]>
Commit | Line | Data |
---|---|---|
e15f7de6 | 1 | /* Macros for controlling diagnostic output from the compiler. |
dff8da6b | 2 | Copyright (C) 2014-2024 Free Software Foundation, Inc. |
e15f7de6 ZW |
3 | This file is part of the GNU C Library. |
4 | ||
5 | The GNU C Library is free software; you can redistribute it and/or | |
6 | modify it under the terms of the GNU Lesser General Public | |
7 | License as published by the Free Software Foundation; either | |
8 | version 2.1 of the License, or (at your option) any later version. | |
9 | ||
10 | The GNU C Library is distributed in the hope that it will be useful, | |
11 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
13 | Lesser General Public License for more details. | |
14 | ||
15 | You should have received a copy of the GNU Lesser General Public | |
16 | License along with the GNU C Library; if not, see | |
5a82c748 | 17 | <https://www.gnu.org/licenses/>. */ |
e15f7de6 ZW |
18 | |
19 | #ifndef _LIBC_DIAG_H | |
20 | #define _LIBC_DIAG_H 1 | |
21 | ||
22 | /* Ignore the value of an expression when a cast to void does not | |
23 | suffice (in particular, for a call to a function declared with | |
24 | attribute warn_unused_result). */ | |
25 | #define ignore_value(x) \ | |
26 | ({ __typeof__ (x) __ignored_value = (x); (void) __ignored_value; }) | |
27 | ||
28 | /* The macros to control diagnostics are structured like this, rather | |
29 | than a single macro that both pushes and pops diagnostic state and | |
30 | takes the affected code as an argument, because the GCC pragmas | |
31 | work by disabling the diagnostic for a range of source locations | |
32 | and do not work when all the pragmas and the affected code are in a | |
33 | single macro expansion. */ | |
34 | ||
35 | /* Push diagnostic state. */ | |
36 | #define DIAG_PUSH_NEEDS_COMMENT _Pragma ("GCC diagnostic push") | |
37 | ||
38 | /* Pop diagnostic state. */ | |
39 | #define DIAG_POP_NEEDS_COMMENT _Pragma ("GCC diagnostic pop") | |
40 | ||
41 | #define _DIAG_STR1(s) #s | |
42 | #define _DIAG_STR(s) _DIAG_STR1(s) | |
43 | ||
44 | /* Ignore the diagnostic OPTION. VERSION is the most recent GCC | |
45 | version for which the diagnostic has been confirmed to appear in | |
46 | the absence of the pragma (in the form MAJOR.MINOR for GCC 4.x, | |
47 | just MAJOR for GCC 5 and later). Uses of this pragma should be | |
48 | reviewed when the GCC version given is no longer supported for | |
49 | building glibc; the version number should always be on the same | |
50 | source line as the macro name, so such uses can be found with grep. | |
51 | Uses should come with a comment giving more details of the | |
52 | diagnostic, and an architecture on which it is seen if possibly | |
53 | optimization-related and not in architecture-specific code. This | |
54 | macro should only be used if the diagnostic seems hard to fix (for | |
55 | example, optimization-related false positives). */ | |
56 | #define DIAG_IGNORE_NEEDS_COMMENT(version, option) \ | |
57 | _Pragma (_DIAG_STR (GCC diagnostic ignored option)) | |
58 | ||
59 | /* Similar to DIAG_IGNORE_NEEDS_COMMENT the following macro ignores the | |
60 | diagnostic OPTION but only if optimizations for size are enabled. | |
61 | This is required because different warnings may be generated for | |
62 | different optimization levels. For example a key piece of code may | |
63 | only generate a warning when compiled at -Os, but at -O2 you could | |
64 | still want the warning to be enabled to catch errors. In this case | |
65 | you would use DIAG_IGNORE_Os_NEEDS_COMMENT to disable the warning | |
66 | only for -Os. */ | |
67 | #ifdef __OPTIMIZE_SIZE__ | |
68 | # define DIAG_IGNORE_Os_NEEDS_COMMENT(version, option) \ | |
69 | _Pragma (_DIAG_STR (GCC diagnostic ignored option)) | |
70 | #else | |
71 | # define DIAG_IGNORE_Os_NEEDS_COMMENT(version, option) | |
72 | #endif | |
73 | ||
74 | #endif /* libc-diag.h */ |