| 1 | # -*- buffer-read-only: t -*- |
| 2 | # !!!!!!! DO NOT EDIT THIS FILE !!!!!!! |
| 3 | # This file is built by regen/warnings.pl. |
| 4 | # Any changes made here will be lost! |
| 5 | |
| 6 | package warnings; |
| 7 | |
| 8 | our $VERSION = "1.39"; |
| 9 | |
| 10 | # Verify that we're called correctly so that warnings will work. |
| 11 | # Can't use Carp, since Carp uses us! |
| 12 | # String regexps because constant folding = smaller optree = less memory vs regexp literal |
| 13 | # see also strict.pm. |
| 14 | die sprintf "Incorrect use of pragma '%s' at %s line %d.\n", __PACKAGE__, +(caller)[1,2] |
| 15 | if __FILE__ !~ ( '(?x) \b '.__PACKAGE__.' \.pmc? \z' ) |
| 16 | && __FILE__ =~ ( '(?x) \b (?i:'.__PACKAGE__.') \.pmc? \z' ); |
| 17 | |
| 18 | our %Offsets = ( |
| 19 | # Warnings Categories added in Perl 5.008 |
| 20 | 'all' => 0, |
| 21 | 'closure' => 2, |
| 22 | 'deprecated' => 4, |
| 23 | 'exiting' => 6, |
| 24 | 'glob' => 8, |
| 25 | 'io' => 10, |
| 26 | 'closed' => 12, |
| 27 | 'exec' => 14, |
| 28 | 'layer' => 16, |
| 29 | 'newline' => 18, |
| 30 | 'pipe' => 20, |
| 31 | 'unopened' => 22, |
| 32 | 'misc' => 24, |
| 33 | 'numeric' => 26, |
| 34 | 'once' => 28, |
| 35 | 'overflow' => 30, |
| 36 | 'pack' => 32, |
| 37 | 'portable' => 34, |
| 38 | 'recursion' => 36, |
| 39 | 'redefine' => 38, |
| 40 | 'regexp' => 40, |
| 41 | 'severe' => 42, |
| 42 | 'debugging' => 44, |
| 43 | 'inplace' => 46, |
| 44 | 'internal' => 48, |
| 45 | 'malloc' => 50, |
| 46 | 'signal' => 52, |
| 47 | 'substr' => 54, |
| 48 | 'syntax' => 56, |
| 49 | 'ambiguous' => 58, |
| 50 | 'bareword' => 60, |
| 51 | 'digit' => 62, |
| 52 | 'parenthesis' => 64, |
| 53 | 'precedence' => 66, |
| 54 | 'printf' => 68, |
| 55 | 'prototype' => 70, |
| 56 | 'qw' => 72, |
| 57 | 'reserved' => 74, |
| 58 | 'semicolon' => 76, |
| 59 | 'taint' => 78, |
| 60 | 'threads' => 80, |
| 61 | 'uninitialized' => 82, |
| 62 | 'unpack' => 84, |
| 63 | 'untie' => 86, |
| 64 | 'utf8' => 88, |
| 65 | 'void' => 90, |
| 66 | |
| 67 | # Warnings Categories added in Perl 5.011 |
| 68 | 'imprecision' => 92, |
| 69 | 'illegalproto' => 94, |
| 70 | |
| 71 | # Warnings Categories added in Perl 5.013 |
| 72 | 'non_unicode' => 96, |
| 73 | 'nonchar' => 98, |
| 74 | 'surrogate' => 100, |
| 75 | |
| 76 | # Warnings Categories added in Perl 5.017 |
| 77 | 'experimental' => 102, |
| 78 | 'experimental::lexical_subs' => 104, |
| 79 | 'experimental::regex_sets' => 106, |
| 80 | 'experimental::smartmatch' => 108, |
| 81 | |
| 82 | # Warnings Categories added in Perl 5.019 |
| 83 | 'experimental::postderef' => 110, |
| 84 | 'experimental::signatures' => 112, |
| 85 | 'syscalls' => 114, |
| 86 | |
| 87 | # Warnings Categories added in Perl 5.021 |
| 88 | 'experimental::bitwise' => 116, |
| 89 | 'experimental::const_attr' => 118, |
| 90 | 'experimental::re_strict' => 120, |
| 91 | 'experimental::refaliasing' => 122, |
| 92 | 'experimental::win32_perlio' => 124, |
| 93 | 'locale' => 126, |
| 94 | 'missing' => 128, |
| 95 | 'redundant' => 130, |
| 96 | |
| 97 | # Warnings Categories added in Perl 5.025 |
| 98 | 'experimental::declared_refs' => 132, |
| 99 | |
| 100 | # Warnings Categories added in Perl 5.027 |
| 101 | 'shadow' => 134, |
| 102 | ); |
| 103 | |
| 104 | our %Bits = ( |
| 105 | 'all' => "\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55", # [0..67] |
| 106 | 'ambiguous' => "\x00\x00\x00\x00\x00\x00\x00\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [29] |
| 107 | 'bareword' => "\x00\x00\x00\x00\x00\x00\x00\x10\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [30] |
| 108 | 'closed' => "\x00\x10\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [6] |
| 109 | 'closure' => "\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [1] |
| 110 | 'debugging' => "\x00\x00\x00\x00\x00\x10\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [22] |
| 111 | 'deprecated' => "\x10\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [2] |
| 112 | 'digit' => "\x00\x00\x00\x00\x00\x00\x00\x40\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [31] |
| 113 | 'exec' => "\x00\x40\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [7] |
| 114 | 'exiting' => "\x40\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [3] |
| 115 | 'experimental' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x40\x55\x51\x15\x10", # [51..56,58..62,66] |
| 116 | 'experimental::bitwise' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x10\x00\x00", # [58] |
| 117 | 'experimental::const_attr' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x40\x00\x00", # [59] |
| 118 | 'experimental::declared_refs' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x10", # [66] |
| 119 | 'experimental::lexical_subs' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00", # [52] |
| 120 | 'experimental::postderef' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x40\x00\x00\x00", # [55] |
| 121 | 'experimental::re_strict' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00", # [60] |
| 122 | 'experimental::refaliasing' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x04\x00", # [61] |
| 123 | 'experimental::regex_sets' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x04\x00\x00\x00", # [53] |
| 124 | 'experimental::signatures' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00", # [56] |
| 125 | 'experimental::smartmatch' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x10\x00\x00\x00", # [54] |
| 126 | 'experimental::win32_perlio' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x10\x00", # [62] |
| 127 | 'glob' => "\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [4] |
| 128 | 'illegalproto' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x40\x00\x00\x00\x00\x00", # [47] |
| 129 | 'imprecision' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x10\x00\x00\x00\x00\x00", # [46] |
| 130 | 'inplace' => "\x00\x00\x00\x00\x00\x40\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [23] |
| 131 | 'internal' => "\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [24] |
| 132 | 'io' => "\x00\x54\x55\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x04\x00\x00", # [5..11,57] |
| 133 | 'layer' => "\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [8] |
| 134 | 'locale' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x40\x00", # [63] |
| 135 | 'malloc' => "\x00\x00\x00\x00\x00\x00\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [25] |
| 136 | 'misc' => "\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [12] |
| 137 | 'missing' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01", # [64] |
| 138 | 'newline' => "\x00\x00\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [9] |
| 139 | 'non_unicode' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00", # [48] |
| 140 | 'nonchar' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x04\x00\x00\x00\x00", # [49] |
| 141 | 'numeric' => "\x00\x00\x00\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [13] |
| 142 | 'once' => "\x00\x00\x00\x10\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [14] |
| 143 | 'overflow' => "\x00\x00\x00\x40\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [15] |
| 144 | 'pack' => "\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [16] |
| 145 | 'parenthesis' => "\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00", # [32] |
| 146 | 'pipe' => "\x00\x00\x10\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [10] |
| 147 | 'portable' => "\x00\x00\x00\x00\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [17] |
| 148 | 'precedence' => "\x00\x00\x00\x00\x00\x00\x00\x00\x04\x00\x00\x00\x00\x00\x00\x00\x00", # [33] |
| 149 | 'printf' => "\x00\x00\x00\x00\x00\x00\x00\x00\x10\x00\x00\x00\x00\x00\x00\x00\x00", # [34] |
| 150 | 'prototype' => "\x00\x00\x00\x00\x00\x00\x00\x00\x40\x00\x00\x00\x00\x00\x00\x00\x00", # [35] |
| 151 | 'qw' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00", # [36] |
| 152 | 'recursion' => "\x00\x00\x00\x00\x10\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [18] |
| 153 | 'redefine' => "\x00\x00\x00\x00\x40\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [19] |
| 154 | 'redundant' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x04", # [65] |
| 155 | 'regexp' => "\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [20] |
| 156 | 'reserved' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x04\x00\x00\x00\x00\x00\x00\x00", # [37] |
| 157 | 'semicolon' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x10\x00\x00\x00\x00\x00\x00\x00", # [38] |
| 158 | 'severe' => "\x00\x00\x00\x00\x00\x54\x05\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [21..25] |
| 159 | 'shadow' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x40", # [67] |
| 160 | 'signal' => "\x00\x00\x00\x00\x00\x00\x10\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [26] |
| 161 | 'substr' => "\x00\x00\x00\x00\x00\x00\x40\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [27] |
| 162 | 'surrogate' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x10\x00\x00\x00\x00", # [50] |
| 163 | 'syntax' => "\x00\x00\x00\x00\x00\x00\x00\x55\x55\x15\x00\x40\x00\x00\x00\x00\x00", # [28..38,47] |
| 164 | 'syscalls' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x04\x00\x00", # [57] |
| 165 | 'taint' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x40\x00\x00\x00\x00\x00\x00\x00", # [39] |
| 166 | 'threads' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00", # [40] |
| 167 | 'uninitialized' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x04\x00\x00\x00\x00\x00\x00", # [41] |
| 168 | 'unopened' => "\x00\x00\x40\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [11] |
| 169 | 'unpack' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x10\x00\x00\x00\x00\x00\x00", # [42] |
| 170 | 'untie' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x40\x00\x00\x00\x00\x00\x00", # [43] |
| 171 | 'utf8' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x15\x00\x00\x00\x00", # [44,48..50] |
| 172 | 'void' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x04\x00\x00\x00\x00\x00", # [45] |
| 173 | ); |
| 174 | |
| 175 | our %DeadBits = ( |
| 176 | 'all' => "\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa", # [0..67] |
| 177 | 'ambiguous' => "\x00\x00\x00\x00\x00\x00\x00\x08\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [29] |
| 178 | 'bareword' => "\x00\x00\x00\x00\x00\x00\x00\x20\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [30] |
| 179 | 'closed' => "\x00\x20\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [6] |
| 180 | 'closure' => "\x08\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [1] |
| 181 | 'debugging' => "\x00\x00\x00\x00\x00\x20\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [22] |
| 182 | 'deprecated' => "\x20\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [2] |
| 183 | 'digit' => "\x00\x00\x00\x00\x00\x00\x00\x80\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [31] |
| 184 | 'exec' => "\x00\x80\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [7] |
| 185 | 'exiting' => "\x80\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [3] |
| 186 | 'experimental' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x80\xaa\xa2\x2a\x20", # [51..56,58..62,66] |
| 187 | 'experimental::bitwise' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x20\x00\x00", # [58] |
| 188 | 'experimental::const_attr' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x80\x00\x00", # [59] |
| 189 | 'experimental::declared_refs' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x20", # [66] |
| 190 | 'experimental::lexical_subs' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x00\x00", # [52] |
| 191 | 'experimental::postderef' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x80\x00\x00\x00", # [55] |
| 192 | 'experimental::re_strict' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00", # [60] |
| 193 | 'experimental::refaliasing' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x08\x00", # [61] |
| 194 | 'experimental::regex_sets' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x08\x00\x00\x00", # [53] |
| 195 | 'experimental::signatures' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x00", # [56] |
| 196 | 'experimental::smartmatch' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x20\x00\x00\x00", # [54] |
| 197 | 'experimental::win32_perlio' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x20\x00", # [62] |
| 198 | 'glob' => "\x00\x02\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [4] |
| 199 | 'illegalproto' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x80\x00\x00\x00\x00\x00", # [47] |
| 200 | 'imprecision' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x20\x00\x00\x00\x00\x00", # [46] |
| 201 | 'inplace' => "\x00\x00\x00\x00\x00\x80\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [23] |
| 202 | 'internal' => "\x00\x00\x00\x00\x00\x00\x02\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [24] |
| 203 | 'io' => "\x00\xa8\xaa\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x08\x00\x00", # [5..11,57] |
| 204 | 'layer' => "\x00\x00\x02\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [8] |
| 205 | 'locale' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x80\x00", # [63] |
| 206 | 'malloc' => "\x00\x00\x00\x00\x00\x00\x08\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [25] |
| 207 | 'misc' => "\x00\x00\x00\x02\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [12] |
| 208 | 'missing' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02", # [64] |
| 209 | 'newline' => "\x00\x00\x08\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [9] |
| 210 | 'non_unicode' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x00\x00\x00", # [48] |
| 211 | 'nonchar' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x08\x00\x00\x00\x00", # [49] |
| 212 | 'numeric' => "\x00\x00\x00\x08\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [13] |
| 213 | 'once' => "\x00\x00\x00\x20\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [14] |
| 214 | 'overflow' => "\x00\x00\x00\x80\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [15] |
| 215 | 'pack' => "\x00\x00\x00\x00\x02\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [16] |
| 216 | 'parenthesis' => "\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x00\x00\x00\x00\x00\x00\x00", # [32] |
| 217 | 'pipe' => "\x00\x00\x20\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [10] |
| 218 | 'portable' => "\x00\x00\x00\x00\x08\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [17] |
| 219 | 'precedence' => "\x00\x00\x00\x00\x00\x00\x00\x00\x08\x00\x00\x00\x00\x00\x00\x00\x00", # [33] |
| 220 | 'printf' => "\x00\x00\x00\x00\x00\x00\x00\x00\x20\x00\x00\x00\x00\x00\x00\x00\x00", # [34] |
| 221 | 'prototype' => "\x00\x00\x00\x00\x00\x00\x00\x00\x80\x00\x00\x00\x00\x00\x00\x00\x00", # [35] |
| 222 | 'qw' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x00\x00\x00\x00\x00\x00", # [36] |
| 223 | 'recursion' => "\x00\x00\x00\x00\x20\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [18] |
| 224 | 'redefine' => "\x00\x00\x00\x00\x80\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [19] |
| 225 | 'redundant' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x08", # [65] |
| 226 | 'regexp' => "\x00\x00\x00\x00\x00\x02\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [20] |
| 227 | 'reserved' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x08\x00\x00\x00\x00\x00\x00\x00", # [37] |
| 228 | 'semicolon' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x20\x00\x00\x00\x00\x00\x00\x00", # [38] |
| 229 | 'severe' => "\x00\x00\x00\x00\x00\xa8\x0a\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [21..25] |
| 230 | 'shadow' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x80", # [67] |
| 231 | 'signal' => "\x00\x00\x00\x00\x00\x00\x20\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [26] |
| 232 | 'substr' => "\x00\x00\x00\x00\x00\x00\x80\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [27] |
| 233 | 'surrogate' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x20\x00\x00\x00\x00", # [50] |
| 234 | 'syntax' => "\x00\x00\x00\x00\x00\x00\x00\xaa\xaa\x2a\x00\x80\x00\x00\x00\x00\x00", # [28..38,47] |
| 235 | 'syscalls' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x08\x00\x00", # [57] |
| 236 | 'taint' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x80\x00\x00\x00\x00\x00\x00\x00", # [39] |
| 237 | 'threads' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x00\x00\x00\x00\x00", # [40] |
| 238 | 'uninitialized' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x08\x00\x00\x00\x00\x00\x00", # [41] |
| 239 | 'unopened' => "\x00\x00\x80\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", # [11] |
| 240 | 'unpack' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x20\x00\x00\x00\x00\x00\x00", # [42] |
| 241 | 'untie' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x80\x00\x00\x00\x00\x00\x00", # [43] |
| 242 | 'utf8' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x2a\x00\x00\x00\x00", # [44,48..50] |
| 243 | 'void' => "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x08\x00\x00\x00\x00\x00", # [45] |
| 244 | ); |
| 245 | |
| 246 | # These are used by various things, including our own tests |
| 247 | our $NONE = "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"; |
| 248 | our $DEFAULT = "\x10\x01\x00\x00\x00\x50\x04\x00\x00\x00\x00\x00\x00\x55\x51\x55\x10", # [2,4,22,23,25,52..56,58..63,66] |
| 249 | our $LAST_BIT = 136 ; |
| 250 | our $BYTES = 17 ; |
| 251 | |
| 252 | sub Croaker |
| 253 | { |
| 254 | require Carp; # this initializes %CarpInternal |
| 255 | local $Carp::CarpInternal{'warnings'}; |
| 256 | delete $Carp::CarpInternal{'warnings'}; |
| 257 | Carp::croak(@_); |
| 258 | } |
| 259 | |
| 260 | sub _expand_bits { |
| 261 | my $bits = shift; |
| 262 | my $want_len = ($LAST_BIT + 7) >> 3; |
| 263 | my $len = length($bits); |
| 264 | if ($len != $want_len) { |
| 265 | if ($bits eq "") { |
| 266 | $bits = "\x00" x $want_len; |
| 267 | } elsif ($len > $want_len) { |
| 268 | substr $bits, $want_len, $len-$want_len, ""; |
| 269 | } else { |
| 270 | my $a = vec($bits, $Offsets{all} >> 1, 2); |
| 271 | $a |= $a << 2; |
| 272 | $a |= $a << 4; |
| 273 | $bits .= chr($a) x ($want_len - $len); |
| 274 | } |
| 275 | } |
| 276 | return $bits; |
| 277 | } |
| 278 | |
| 279 | sub _bits { |
| 280 | my $mask = shift ; |
| 281 | my $catmask ; |
| 282 | my $fatal = 0 ; |
| 283 | my $no_fatal = 0 ; |
| 284 | |
| 285 | $mask = _expand_bits($mask); |
| 286 | foreach my $word ( @_ ) { |
| 287 | if ($word eq 'FATAL') { |
| 288 | $fatal = 1; |
| 289 | $no_fatal = 0; |
| 290 | } |
| 291 | elsif ($word eq 'NONFATAL') { |
| 292 | $fatal = 0; |
| 293 | $no_fatal = 1; |
| 294 | } |
| 295 | elsif ($catmask = $Bits{$word}) { |
| 296 | $mask |= $catmask ; |
| 297 | $mask |= $DeadBits{$word} if $fatal ; |
| 298 | $mask = ~(~$mask | $DeadBits{$word}) if $no_fatal ; |
| 299 | } |
| 300 | else |
| 301 | { Croaker("Unknown warnings category '$word'")} |
| 302 | } |
| 303 | |
| 304 | return $mask ; |
| 305 | } |
| 306 | |
| 307 | sub bits |
| 308 | { |
| 309 | # called from B::Deparse.pm |
| 310 | push @_, 'all' unless @_ ; |
| 311 | return _bits("", @_) ; |
| 312 | } |
| 313 | |
| 314 | sub import |
| 315 | { |
| 316 | shift; |
| 317 | |
| 318 | my $mask = ${^WARNING_BITS} // ($^W ? $Bits{all} : $DEFAULT) ; |
| 319 | |
| 320 | # append 'all' when implied (empty import list or after a lone |
| 321 | # "FATAL" or "NONFATAL") |
| 322 | push @_, 'all' |
| 323 | if !@_ || (@_==1 && ($_[0] eq 'FATAL' || $_[0] eq 'NONFATAL')); |
| 324 | |
| 325 | ${^WARNING_BITS} = _bits($mask, @_); |
| 326 | } |
| 327 | |
| 328 | sub unimport |
| 329 | { |
| 330 | shift; |
| 331 | |
| 332 | my $catmask ; |
| 333 | my $mask = ${^WARNING_BITS} // ($^W ? $Bits{all} : $DEFAULT) ; |
| 334 | |
| 335 | # append 'all' when implied (empty import list or after a lone "FATAL") |
| 336 | push @_, 'all' if !@_ || @_==1 && $_[0] eq 'FATAL'; |
| 337 | |
| 338 | $mask = _expand_bits($mask); |
| 339 | foreach my $word ( @_ ) { |
| 340 | if ($word eq 'FATAL') { |
| 341 | next; |
| 342 | } |
| 343 | elsif ($catmask = $Bits{$word}) { |
| 344 | $mask = ~(~$mask | $catmask | $DeadBits{$word}); |
| 345 | } |
| 346 | else |
| 347 | { Croaker("Unknown warnings category '$word'")} |
| 348 | } |
| 349 | |
| 350 | ${^WARNING_BITS} = $mask ; |
| 351 | } |
| 352 | |
| 353 | my %builtin_type; @builtin_type{qw(SCALAR ARRAY HASH CODE REF GLOB LVALUE Regexp)} = (); |
| 354 | |
| 355 | sub MESSAGE () { 4 }; |
| 356 | sub FATAL () { 2 }; |
| 357 | sub NORMAL () { 1 }; |
| 358 | |
| 359 | sub __chk |
| 360 | { |
| 361 | my $category ; |
| 362 | my $offset ; |
| 363 | my $isobj = 0 ; |
| 364 | my $wanted = shift; |
| 365 | my $has_message = $wanted & MESSAGE; |
| 366 | |
| 367 | unless (@_ == 1 || @_ == ($has_message ? 2 : 0)) { |
| 368 | my $sub = (caller 1)[3]; |
| 369 | my $syntax = $has_message ? "[category,] 'message'" : '[category]'; |
| 370 | Croaker("Usage: $sub($syntax)"); |
| 371 | } |
| 372 | |
| 373 | my $message = pop if $has_message; |
| 374 | |
| 375 | if (@_) { |
| 376 | # check the category supplied. |
| 377 | $category = shift ; |
| 378 | if (my $type = ref $category) { |
| 379 | Croaker("not an object") |
| 380 | if exists $builtin_type{$type}; |
| 381 | $category = $type; |
| 382 | $isobj = 1 ; |
| 383 | } |
| 384 | $offset = $Offsets{$category}; |
| 385 | Croaker("Unknown warnings category '$category'") |
| 386 | unless defined $offset; |
| 387 | } |
| 388 | else { |
| 389 | $category = (caller(1))[0] ; |
| 390 | $offset = $Offsets{$category}; |
| 391 | Croaker("package '$category' not registered for warnings") |
| 392 | unless defined $offset ; |
| 393 | } |
| 394 | |
| 395 | my $i; |
| 396 | |
| 397 | if ($isobj) { |
| 398 | my $pkg; |
| 399 | $i = 2; |
| 400 | while (do { { package DB; $pkg = (caller($i++))[0] } } ) { |
| 401 | last unless @DB::args && $DB::args[0] =~ /^$category=/ ; |
| 402 | } |
| 403 | $i -= 2 ; |
| 404 | } |
| 405 | else { |
| 406 | $i = _error_loc(); # see where Carp will allocate the error |
| 407 | } |
| 408 | |
| 409 | # Default to 0 if caller returns nothing. Default to $DEFAULT if it |
| 410 | # explicitly returns undef. |
| 411 | my(@callers_bitmask) = (caller($i))[9] ; |
| 412 | my $callers_bitmask = |
| 413 | @callers_bitmask ? $callers_bitmask[0] // $DEFAULT : 0 ; |
| 414 | length($callers_bitmask) > ($offset >> 3) or $offset = $Offsets{all}; |
| 415 | |
| 416 | my @results; |
| 417 | foreach my $type (FATAL, NORMAL) { |
| 418 | next unless $wanted & $type; |
| 419 | |
| 420 | push @results, vec($callers_bitmask, $offset + $type - 1, 1); |
| 421 | } |
| 422 | |
| 423 | # &enabled and &fatal_enabled |
| 424 | return $results[0] unless $has_message; |
| 425 | |
| 426 | # &warnif, and the category is neither enabled as warning nor as fatal |
| 427 | return if $wanted == (NORMAL | FATAL | MESSAGE) |
| 428 | && !($results[0] || $results[1]); |
| 429 | |
| 430 | require Carp; |
| 431 | Carp::croak($message) if $results[0]; |
| 432 | # will always get here for &warn. will only get here for &warnif if the |
| 433 | # category is enabled |
| 434 | Carp::carp($message); |
| 435 | } |
| 436 | |
| 437 | sub _mkMask |
| 438 | { |
| 439 | my ($bit) = @_; |
| 440 | my $mask = ""; |
| 441 | |
| 442 | vec($mask, $bit, 1) = 1; |
| 443 | return $mask; |
| 444 | } |
| 445 | |
| 446 | sub register_categories |
| 447 | { |
| 448 | my @names = @_; |
| 449 | |
| 450 | for my $name (@names) { |
| 451 | if (! defined $Bits{$name}) { |
| 452 | $Offsets{$name} = $LAST_BIT; |
| 453 | $Bits{$name} = _mkMask($LAST_BIT++); |
| 454 | $DeadBits{$name} = _mkMask($LAST_BIT++); |
| 455 | if (length($Bits{$name}) > length($Bits{all})) { |
| 456 | $Bits{all} .= "\x55"; |
| 457 | $DeadBits{all} .= "\xaa"; |
| 458 | } |
| 459 | } |
| 460 | } |
| 461 | } |
| 462 | |
| 463 | sub _error_loc { |
| 464 | require Carp; |
| 465 | goto &Carp::short_error_loc; # don't introduce another stack frame |
| 466 | } |
| 467 | |
| 468 | sub enabled |
| 469 | { |
| 470 | return __chk(NORMAL, @_); |
| 471 | } |
| 472 | |
| 473 | sub fatal_enabled |
| 474 | { |
| 475 | return __chk(FATAL, @_); |
| 476 | } |
| 477 | |
| 478 | sub warn |
| 479 | { |
| 480 | return __chk(FATAL | MESSAGE, @_); |
| 481 | } |
| 482 | |
| 483 | sub warnif |
| 484 | { |
| 485 | return __chk(NORMAL | FATAL | MESSAGE, @_); |
| 486 | } |
| 487 | |
| 488 | # These are not part of any public interface, so we can delete them to save |
| 489 | # space. |
| 490 | delete @warnings::{qw(NORMAL FATAL MESSAGE)}; |
| 491 | |
| 492 | 1; |
| 493 | __END__ |
| 494 | =head1 NAME |
| 495 | |
| 496 | warnings - Perl pragma to control optional warnings |
| 497 | |
| 498 | =head1 SYNOPSIS |
| 499 | |
| 500 | use warnings; |
| 501 | no warnings; |
| 502 | |
| 503 | use warnings "all"; |
| 504 | no warnings "all"; |
| 505 | |
| 506 | use warnings::register; |
| 507 | if (warnings::enabled()) { |
| 508 | warnings::warn("some warning"); |
| 509 | } |
| 510 | |
| 511 | if (warnings::enabled("void")) { |
| 512 | warnings::warn("void", "some warning"); |
| 513 | } |
| 514 | |
| 515 | if (warnings::enabled($object)) { |
| 516 | warnings::warn($object, "some warning"); |
| 517 | } |
| 518 | |
| 519 | warnings::warnif("some warning"); |
| 520 | warnings::warnif("void", "some warning"); |
| 521 | warnings::warnif($object, "some warning"); |
| 522 | |
| 523 | =head1 DESCRIPTION |
| 524 | |
| 525 | The C<warnings> pragma gives control over which warnings are enabled in |
| 526 | which parts of a Perl program. It's a more flexible alternative for |
| 527 | both the command line flag B<-w> and the equivalent Perl variable, |
| 528 | C<$^W>. |
| 529 | |
| 530 | This pragma works just like the C<strict> pragma. |
| 531 | This means that the scope of the warning pragma is limited to the |
| 532 | enclosing block. It also means that the pragma setting will not |
| 533 | leak across files (via C<use>, C<require> or C<do>). This allows |
| 534 | authors to independently define the degree of warning checks that will |
| 535 | be applied to their module. |
| 536 | |
| 537 | By default, optional warnings are disabled, so any legacy code that |
| 538 | doesn't attempt to control the warnings will work unchanged. |
| 539 | |
| 540 | All warnings are enabled in a block by either of these: |
| 541 | |
| 542 | use warnings; |
| 543 | use warnings 'all'; |
| 544 | |
| 545 | Similarly all warnings are disabled in a block by either of these: |
| 546 | |
| 547 | no warnings; |
| 548 | no warnings 'all'; |
| 549 | |
| 550 | For example, consider the code below: |
| 551 | |
| 552 | use warnings; |
| 553 | my @a; |
| 554 | { |
| 555 | no warnings; |
| 556 | my $b = @a[0]; |
| 557 | } |
| 558 | my $c = @a[0]; |
| 559 | |
| 560 | The code in the enclosing block has warnings enabled, but the inner |
| 561 | block has them disabled. In this case that means the assignment to the |
| 562 | scalar C<$c> will trip the C<"Scalar value @a[0] better written as $a[0]"> |
| 563 | warning, but the assignment to the scalar C<$b> will not. |
| 564 | |
| 565 | =head2 Default Warnings and Optional Warnings |
| 566 | |
| 567 | Before the introduction of lexical warnings, Perl had two classes of |
| 568 | warnings: mandatory and optional. |
| 569 | |
| 570 | As its name suggests, if your code tripped a mandatory warning, you |
| 571 | would get a warning whether you wanted it or not. |
| 572 | For example, the code below would always produce an C<"isn't numeric"> |
| 573 | warning about the "2:". |
| 574 | |
| 575 | my $a = "2:" + 3; |
| 576 | |
| 577 | With the introduction of lexical warnings, mandatory warnings now become |
| 578 | I<default> warnings. The difference is that although the previously |
| 579 | mandatory warnings are still enabled by default, they can then be |
| 580 | subsequently enabled or disabled with the lexical warning pragma. For |
| 581 | example, in the code below, an C<"isn't numeric"> warning will only |
| 582 | be reported for the C<$a> variable. |
| 583 | |
| 584 | my $a = "2:" + 3; |
| 585 | no warnings; |
| 586 | my $b = "2:" + 3; |
| 587 | |
| 588 | Note that neither the B<-w> flag or the C<$^W> can be used to |
| 589 | disable/enable default warnings. They are still mandatory in this case. |
| 590 | |
| 591 | =head2 What's wrong with B<-w> and C<$^W> |
| 592 | |
| 593 | Although very useful, the big problem with using B<-w> on the command |
| 594 | line to enable warnings is that it is all or nothing. Take the typical |
| 595 | scenario when you are writing a Perl program. Parts of the code you |
| 596 | will write yourself, but it's very likely that you will make use of |
| 597 | pre-written Perl modules. If you use the B<-w> flag in this case, you |
| 598 | end up enabling warnings in pieces of code that you haven't written. |
| 599 | |
| 600 | Similarly, using C<$^W> to either disable or enable blocks of code is |
| 601 | fundamentally flawed. For a start, say you want to disable warnings in |
| 602 | a block of code. You might expect this to be enough to do the trick: |
| 603 | |
| 604 | { |
| 605 | local ($^W) = 0; |
| 606 | my $a =+ 2; |
| 607 | my $b; chop $b; |
| 608 | } |
| 609 | |
| 610 | When this code is run with the B<-w> flag, a warning will be produced |
| 611 | for the C<$a> line: C<"Reversed += operator">. |
| 612 | |
| 613 | The problem is that Perl has both compile-time and run-time warnings. To |
| 614 | disable compile-time warnings you need to rewrite the code like this: |
| 615 | |
| 616 | { |
| 617 | BEGIN { $^W = 0 } |
| 618 | my $a =+ 2; |
| 619 | my $b; chop $b; |
| 620 | } |
| 621 | |
| 622 | The other big problem with C<$^W> is the way you can inadvertently |
| 623 | change the warning setting in unexpected places in your code. For example, |
| 624 | when the code below is run (without the B<-w> flag), the second call |
| 625 | to C<doit> will trip a C<"Use of uninitialized value"> warning, whereas |
| 626 | the first will not. |
| 627 | |
| 628 | sub doit |
| 629 | { |
| 630 | my $b; chop $b; |
| 631 | } |
| 632 | |
| 633 | doit(); |
| 634 | |
| 635 | { |
| 636 | local ($^W) = 1; |
| 637 | doit() |
| 638 | } |
| 639 | |
| 640 | This is a side-effect of C<$^W> being dynamically scoped. |
| 641 | |
| 642 | Lexical warnings get around these limitations by allowing finer control |
| 643 | over where warnings can or can't be tripped. |
| 644 | |
| 645 | =head2 Controlling Warnings from the Command Line |
| 646 | |
| 647 | There are three Command Line flags that can be used to control when |
| 648 | warnings are (or aren't) produced: |
| 649 | |
| 650 | =over 5 |
| 651 | |
| 652 | =item B<-w> |
| 653 | X<-w> |
| 654 | |
| 655 | This is the existing flag. If the lexical warnings pragma is B<not> |
| 656 | used in any of you code, or any of the modules that you use, this flag |
| 657 | will enable warnings everywhere. See L<Backward Compatibility> for |
| 658 | details of how this flag interacts with lexical warnings. |
| 659 | |
| 660 | =item B<-W> |
| 661 | X<-W> |
| 662 | |
| 663 | If the B<-W> flag is used on the command line, it will enable all warnings |
| 664 | throughout the program regardless of whether warnings were disabled |
| 665 | locally using C<no warnings> or C<$^W =0>. |
| 666 | This includes all files that get |
| 667 | included via C<use>, C<require> or C<do>. |
| 668 | Think of it as the Perl equivalent of the "lint" command. |
| 669 | |
| 670 | =item B<-X> |
| 671 | X<-X> |
| 672 | |
| 673 | Does the exact opposite to the B<-W> flag, i.e. it disables all warnings. |
| 674 | |
| 675 | =back |
| 676 | |
| 677 | =head2 Backward Compatibility |
| 678 | |
| 679 | If you are used to working with a version of Perl prior to the |
| 680 | introduction of lexically scoped warnings, or have code that uses both |
| 681 | lexical warnings and C<$^W>, this section will describe how they interact. |
| 682 | |
| 683 | How Lexical Warnings interact with B<-w>/C<$^W>: |
| 684 | |
| 685 | =over 5 |
| 686 | |
| 687 | =item 1. |
| 688 | |
| 689 | If none of the three command line flags (B<-w>, B<-W> or B<-X>) that |
| 690 | control warnings is used and neither C<$^W> nor the C<warnings> pragma |
| 691 | are used, then default warnings will be enabled and optional warnings |
| 692 | disabled. |
| 693 | This means that legacy code that doesn't attempt to control the warnings |
| 694 | will work unchanged. |
| 695 | |
| 696 | =item 2. |
| 697 | |
| 698 | The B<-w> flag just sets the global C<$^W> variable as in 5.005. This |
| 699 | means that any legacy code that currently relies on manipulating C<$^W> |
| 700 | to control warning behavior will still work as is. |
| 701 | |
| 702 | =item 3. |
| 703 | |
| 704 | Apart from now being a boolean, the C<$^W> variable operates in exactly |
| 705 | the same horrible uncontrolled global way, except that it cannot |
| 706 | disable/enable default warnings. |
| 707 | |
| 708 | =item 4. |
| 709 | |
| 710 | If a piece of code is under the control of the C<warnings> pragma, |
| 711 | both the C<$^W> variable and the B<-w> flag will be ignored for the |
| 712 | scope of the lexical warning. |
| 713 | |
| 714 | =item 5. |
| 715 | |
| 716 | The only way to override a lexical warnings setting is with the B<-W> |
| 717 | or B<-X> command line flags. |
| 718 | |
| 719 | =back |
| 720 | |
| 721 | The combined effect of 3 & 4 is that it will allow code which uses |
| 722 | the C<warnings> pragma to control the warning behavior of $^W-type |
| 723 | code (using a C<local $^W=0>) if it really wants to, but not vice-versa. |
| 724 | |
| 725 | =head2 Category Hierarchy |
| 726 | X<warning, categories> |
| 727 | |
| 728 | A hierarchy of "categories" have been defined to allow groups of warnings |
| 729 | to be enabled/disabled in isolation. |
| 730 | |
| 731 | The current hierarchy is: |
| 732 | |
| 733 | all -+ |
| 734 | | |
| 735 | +- closure |
| 736 | | |
| 737 | +- deprecated |
| 738 | | |
| 739 | +- exiting |
| 740 | | |
| 741 | +- experimental --+ |
| 742 | | | |
| 743 | | +- experimental::bitwise |
| 744 | | | |
| 745 | | +- experimental::const_attr |
| 746 | | | |
| 747 | | +- experimental::declared_refs |
| 748 | | | |
| 749 | | +- experimental::lexical_subs |
| 750 | | | |
| 751 | | +- experimental::postderef |
| 752 | | | |
| 753 | | +- experimental::re_strict |
| 754 | | | |
| 755 | | +- experimental::refaliasing |
| 756 | | | |
| 757 | | +- experimental::regex_sets |
| 758 | | | |
| 759 | | +- experimental::signatures |
| 760 | | | |
| 761 | | +- experimental::smartmatch |
| 762 | | | |
| 763 | | +- experimental::win32_perlio |
| 764 | | |
| 765 | +- glob |
| 766 | | |
| 767 | +- imprecision |
| 768 | | |
| 769 | +- io ------------+ |
| 770 | | | |
| 771 | | +- closed |
| 772 | | | |
| 773 | | +- exec |
| 774 | | | |
| 775 | | +- layer |
| 776 | | | |
| 777 | | +- newline |
| 778 | | | |
| 779 | | +- pipe |
| 780 | | | |
| 781 | | +- syscalls |
| 782 | | | |
| 783 | | +- unopened |
| 784 | | |
| 785 | +- locale |
| 786 | | |
| 787 | +- misc |
| 788 | | |
| 789 | +- missing |
| 790 | | |
| 791 | +- numeric |
| 792 | | |
| 793 | +- once |
| 794 | | |
| 795 | +- overflow |
| 796 | | |
| 797 | +- pack |
| 798 | | |
| 799 | +- portable |
| 800 | | |
| 801 | +- recursion |
| 802 | | |
| 803 | +- redefine |
| 804 | | |
| 805 | +- redundant |
| 806 | | |
| 807 | +- regexp |
| 808 | | |
| 809 | +- severe --------+ |
| 810 | | | |
| 811 | | +- debugging |
| 812 | | | |
| 813 | | +- inplace |
| 814 | | | |
| 815 | | +- internal |
| 816 | | | |
| 817 | | +- malloc |
| 818 | | |
| 819 | +- shadow |
| 820 | | |
| 821 | +- signal |
| 822 | | |
| 823 | +- substr |
| 824 | | |
| 825 | +- syntax --------+ |
| 826 | | | |
| 827 | | +- ambiguous |
| 828 | | | |
| 829 | | +- bareword |
| 830 | | | |
| 831 | | +- digit |
| 832 | | | |
| 833 | | +- illegalproto |
| 834 | | | |
| 835 | | +- parenthesis |
| 836 | | | |
| 837 | | +- precedence |
| 838 | | | |
| 839 | | +- printf |
| 840 | | | |
| 841 | | +- prototype |
| 842 | | | |
| 843 | | +- qw |
| 844 | | | |
| 845 | | +- reserved |
| 846 | | | |
| 847 | | +- semicolon |
| 848 | | |
| 849 | +- taint |
| 850 | | |
| 851 | +- threads |
| 852 | | |
| 853 | +- uninitialized |
| 854 | | |
| 855 | +- unpack |
| 856 | | |
| 857 | +- untie |
| 858 | | |
| 859 | +- utf8 ----------+ |
| 860 | | | |
| 861 | | +- non_unicode |
| 862 | | | |
| 863 | | +- nonchar |
| 864 | | | |
| 865 | | +- surrogate |
| 866 | | |
| 867 | +- void |
| 868 | |
| 869 | Just like the "strict" pragma any of these categories can be combined |
| 870 | |
| 871 | use warnings qw(void redefine); |
| 872 | no warnings qw(io syntax untie); |
| 873 | |
| 874 | Also like the "strict" pragma, if there is more than one instance of the |
| 875 | C<warnings> pragma in a given scope the cumulative effect is additive. |
| 876 | |
| 877 | use warnings qw(void); # only "void" warnings enabled |
| 878 | ... |
| 879 | use warnings qw(io); # only "void" & "io" warnings enabled |
| 880 | ... |
| 881 | no warnings qw(void); # only "io" warnings enabled |
| 882 | |
| 883 | To determine which category a specific warning has been assigned to see |
| 884 | L<perldiag>. |
| 885 | |
| 886 | Note: Before Perl 5.8.0, the lexical warnings category "deprecated" was a |
| 887 | sub-category of the "syntax" category. It is now a top-level category |
| 888 | in its own right. |
| 889 | |
| 890 | Note: Before 5.21.0, the "missing" lexical warnings category was |
| 891 | internally defined to be the same as the "uninitialized" category. It |
| 892 | is now a top-level category in its own right. |
| 893 | |
| 894 | =head2 Fatal Warnings |
| 895 | X<warning, fatal> |
| 896 | |
| 897 | The presence of the word "FATAL" in the category list will escalate |
| 898 | warnings in those categories into fatal errors in that lexical scope. |
| 899 | |
| 900 | B<NOTE:> FATAL warnings should be used with care, particularly |
| 901 | C<< FATAL => 'all' >>. |
| 902 | |
| 903 | Libraries using L<warnings::warn|/FUNCTIONS> for custom warning categories |
| 904 | generally don't expect L<warnings::warn|/FUNCTIONS> to be fatal and can wind up |
| 905 | in an unexpected state as a result. For XS modules issuing categorized |
| 906 | warnings, such unanticipated exceptions could also expose memory leak bugs. |
| 907 | |
| 908 | Moreover, the Perl interpreter itself has had serious bugs involving |
| 909 | fatalized warnings. For a summary of resolved and unresolved problems as |
| 910 | of January 2015, please see |
| 911 | L<this perl5-porters post|http://www.nntp.perl.org/group/perl.perl5.porters/2015/01/msg225235.html>. |
| 912 | |
| 913 | While some developers find fatalizing some warnings to be a useful |
| 914 | defensive programming technique, using C<< FATAL => 'all' >> to fatalize |
| 915 | all possible warning categories -- including custom ones -- is particularly |
| 916 | risky. Therefore, the use of C<< FATAL => 'all' >> is |
| 917 | L<discouraged|perlpolicy/discouraged>. |
| 918 | |
| 919 | The L<strictures|strictures/VERSION-2> module on CPAN offers one example of |
| 920 | a warnings subset that the module's authors believe is relatively safe to |
| 921 | fatalize. |
| 922 | |
| 923 | B<NOTE:> users of FATAL warnings, especially those using |
| 924 | C<< FATAL => 'all' >>, should be fully aware that they are risking future |
| 925 | portability of their programs by doing so. Perl makes absolutely no |
| 926 | commitments to not introduce new warnings or warnings categories in the |
| 927 | future; indeed, we explicitly reserve the right to do so. Code that may |
| 928 | not warn now may warn in a future release of Perl if the Perl5 development |
| 929 | team deems it in the best interests of the community to do so. Should code |
| 930 | using FATAL warnings break due to the introduction of a new warning we will |
| 931 | NOT consider it an incompatible change. Users of FATAL warnings should |
| 932 | take special caution during upgrades to check to see if their code triggers |
| 933 | any new warnings and should pay particular attention to the fine print of |
| 934 | the documentation of the features they use to ensure they do not exploit |
| 935 | features that are documented as risky, deprecated, or unspecified, or where |
| 936 | the documentation says "so don't do that", or anything with the same sense |
| 937 | and spirit. Use of such features in combination with FATAL warnings is |
| 938 | ENTIRELY AT THE USER'S RISK. |
| 939 | |
| 940 | The following documentation describes how to use FATAL warnings but the |
| 941 | perl5 porters strongly recommend that you understand the risks before doing |
| 942 | so, especially for library code intended for use by others, as there is no |
| 943 | way for downstream users to change the choice of fatal categories. |
| 944 | |
| 945 | In the code below, the use of C<time>, C<length> |
| 946 | and C<join> can all produce a C<"Useless use of xxx in void context"> |
| 947 | warning. |
| 948 | |
| 949 | use warnings; |
| 950 | |
| 951 | time; |
| 952 | |
| 953 | { |
| 954 | use warnings FATAL => qw(void); |
| 955 | length "abc"; |
| 956 | } |
| 957 | |
| 958 | join "", 1,2,3; |
| 959 | |
| 960 | print "done\n"; |
| 961 | |
| 962 | When run it produces this output |
| 963 | |
| 964 | Useless use of time in void context at fatal line 3. |
| 965 | Useless use of length in void context at fatal line 7. |
| 966 | |
| 967 | The scope where C<length> is used has escalated the C<void> warnings |
| 968 | category into a fatal error, so the program terminates immediately when it |
| 969 | encounters the warning. |
| 970 | |
| 971 | To explicitly turn off a "FATAL" warning you just disable the warning |
| 972 | it is associated with. So, for example, to disable the "void" warning |
| 973 | in the example above, either of these will do the trick: |
| 974 | |
| 975 | no warnings qw(void); |
| 976 | no warnings FATAL => qw(void); |
| 977 | |
| 978 | If you want to downgrade a warning that has been escalated into a fatal |
| 979 | error back to a normal warning, you can use the "NONFATAL" keyword. For |
| 980 | example, the code below will promote all warnings into fatal errors, |
| 981 | except for those in the "syntax" category. |
| 982 | |
| 983 | use warnings FATAL => 'all', NONFATAL => 'syntax'; |
| 984 | |
| 985 | As of Perl 5.20, instead of C<< use warnings FATAL => 'all'; >> you can |
| 986 | use: |
| 987 | |
| 988 | use v5.20; # Perl 5.20 or greater is required for the following |
| 989 | use warnings 'FATAL'; # short form of "use warnings FATAL => 'all';" |
| 990 | |
| 991 | If you want your program to be compatible with versions of Perl before |
| 992 | 5.20, you must use C<< use warnings FATAL => 'all'; >> instead. (In |
| 993 | previous versions of Perl, the behavior of the statements |
| 994 | C<< use warnings 'FATAL'; >>, C<< use warnings 'NONFATAL'; >> and |
| 995 | C<< no warnings 'FATAL'; >> was unspecified; they did not behave as if |
| 996 | they included the C<< => 'all' >> portion. As of 5.20, they do.) |
| 997 | |
| 998 | =head2 Reporting Warnings from a Module |
| 999 | X<warning, reporting> X<warning, registering> |
| 1000 | |
| 1001 | The C<warnings> pragma provides a number of functions that are useful for |
| 1002 | module authors. These are used when you want to report a module-specific |
| 1003 | warning to a calling module has enabled warnings via the C<warnings> |
| 1004 | pragma. |
| 1005 | |
| 1006 | Consider the module C<MyMod::Abc> below. |
| 1007 | |
| 1008 | package MyMod::Abc; |
| 1009 | |
| 1010 | use warnings::register; |
| 1011 | |
| 1012 | sub open { |
| 1013 | my $path = shift; |
| 1014 | if ($path !~ m#^/#) { |
| 1015 | warnings::warn("changing relative path to /var/abc") |
| 1016 | if warnings::enabled(); |
| 1017 | $path = "/var/abc/$path"; |
| 1018 | } |
| 1019 | } |
| 1020 | |
| 1021 | 1; |
| 1022 | |
| 1023 | The call to C<warnings::register> will create a new warnings category |
| 1024 | called "MyMod::Abc", i.e. the new category name matches the current |
| 1025 | package name. The C<open> function in the module will display a warning |
| 1026 | message if it gets given a relative path as a parameter. This warnings |
| 1027 | will only be displayed if the code that uses C<MyMod::Abc> has actually |
| 1028 | enabled them with the C<warnings> pragma like below. |
| 1029 | |
| 1030 | use MyMod::Abc; |
| 1031 | use warnings 'MyMod::Abc'; |
| 1032 | ... |
| 1033 | abc::open("../fred.txt"); |
| 1034 | |
| 1035 | It is also possible to test whether the pre-defined warnings categories are |
| 1036 | set in the calling module with the C<warnings::enabled> function. Consider |
| 1037 | this snippet of code: |
| 1038 | |
| 1039 | package MyMod::Abc; |
| 1040 | |
| 1041 | sub open { |
| 1042 | if (warnings::enabled("deprecated")) { |
| 1043 | warnings::warn("deprecated", |
| 1044 | "open is deprecated, use new instead"); |
| 1045 | } |
| 1046 | new(@_); |
| 1047 | } |
| 1048 | |
| 1049 | sub new |
| 1050 | ... |
| 1051 | 1; |
| 1052 | |
| 1053 | The function C<open> has been deprecated, so code has been included to |
| 1054 | display a warning message whenever the calling module has (at least) the |
| 1055 | "deprecated" warnings category enabled. Something like this, say. |
| 1056 | |
| 1057 | use warnings 'deprecated'; |
| 1058 | use MyMod::Abc; |
| 1059 | ... |
| 1060 | MyMod::Abc::open($filename); |
| 1061 | |
| 1062 | Either the C<warnings::warn> or C<warnings::warnif> function should be |
| 1063 | used to actually display the warnings message. This is because they can |
| 1064 | make use of the feature that allows warnings to be escalated into fatal |
| 1065 | errors. So in this case |
| 1066 | |
| 1067 | use MyMod::Abc; |
| 1068 | use warnings FATAL => 'MyMod::Abc'; |
| 1069 | ... |
| 1070 | MyMod::Abc::open('../fred.txt'); |
| 1071 | |
| 1072 | the C<warnings::warnif> function will detect this and die after |
| 1073 | displaying the warning message. |
| 1074 | |
| 1075 | The three warnings functions, C<warnings::warn>, C<warnings::warnif> |
| 1076 | and C<warnings::enabled> can optionally take an object reference in place |
| 1077 | of a category name. In this case the functions will use the class name |
| 1078 | of the object as the warnings category. |
| 1079 | |
| 1080 | Consider this example: |
| 1081 | |
| 1082 | package Original; |
| 1083 | |
| 1084 | no warnings; |
| 1085 | use warnings::register; |
| 1086 | |
| 1087 | sub new |
| 1088 | { |
| 1089 | my $class = shift; |
| 1090 | bless [], $class; |
| 1091 | } |
| 1092 | |
| 1093 | sub check |
| 1094 | { |
| 1095 | my $self = shift; |
| 1096 | my $value = shift; |
| 1097 | |
| 1098 | if ($value % 2 && warnings::enabled($self)) |
| 1099 | { warnings::warn($self, "Odd numbers are unsafe") } |
| 1100 | } |
| 1101 | |
| 1102 | sub doit |
| 1103 | { |
| 1104 | my $self = shift; |
| 1105 | my $value = shift; |
| 1106 | $self->check($value); |
| 1107 | # ... |
| 1108 | } |
| 1109 | |
| 1110 | 1; |
| 1111 | |
| 1112 | package Derived; |
| 1113 | |
| 1114 | use warnings::register; |
| 1115 | use Original; |
| 1116 | our @ISA = qw( Original ); |
| 1117 | sub new |
| 1118 | { |
| 1119 | my $class = shift; |
| 1120 | bless [], $class; |
| 1121 | } |
| 1122 | |
| 1123 | |
| 1124 | 1; |
| 1125 | |
| 1126 | The code below makes use of both modules, but it only enables warnings from |
| 1127 | C<Derived>. |
| 1128 | |
| 1129 | use Original; |
| 1130 | use Derived; |
| 1131 | use warnings 'Derived'; |
| 1132 | my $a = Original->new(); |
| 1133 | $a->doit(1); |
| 1134 | my $b = Derived->new(); |
| 1135 | $a->doit(1); |
| 1136 | |
| 1137 | When this code is run only the C<Derived> object, C<$b>, will generate |
| 1138 | a warning. |
| 1139 | |
| 1140 | Odd numbers are unsafe at main.pl line 7 |
| 1141 | |
| 1142 | Notice also that the warning is reported at the line where the object is first |
| 1143 | used. |
| 1144 | |
| 1145 | When registering new categories of warning, you can supply more names to |
| 1146 | warnings::register like this: |
| 1147 | |
| 1148 | package MyModule; |
| 1149 | use warnings::register qw(format precision); |
| 1150 | |
| 1151 | ... |
| 1152 | |
| 1153 | warnings::warnif('MyModule::format', '...'); |
| 1154 | |
| 1155 | =head1 FUNCTIONS |
| 1156 | |
| 1157 | =over 4 |
| 1158 | |
| 1159 | =item use warnings::register |
| 1160 | |
| 1161 | Creates a new warnings category with the same name as the package where |
| 1162 | the call to the pragma is used. |
| 1163 | |
| 1164 | =item warnings::enabled() |
| 1165 | |
| 1166 | Use the warnings category with the same name as the current package. |
| 1167 | |
| 1168 | Return TRUE if that warnings category is enabled in the calling module. |
| 1169 | Otherwise returns FALSE. |
| 1170 | |
| 1171 | =item warnings::enabled($category) |
| 1172 | |
| 1173 | Return TRUE if the warnings category, C<$category>, is enabled in the |
| 1174 | calling module. |
| 1175 | Otherwise returns FALSE. |
| 1176 | |
| 1177 | =item warnings::enabled($object) |
| 1178 | |
| 1179 | Use the name of the class for the object reference, C<$object>, as the |
| 1180 | warnings category. |
| 1181 | |
| 1182 | Return TRUE if that warnings category is enabled in the first scope |
| 1183 | where the object is used. |
| 1184 | Otherwise returns FALSE. |
| 1185 | |
| 1186 | =item warnings::fatal_enabled() |
| 1187 | |
| 1188 | Return TRUE if the warnings category with the same name as the current |
| 1189 | package has been set to FATAL in the calling module. |
| 1190 | Otherwise returns FALSE. |
| 1191 | |
| 1192 | =item warnings::fatal_enabled($category) |
| 1193 | |
| 1194 | Return TRUE if the warnings category C<$category> has been set to FATAL in |
| 1195 | the calling module. |
| 1196 | Otherwise returns FALSE. |
| 1197 | |
| 1198 | =item warnings::fatal_enabled($object) |
| 1199 | |
| 1200 | Use the name of the class for the object reference, C<$object>, as the |
| 1201 | warnings category. |
| 1202 | |
| 1203 | Return TRUE if that warnings category has been set to FATAL in the first |
| 1204 | scope where the object is used. |
| 1205 | Otherwise returns FALSE. |
| 1206 | |
| 1207 | =item warnings::warn($message) |
| 1208 | |
| 1209 | Print C<$message> to STDERR. |
| 1210 | |
| 1211 | Use the warnings category with the same name as the current package. |
| 1212 | |
| 1213 | If that warnings category has been set to "FATAL" in the calling module |
| 1214 | then die. Otherwise return. |
| 1215 | |
| 1216 | =item warnings::warn($category, $message) |
| 1217 | |
| 1218 | Print C<$message> to STDERR. |
| 1219 | |
| 1220 | If the warnings category, C<$category>, has been set to "FATAL" in the |
| 1221 | calling module then die. Otherwise return. |
| 1222 | |
| 1223 | =item warnings::warn($object, $message) |
| 1224 | |
| 1225 | Print C<$message> to STDERR. |
| 1226 | |
| 1227 | Use the name of the class for the object reference, C<$object>, as the |
| 1228 | warnings category. |
| 1229 | |
| 1230 | If that warnings category has been set to "FATAL" in the scope where C<$object> |
| 1231 | is first used then die. Otherwise return. |
| 1232 | |
| 1233 | |
| 1234 | =item warnings::warnif($message) |
| 1235 | |
| 1236 | Equivalent to: |
| 1237 | |
| 1238 | if (warnings::enabled()) |
| 1239 | { warnings::warn($message) } |
| 1240 | |
| 1241 | =item warnings::warnif($category, $message) |
| 1242 | |
| 1243 | Equivalent to: |
| 1244 | |
| 1245 | if (warnings::enabled($category)) |
| 1246 | { warnings::warn($category, $message) } |
| 1247 | |
| 1248 | =item warnings::warnif($object, $message) |
| 1249 | |
| 1250 | Equivalent to: |
| 1251 | |
| 1252 | if (warnings::enabled($object)) |
| 1253 | { warnings::warn($object, $message) } |
| 1254 | |
| 1255 | =item warnings::register_categories(@names) |
| 1256 | |
| 1257 | This registers warning categories for the given names and is primarily for |
| 1258 | use by the warnings::register pragma. |
| 1259 | |
| 1260 | =back |
| 1261 | |
| 1262 | See also L<perlmodlib/Pragmatic Modules> and L<perldiag>. |
| 1263 | |
| 1264 | =cut |
| 1265 | |
| 1266 | # ex: set ro: |