implement -Wempty-body and -Wignored-qualifiers and ignore some more gcc warnings
[cparser] / warning.c
1 /*
2  * This file is part of cparser.
3  * Copyright (C) 2007-2009 Matthias Braun <matze@braunis.de>
4  *
5  * This program is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU General Public License
7  * as published by the Free Software Foundation; either version 2
8  * of the License, or (at your option) any later version.
9  *
10  * This program 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
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
18  * 02111-1307, USA.
19  */
20 #include <assert.h>
21 #include <stdio.h>
22 #include <string.h>
23
24 #include "adt/util.h"
25 #include "warning.h"
26 #include "help.h"
27
28 static warning_switch_t warning[] = {
29         [WARN_ADDRESS]                       = { WARN_STATE_ON,   "address"                       },
30         [WARN_AGGREGATE_RETURN]              = { WARN_STATE_NONE, "aggregate-return"              },
31         [WARN_ATTRIBUTE]                     = { WARN_STATE_ON,   "attribute"                     },
32         [WARN_CAST_QUAL]                     = { WARN_STATE_NONE, "cast-qual",                    },
33         [WARN_CHAR_SUBSCRIPTS]               = { WARN_STATE_ON,   "char-subscripts",              },
34         [WARN_COMMENT]                       = { WARN_STATE_NONE, "comment",                      },
35         [WARN_CONVERSION]                    = { WARN_STATE_NONE, "conversion",                   },
36         [WARN_DECLARATION_AFTER_STATEMENT]   = { WARN_STATE_NONE, "declaration-after-statement",  },
37         [WARN_DEPRECATED_DECLARATIONS]       = { WARN_STATE_ON,   "deprecated-declarations",      },
38         [WARN_DIV_BY_ZERO]                   = { WARN_STATE_ON,   "div-by-zero",                  },
39         [WARN_EMPTY_BODY]                    = { WARN_STATE_NONE, "empty-body",                   },
40         [WARN_EMPTY_STATEMENT]               = { WARN_STATE_NONE, "empty-statement",              },
41         [WARN_ERROR]                         = { WARN_STATE_NONE, "error"                         },
42         [WARN_FATAL_ERRORS]                  = { WARN_STATE_NONE, "fatal-errors"                  },
43         [WARN_FLOAT_EQUAL]                   = { WARN_STATE_NONE, "float-equal",                  },
44         [WARN_FORMAT]                        = { WARN_STATE_ON,   "format"                        },
45         [WARN_IGNORED_QUALIFIERS]            = { WARN_STATE_ON,   "ignored-qualifiers"            },
46         [WARN_IMPLICIT_FUNCTION_DECLARATION] = { WARN_STATE_ON,   "implicit-function-declaration" },
47         [WARN_IMPLICIT_INT]                  = { WARN_STATE_ON,   "implicit-int"                  },
48         [WARN_LONG_LONG]                     = { WARN_STATE_NONE, "long-long"                     },
49         [WARN_MAIN]                          = { WARN_STATE_ON,   "main",                         },
50         [WARN_MISSING_DECLARATIONS]          = { WARN_STATE_NONE, "missing-declarations",         },
51         [WARN_MISSING_NORETURN]              = { WARN_STATE_NONE, "missing-noreturn",             },
52         [WARN_MISSING_PROTOTYPES]            = { WARN_STATE_NONE, "missing-prototypes",           },
53         [WARN_MULTICHAR]                     = { WARN_STATE_ON,   "multichar",                    },
54         [WARN_NESTED_EXTERNS]                = { WARN_STATE_NONE, "nested-externs"                },
55         [WARN_NONNULL]                       = { WARN_STATE_ON,   "nonnull",                      },
56         [WARN_OLD_STYLE_DEFINITION]          = { WARN_STATE_NONE, "old-style-definition",         },
57         [WARN_OTHER]                         = { WARN_STATE_ON,   "other"                         },
58         [WARN_PACKED]                        = { WARN_STATE_NONE, "packed",                       },
59         [WARN_PADDED]                        = { WARN_STATE_NONE, "padded",                       },
60         [WARN_PARENTHESES]                   = { WARN_STATE_NONE, "parentheses",                  },
61         [WARN_POINTER_ARITH]                 = { WARN_STATE_ON,   "pointer-arith",                },
62         [WARN_REDUNDANT_DECLS]               = { WARN_STATE_ON,   "redundant-decls",              },
63         [WARN_RETURN_TYPE]                   = { WARN_STATE_ON,   "return-type",                  },
64         [WARN_SHADOW]                        = { WARN_STATE_NONE, "shadow",                       },
65         [WARN_SHADOW_LOCAL]                  = { WARN_STATE_NONE, "shadow-local",                 },
66         [WARN_SIGN_COMPARE]                  = { WARN_STATE_NONE, "sign-compare",                 },
67         [WARN_STRICT_PROTOTYPES]             = { WARN_STATE_ON,   "strict-prototypes"             },
68         [WARN_SWITCH_DEFAULT]                = { WARN_STATE_NONE, "switch-default",               },
69         [WARN_SWITCH_ENUM]                   = { WARN_STATE_NONE, "switch-enum",                  },
70         [WARN_TRADITIONAL]                   = { WARN_STATE_NONE, "traditional"                   },
71         [WARN_UNINITIALIZED]                 = { WARN_STATE_ON,   "uninitialized",                },
72         [WARN_UNKNOWN_PRAGMAS]               = { WARN_STATE_ON,   "unknown-pragmas",              },
73         [WARN_UNREACHABLE_CODE]              = { WARN_STATE_NONE, "unreachable-code"              },
74         [WARN_UNUSED_FUNCTION]               = { WARN_STATE_NONE, "unused-function",              },
75         [WARN_UNUSED_LABEL]                  = { WARN_STATE_NONE, "unused-label",                 },
76         [WARN_UNUSED_PARAMETER]              = { WARN_STATE_NONE, "unused-parameter",             },
77         [WARN_UNUSED_VALUE]                  = { WARN_STATE_ON,   "unused-value",                 },
78         [WARN_UNUSED_VARIABLE]               = { WARN_STATE_NONE, "unused-variable",              },
79         [WARN_WRITE_STRINGS]                 = { WARN_STATE_NONE, "write-strings",                },
80 };
81
82 warning_switch_t const *get_warn_switch(warning_t const w)
83 {
84         assert((size_t)w < lengthof(warning));
85         assert(warning[w].name);
86         return &warning[w];
87 }
88
89 void print_warning_opt_help(void)
90 {
91         /* TODO: write explanations */
92         for (warning_switch_t* i = warning; i != endof(warning); ++i) {
93                 put_help(i->name, "");
94         }
95 }
96
97 void set_warning_opt(const char *const opt)
98 {
99         /* Process prefixes: -W[no-][error=] */
100         char const *s     = opt;
101         bool const  no    = strncmp(s, "no-",    3) == 0 ? s += 3, true : false;
102         bool const  error = strncmp(s, "error=", 6) == 0 ? s += 6, true : false;
103
104         warn_state_t on  = WARN_STATE_NONE;
105         warn_state_t off = WARN_STATE_NONE;
106         if (!no || !error)
107                 on |= WARN_STATE_ON;
108         if (error) {
109                 on  |= WARN_STATE_ERROR;
110                 off |= WARN_STATE_NO_ERROR;
111         }
112         if (no) {
113                 warn_state_t const tmp = on;
114                 on  = off;
115                 off = tmp;
116         }
117
118         for (warning_switch_t* i = warning; i != endof(warning); ++i) {
119                 if (strcmp(i->name, s) == 0) {
120                         i->state = (i->state & ~off) | on;
121                         return;
122                 }
123         }
124
125         if (s[0] == '\0') { // -W is an alias for -Wextra
126                 goto extra;
127         }
128 #define OPTX(x)   else if (strcmp(s, x) == 0)
129 #define SET(y)    (void)(warning[y].state = (warning[y].state & ~off) | on)
130         OPTX("all") {
131                 /* Note: this switched on a lot more warnings than gcc's -Wall */
132                 SET(WARN_ADDRESS);
133                 SET(WARN_ATTRIBUTE);
134                 SET(WARN_CHAR_SUBSCRIPTS);
135                 SET(WARN_COMMENT);
136                 SET(WARN_EMPTY_STATEMENT);
137                 SET(WARN_FORMAT);
138                 SET(WARN_IMPLICIT_FUNCTION_DECLARATION);
139                 SET(WARN_IMPLICIT_INT);
140                 SET(WARN_MAIN);
141                 SET(WARN_MISSING_DECLARATIONS);
142                 SET(WARN_NONNULL);
143                 SET(WARN_OTHER);
144                 SET(WARN_PARENTHESES);
145                 SET(WARN_POINTER_ARITH);
146                 SET(WARN_REDUNDANT_DECLS);
147                 SET(WARN_RETURN_TYPE);
148                 SET(WARN_SHADOW_LOCAL);
149                 SET(WARN_SIGN_COMPARE);
150                 SET(WARN_STRICT_PROTOTYPES);
151                 SET(WARN_SWITCH_ENUM);
152                 SET(WARN_UNINITIALIZED);
153                 SET(WARN_UNKNOWN_PRAGMAS);
154                 SET(WARN_UNREACHABLE_CODE);
155                 SET(WARN_UNUSED_FUNCTION);
156                 SET(WARN_UNUSED_LABEL);
157                 SET(WARN_UNUSED_PARAMETER);
158                 SET(WARN_UNUSED_VALUE);
159                 SET(WARN_UNUSED_VARIABLE);
160         }
161         OPTX("extra") {
162 extra:
163                 /* TODO */
164                 // TODO SET(function_end_without_return);
165                 SET(WARN_EMPTY_STATEMENT);
166                 // TODO SET(incomplete_aggregate_init);
167                 // TODO SET(missing_field_initializers);
168                 // TODO SET(pointless_comparison);
169                 SET(WARN_SHADOW);
170                 SET(WARN_UNUSED_PARAMETER);
171                 SET(WARN_UNUSED_VALUE);
172         }
173         OPTX("implicit") {
174                 SET(WARN_IMPLICIT_FUNCTION_DECLARATION);
175                 SET(WARN_IMPLICIT_INT);
176         }
177         OPTX("unused") {
178                 SET(WARN_UNUSED_FUNCTION);
179                 SET(WARN_UNUSED_LABEL);
180                 SET(WARN_UNUSED_PARAMETER);
181                 SET(WARN_UNUSED_VALUE);
182                 SET(WARN_UNUSED_VARIABLE);
183         }
184 #undef SET
185 #undef OPT_X
186         else if (strcmp(opt /* sic */, "error-implicit-function-declaration") == 0) {
187                 /* GCC legacy: This way it only can be activated. */
188                 warning[WARN_IMPLICIT_FUNCTION_DECLARATION].state = WARN_STATE_ON | WARN_STATE_ERROR;
189                 return;
190         }
191         else {
192                 fprintf(stderr, "warning: ignoring unknown option -W%s\n", opt);
193         }
194 }
195
196 void disable_all_warnings(void)
197 {
198         for (warning_switch_t* i = warning; i != endof(warning); ++i) {
199                 if (i != &warning[WARN_ERROR] &&
200                     i != &warning[WARN_FATAL_ERRORS]) {
201                         i->state &= ~WARN_STATE_ON;
202                 }
203         }
204 }