R)))
2f1343191e67 verify: new macro 'assume' Paul Eggert <eggert@cs.ucla.edu> parents: 37125 diff changeset	275 #endif
2f1343191e67 verify: new macro 'assume' Paul Eggert <eggert@cs.ucla.edu> parents: 37125 diff changeset	276
34537 8cc838add561 assert-h: work around 'verify' incompatibility Paul Eggert <eggert@cs.ucla.edu> parents: 34530 diff changeset	277 /* @assert.h omit end@ */
25958 9c4f1f1fd53c * modules/verify: New file. Paul Eggert <eggert@cs.ucla.edu> parents: diff changeset	278
9c4f1f1fd53c * modules/verify: New file. Paul Eggert <eggert@cs.ucla.edu> parents: diff changeset	279 #endif

Mercurial > gnulib

annotate lib/verify.h @ 37191:2f1343191e67