xref: /freebsd/contrib/tcpdump/diag-control.h (revision 02e9120893770924227138ba49df1edb3896112a)
1 /* -*- Mode: c; tab-width: 8; indent-tabs-mode: 1; c-basic-offset: 8; -*- */
2 /*
3  * Copyright (c) 1993, 1994, 1995, 1996, 1997
4  *	The Regents of the University of California.  All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. All advertising materials mentioning features or use of this software
15  *    must display the following acknowledgement:
16  *	This product includes software developed by the Computer Systems
17  *	Engineering Group at Lawrence Berkeley Laboratory.
18  * 4. Neither the name of the University nor of the Laboratory may be used
19  *    to endorse or promote products derived from this software without
20  *    specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #ifndef _diag_control_h
36 #define _diag_control_h
37 
38 #include "compiler-tests.h"
39 
40 #ifndef _MSC_VER
41   /*
42    * Clang and GCC both support this way of putting pragmas into #defines.
43    * We don't use it unless we have a compiler that supports it; the
44    * warning-suppressing pragmas differ between Clang and GCC, so we test
45    * for both of those separately.
46    */
47   #define DIAG_DO_PRAGMA(x) _Pragma (#x)
48 #endif
49 
50 /*
51  * XL C 12.1 and 13.1 for AIX require no attention in this department.
52  * XL C 16.1 defines both __GNUC__ and __clang__, so has to be tested first.
53  */
54 #if ND_IS_AT_LEAST_XL_C_VERSION(16,1)
55   /*
56    * See respective Clang note below.
57    */
58   #define DIAG_OFF_ASSIGN_ENUM \
59     DIAG_DO_PRAGMA(clang diagnostic push) \
60     DIAG_DO_PRAGMA(clang diagnostic ignored "-Wassign-enum")
61   #define DIAG_ON_ASSIGN_ENUM \
62     DIAG_DO_PRAGMA(clang diagnostic pop)
63 
64   #define DIAG_OFF_CAST_QUAL
65   #define DIAG_ON_CAST_QUAL
66   #define DIAG_OFF_DEPRECATION
67   #define DIAG_ON_DEPRECATION
68 /*
69  * The current clang compilers also define __GNUC__ and __GNUC_MINOR__
70  * thus we need to test the clang case before the GCC one
71  */
72 #elif ND_IS_AT_LEAST_CLANG_VERSION(2,8)
73   /*
74    * Clang complains if you OR together multiple enum values of a
75    * given enum type and them pass it as an argument of that enum
76    * type.  Some libcap-ng routines use enums to define bit flags;
77    * we want to squelch the warnings that produces.
78    */
79   #define DIAG_OFF_ASSIGN_ENUM \
80     DIAG_DO_PRAGMA(clang diagnostic push) \
81     DIAG_DO_PRAGMA(clang diagnostic ignored "-Wassign-enum")
82   #define DIAG_ON_ASSIGN_ENUM \
83     DIAG_DO_PRAGMA(clang diagnostic pop)
84 
85   /*
86    * It also legitimately complains about some code in the BSD
87    * getopt_long() - that code explicitly and deliberately
88    * violates the contract by permuting the argument vector
89    * (declared as char const *argv[], meaning "I won't change
90    * the vector by changing any of its elements), as do the
91    * GNU and Solaris getopt_long().  This is documented in the
92    * man pages for all versions; it can be suppressed by setting
93    * the environment variable POSIXLY_CORRECT or by putting a "+"
94    * at the beginning of the option string.
95    *
96    * We suppress the warning.
97    */
98   #define DIAG_OFF_CAST_QUAL \
99     DIAG_DO_PRAGMA(clang diagnostic push) \
100     DIAG_DO_PRAGMA(clang diagnostic ignored "-Wcast-qual")
101   #define DIAG_ON_CAST_QUAL \
102     DIAG_DO_PRAGMA(clang diagnostic pop)
103 
104   /*
105    * Suppress deprecation warnings.
106    */
107   #define DIAG_OFF_DEPRECATION \
108     DIAG_DO_PRAGMA(clang diagnostic push) \
109     DIAG_DO_PRAGMA(clang diagnostic ignored "-Wdeprecated-declarations")
110   #define DIAG_ON_DEPRECATION \
111     DIAG_DO_PRAGMA(clang diagnostic pop)
112 
113   /*
114    * Clang supports the generic C11 extension even if run with the -std=gnu99
115    * flag, which leads FreeBSD <sys/cdefs.h> to use the extension, which
116    * results in Clang emitting a -Wc11-extensions warning. The warning is not
117    * documented in the user manual, but it happens with Clang 10.0.1 on
118    * FreeBSD 12.2, so let's use that as a reference.
119    */
120   #if ND_IS_AT_LEAST_CLANG_VERSION(10,0)
121     #define DIAG_OFF_C11_EXTENSIONS \
122       DIAG_DO_PRAGMA(clang diagnostic push) \
123       DIAG_DO_PRAGMA(clang diagnostic ignored "-Wc11-extensions")
124     #define DIAG_ON_C11_EXTENSIONS \
125       DIAG_DO_PRAGMA(clang diagnostic pop)
126   #endif
127 #elif ND_IS_AT_LEAST_GNUC_VERSION(4,2)
128   /* GCC apparently doesn't complain about ORing enums together. */
129   #define DIAG_OFF_ASSIGN_ENUM
130   #define DIAG_ON_ASSIGN_ENUM
131 
132   /*
133    * It does, however, complain about casting away constness in
134    * missing/getopt_long.c.
135    */
136   #define DIAG_OFF_CAST_QUAL \
137     DIAG_DO_PRAGMA(GCC diagnostic push) \
138     DIAG_DO_PRAGMA(GCC diagnostic ignored "-Wcast-qual")
139   #define DIAG_ON_CAST_QUAL \
140     DIAG_DO_PRAGMA(GCC diagnostic pop)
141 
142   /*
143    * Suppress deprecation warnings.
144    */
145   #define DIAG_OFF_DEPRECATION \
146     DIAG_DO_PRAGMA(GCC diagnostic push) \
147     DIAG_DO_PRAGMA(GCC diagnostic ignored "-Wdeprecated-declarations")
148   #define DIAG_ON_DEPRECATION \
149     DIAG_DO_PRAGMA(GCC diagnostic pop)
150   /*
151    * GCC supports -Wc99-c11-compat since version 5.1.0, but the warning does
152    * not trigger for now, so let's just leave it be.
153    */
154 #else
155   #define DIAG_OFF_ASSIGN_ENUM
156   #define DIAG_ON_ASSIGN_ENUM
157   #define DIAG_OFF_CAST_QUAL
158   #define DIAG_ON_CAST_QUAL
159   #define DIAG_OFF_DEPRECATION
160   #define DIAG_ON_DEPRECATION
161 #endif
162 
163 #ifndef DIAG_OFF_C11_EXTENSIONS
164 #define DIAG_OFF_C11_EXTENSIONS
165 #endif
166 #ifndef DIAG_ON_C11_EXTENSIONS
167 #define DIAG_ON_C11_EXTENSIONS
168 #endif
169 
170 /*
171  * GCC needs this on AIX for longjmp().
172  */
173 #if ND_IS_AT_LEAST_GNUC_VERSION(5,1)
174   /*
175    * Beware that the effect of this builtin is more than just squelching the
176    * warning! GCC trusts it enough for the process to segfault if the control
177    * flow reaches the builtin (an infinite empty loop in the same context would
178    * squelch the warning and ruin the process too, albeit in a different way).
179    * So please remember to use this very carefully.
180    */
181   #define ND_UNREACHABLE __builtin_unreachable();
182 #else
183   #define ND_UNREACHABLE
184 #endif
185 
186 #endif /* _diag_control_h */
187