1<html> 2<head> 3<title>pcre2build specification</title> 4</head> 5<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB"> 6<h1>pcre2build man page</h1> 7<p> 8Return to the <a href="index.html">PCRE2 index page</a>. 9</p> 10<p> 11This page is part of the PCRE2 HTML documentation. It was generated 12automatically from the original man page. If there is any nonsense in it, 13please consult the man page, in case the conversion went wrong. 14<br> 15<ul> 16<li><a name="TOC1" href="#SEC1">BUILDING PCRE2</a> 17<li><a name="TOC2" href="#SEC2">PCRE2 BUILD-TIME OPTIONS</a> 18<li><a name="TOC3" href="#SEC3">BUILDING 8-BIT, 16-BIT AND 32-BIT LIBRARIES</a> 19<li><a name="TOC4" href="#SEC4">BUILDING SHARED AND STATIC LIBRARIES</a> 20<li><a name="TOC5" href="#SEC5">UNICODE AND UTF SUPPORT</a> 21<li><a name="TOC6" href="#SEC6">DISABLING THE USE OF \C</a> 22<li><a name="TOC7" href="#SEC7">JUST-IN-TIME COMPILER SUPPORT</a> 23<li><a name="TOC8" href="#SEC8">NEWLINE RECOGNITION</a> 24<li><a name="TOC9" href="#SEC9">WHAT \R MATCHES</a> 25<li><a name="TOC10" href="#SEC10">HANDLING VERY LARGE PATTERNS</a> 26<li><a name="TOC11" href="#SEC11">LIMITING PCRE2 RESOURCE USAGE</a> 27<li><a name="TOC12" href="#SEC12">CREATING CHARACTER TABLES AT BUILD TIME</a> 28<li><a name="TOC13" href="#SEC13">USING EBCDIC CODE</a> 29<li><a name="TOC14" href="#SEC14">PCRE2GREP SUPPORT FOR EXTERNAL SCRIPTS</a> 30<li><a name="TOC15" href="#SEC15">PCRE2GREP OPTIONS FOR COMPRESSED FILE SUPPORT</a> 31<li><a name="TOC16" href="#SEC16">PCRE2GREP BUFFER SIZE</a> 32<li><a name="TOC17" href="#SEC17">PCRE2TEST OPTION FOR LIBREADLINE SUPPORT</a> 33<li><a name="TOC18" href="#SEC18">INCLUDING DEBUGGING CODE</a> 34<li><a name="TOC19" href="#SEC19">DEBUGGING WITH VALGRIND SUPPORT</a> 35<li><a name="TOC20" href="#SEC20">CODE COVERAGE REPORTING</a> 36<li><a name="TOC21" href="#SEC21">DISABLING THE Z AND T FORMATTING MODIFIERS</a> 37<li><a name="TOC22" href="#SEC22">SUPPORT FOR FUZZERS</a> 38<li><a name="TOC23" href="#SEC23">OBSOLETE OPTION</a> 39<li><a name="TOC24" href="#SEC24">SEE ALSO</a> 40<li><a name="TOC25" href="#SEC25">AUTHOR</a> 41<li><a name="TOC26" href="#SEC26">REVISION</a> 42</ul> 43<br><a name="SEC1" href="#TOC1">BUILDING PCRE2</a><br> 44<P> 45PCRE2 is distributed with a <b>configure</b> script that can be used to build 46the library in Unix-like environments using the applications known as 47Autotools. Also in the distribution are files to support building using 48<b>CMake</b> instead of <b>configure</b>. The text file 49<a href="README.txt"><b>README</b></a> 50contains general information about building with Autotools (some of which is 51repeated below), and also has some comments about building on various operating 52systems. There is a lot more information about building PCRE2 without using 53Autotools (including information about using <b>CMake</b> and building "by 54hand") in the text file called 55<a href="NON-AUTOTOOLS-BUILD.txt"><b>NON-AUTOTOOLS-BUILD</b>.</a> 56You should consult this file as well as the 57<a href="README.txt"><b>README</b></a> 58file if you are building in a non-Unix-like environment. 59</P> 60<br><a name="SEC2" href="#TOC1">PCRE2 BUILD-TIME OPTIONS</a><br> 61<P> 62The rest of this document describes the optional features of PCRE2 that can be 63selected when the library is compiled. It assumes use of the <b>configure</b> 64script, where the optional features are selected or deselected by providing 65options to <b>configure</b> before running the <b>make</b> command. However, the 66same options can be selected in both Unix-like and non-Unix-like environments 67if you are using <b>CMake</b> instead of <b>configure</b> to build PCRE2. 68</P> 69<P> 70If you are not using Autotools or <b>CMake</b>, option selection can be done by 71editing the <b>config.h</b> file, or by passing parameter settings to the 72compiler, as described in 73<a href="NON-AUTOTOOLS-BUILD.txt"><b>NON-AUTOTOOLS-BUILD</b>.</a> 74</P> 75<P> 76The complete list of options for <b>configure</b> (which includes the standard 77ones such as the selection of the installation directory) can be obtained by 78running 79<pre> 80 ./configure --help 81</pre> 82The following sections include descriptions of "on/off" options whose names 83begin with --enable or --disable. Because of the way that <b>configure</b> 84works, --enable and --disable always come in pairs, so the complementary option 85always exists as well, but as it specifies the default, it is not described. 86Options that specify values have names that start with --with. At the end of a 87<b>configure</b> run, a summary of the configuration is output. 88</P> 89<br><a name="SEC3" href="#TOC1">BUILDING 8-BIT, 16-BIT AND 32-BIT LIBRARIES</a><br> 90<P> 91By default, a library called <b>libpcre2-8</b> is built, containing functions 92that take string arguments contained in arrays of bytes, interpreted either as 93single-byte characters, or UTF-8 strings. You can also build two other 94libraries, called <b>libpcre2-16</b> and <b>libpcre2-32</b>, which process 95strings that are contained in arrays of 16-bit and 32-bit code units, 96respectively. These can be interpreted either as single-unit characters or 97UTF-16/UTF-32 strings. To build these additional libraries, add one or both of 98the following to the <b>configure</b> command: 99<pre> 100 --enable-pcre2-16 101 --enable-pcre2-32 102</pre> 103If you do not want the 8-bit library, add 104<pre> 105 --disable-pcre2-8 106</pre> 107as well. At least one of the three libraries must be built. Note that the POSIX 108wrapper is for the 8-bit library only, and that <b>pcre2grep</b> is an 8-bit 109program. Neither of these are built if you select only the 16-bit or 32-bit 110libraries. 111</P> 112<br><a name="SEC4" href="#TOC1">BUILDING SHARED AND STATIC LIBRARIES</a><br> 113<P> 114The Autotools PCRE2 building process uses <b>libtool</b> to build both shared 115and static libraries by default. You can suppress an unwanted library by adding 116one of 117<pre> 118 --disable-shared 119 --disable-static 120</pre> 121to the <b>configure</b> command. 122</P> 123<br><a name="SEC5" href="#TOC1">UNICODE AND UTF SUPPORT</a><br> 124<P> 125By default, PCRE2 is built with support for Unicode and UTF character strings. 126To build it without Unicode support, add 127<pre> 128 --disable-unicode 129</pre> 130to the <b>configure</b> command. This setting applies to all three libraries. It 131is not possible to build one library with Unicode support and another without 132in the same configuration. 133</P> 134<P> 135Of itself, Unicode support does not make PCRE2 treat strings as UTF-8, UTF-16 136or UTF-32. To do that, applications that use the library can set the PCRE2_UTF 137option when they call <b>pcre2_compile()</b> to compile a pattern. 138Alternatively, patterns may be started with (*UTF) unless the application has 139locked this out by setting PCRE2_NEVER_UTF. 140</P> 141<P> 142UTF support allows the libraries to process character code points up to 1430x10ffff in the strings that they handle. Unicode support also gives access to 144the Unicode properties of characters, using pattern escapes such as \P, \p, 145and \X. Only the general category properties such as <i>Lu</i> and <i>Nd</i>, 146script names, and some bi-directional properties are supported. Details are 147given in the 148<a href="pcre2pattern.html"><b>pcre2pattern</b></a> 149documentation. 150</P> 151<P> 152Pattern escapes such as \d and \w do not by default make use of Unicode 153properties. The application can request that they do by setting the PCRE2_UCP 154option. Unless the application has set PCRE2_NEVER_UCP, a pattern may also 155request this by starting with (*UCP). 156</P> 157<br><a name="SEC6" href="#TOC1">DISABLING THE USE OF \C</a><br> 158<P> 159The \C escape sequence, which matches a single code unit, even in a UTF mode, 160can cause unpredictable behaviour because it may leave the current matching 161point in the middle of a multi-code-unit character. The application can lock it 162out by setting the PCRE2_NEVER_BACKSLASH_C option when calling 163<b>pcre2_compile()</b>. There is also a build-time option 164<pre> 165 --enable-never-backslash-C 166</pre> 167(note the upper case C) which locks out the use of \C entirely. 168</P> 169<br><a name="SEC7" href="#TOC1">JUST-IN-TIME COMPILER SUPPORT</a><br> 170<P> 171Just-in-time (JIT) compiler support is included in the build by specifying 172<pre> 173 --enable-jit 174</pre> 175This support is available only for certain hardware architectures. If this 176option is set for an unsupported architecture, a building error occurs. 177If in doubt, use 178<pre> 179 --enable-jit=auto 180</pre> 181which enables JIT only if the current hardware is supported. You can check 182if JIT is enabled in the configuration summary that is output at the end of a 183<b>configure</b> run. If you are enabling JIT under SELinux you may also want to 184add 185<pre> 186 --enable-jit-sealloc 187</pre> 188which enables the use of an execmem allocator in JIT that is compatible with 189SELinux. This has no effect if JIT is not enabled. See the 190<a href="pcre2jit.html"><b>pcre2jit</b></a> 191documentation for a discussion of JIT usage. When JIT support is enabled, 192<b>pcre2grep</b> automatically makes use of it, unless you add 193<pre> 194 --disable-pcre2grep-jit 195</pre> 196to the <b>configure</b> command. 197</P> 198<br><a name="SEC8" href="#TOC1">NEWLINE RECOGNITION</a><br> 199<P> 200By default, PCRE2 interprets the linefeed (LF) character as indicating the end 201of a line. This is the normal newline character on Unix-like systems. You can 202compile PCRE2 to use carriage return (CR) instead, by adding 203<pre> 204 --enable-newline-is-cr 205</pre> 206to the <b>configure</b> command. There is also an --enable-newline-is-lf option, 207which explicitly specifies linefeed as the newline character. 208</P> 209<P> 210Alternatively, you can specify that line endings are to be indicated by the 211two-character sequence CRLF (CR immediately followed by LF). If you want this, 212add 213<pre> 214 --enable-newline-is-crlf 215</pre> 216to the <b>configure</b> command. There is a fourth option, specified by 217<pre> 218 --enable-newline-is-anycrlf 219</pre> 220which causes PCRE2 to recognize any of the three sequences CR, LF, or CRLF as 221indicating a line ending. A fifth option, specified by 222<pre> 223 --enable-newline-is-any 224</pre> 225causes PCRE2 to recognize any Unicode newline sequence. The Unicode newline 226sequences are the three just mentioned, plus the single characters VT (vertical 227tab, U+000B), FF (form feed, U+000C), NEL (next line, U+0085), LS (line 228separator, U+2028), and PS (paragraph separator, U+2029). The final option is 229<pre> 230 --enable-newline-is-nul 231</pre> 232which causes NUL (binary zero) to be set as the default line-ending character. 233</P> 234<P> 235Whatever default line ending convention is selected when PCRE2 is built can be 236overridden by applications that use the library. At build time it is 237recommended to use the standard for your operating system. 238</P> 239<br><a name="SEC9" href="#TOC1">WHAT \R MATCHES</a><br> 240<P> 241By default, the sequence \R in a pattern matches any Unicode newline sequence, 242independently of what has been selected as the line ending sequence. If you 243specify 244<pre> 245 --enable-bsr-anycrlf 246</pre> 247the default is changed so that \R matches only CR, LF, or CRLF. Whatever is 248selected when PCRE2 is built can be overridden by applications that use the 249library. 250</P> 251<br><a name="SEC10" href="#TOC1">HANDLING VERY LARGE PATTERNS</a><br> 252<P> 253Within a compiled pattern, offset values are used to point from one part to 254another (for example, from an opening parenthesis to an alternation 255metacharacter). By default, in the 8-bit and 16-bit libraries, two-byte values 256are used for these offsets, leading to a maximum size for a compiled pattern of 257around 64 thousand code units. This is sufficient to handle all but the most 258gigantic patterns. Nevertheless, some people do want to process truly enormous 259patterns, so it is possible to compile PCRE2 to use three-byte or four-byte 260offsets by adding a setting such as 261<pre> 262 --with-link-size=3 263</pre> 264to the <b>configure</b> command. The value given must be 2, 3, or 4. For the 26516-bit library, a value of 3 is rounded up to 4. In these libraries, using 266longer offsets slows down the operation of PCRE2 because it has to load 267additional data when handling them. For the 32-bit library the value is always 2684 and cannot be overridden; the value of --with-link-size is ignored. 269</P> 270<br><a name="SEC11" href="#TOC1">LIMITING PCRE2 RESOURCE USAGE</a><br> 271<P> 272The <b>pcre2_match()</b> function increments a counter each time it goes round 273its main loop. Putting a limit on this counter controls the amount of computing 274resource used by a single call to <b>pcre2_match()</b>. The limit can be changed 275at run time, as described in the 276<a href="pcre2api.html"><b>pcre2api</b></a> 277documentation. The default is 10 million, but this can be changed by adding a 278setting such as 279<pre> 280 --with-match-limit=500000 281</pre> 282to the <b>configure</b> command. This setting also applies to the 283<b>pcre2_dfa_match()</b> matching function, and to JIT matching (though the 284counting is done differently). 285</P> 286<P> 287The <b>pcre2_match()</b> function starts out using a 20KiB vector on the system 288stack to record backtracking points. The more nested backtracking points there 289are (that is, the deeper the search tree), the more memory is needed. If the 290initial vector is not large enough, heap memory is used, up to a certain limit, 291which is specified in kibibytes (units of 1024 bytes). The limit can be changed 292at run time, as described in the 293<a href="pcre2api.html"><b>pcre2api</b></a> 294documentation. The default limit (in effect unlimited) is 20 million. You can 295change this by a setting such as 296<pre> 297 --with-heap-limit=500 298</pre> 299which limits the amount of heap to 500 KiB. This limit applies only to 300interpretive matching in <b>pcre2_match()</b> and <b>pcre2_dfa_match()</b>, which 301may also use the heap for internal workspace when processing complicated 302patterns. This limit does not apply when JIT (which has its own memory 303arrangements) is used. 304</P> 305<P> 306You can also explicitly limit the depth of nested backtracking in the 307<b>pcre2_match()</b> interpreter. This limit defaults to the value that is set 308for --with-match-limit. You can set a lower default limit by adding, for 309example, 310<pre> 311 --with-match-limit-depth=10000 312</pre> 313to the <b>configure</b> command. This value can be overridden at run time. This 314depth limit indirectly limits the amount of heap memory that is used, but 315because the size of each backtracking "frame" depends on the number of 316capturing parentheses in a pattern, the amount of heap that is used before the 317limit is reached varies from pattern to pattern. This limit was more useful in 318versions before 10.30, where function recursion was used for backtracking. 319</P> 320<P> 321As well as applying to <b>pcre2_match()</b>, the depth limit also controls 322the depth of recursive function calls in <b>pcre2_dfa_match()</b>. These are 323used for lookaround assertions, atomic groups, and recursion within patterns. 324The limit does not apply to JIT matching. 325<a name="createtables"></a></P> 326<br><a name="SEC12" href="#TOC1">CREATING CHARACTER TABLES AT BUILD TIME</a><br> 327<P> 328PCRE2 uses fixed tables for processing characters whose code points are less 329than 256. By default, PCRE2 is built with a set of tables that are distributed 330in the file <i>src/pcre2_chartables.c.dist</i>. These tables are for ASCII codes 331only. If you add 332<pre> 333 --enable-rebuild-chartables 334</pre> 335to the <b>configure</b> command, the distributed tables are no longer used. 336Instead, a program called <b>pcre2_dftables</b> is compiled and run. This 337outputs the source for new set of tables, created in the default locale of your 338C run-time system. This method of replacing the tables does not work if you are 339cross compiling, because <b>pcre2_dftables</b> needs to be run on the local 340host and therefore not compiled with the cross compiler. 341</P> 342<P> 343If you need to create alternative tables when cross compiling, you will have to 344do so "by hand". There may also be other reasons for creating tables manually. 345To cause <b>pcre2_dftables</b> to be built on the local host, run a normal 346compiling command, and then run the program with the output file as its 347argument, for example: 348<pre> 349 cc src/pcre2_dftables.c -o pcre2_dftables 350 ./pcre2_dftables src/pcre2_chartables.c 351</pre> 352This builds the tables in the default locale of the local host. If you want to 353specify a locale, you must use the -L option: 354<pre> 355 LC_ALL=fr_FR ./pcre2_dftables -L src/pcre2_chartables.c 356</pre> 357You can also specify -b (with or without -L). This causes the tables to be 358written in binary instead of as source code. A set of binary tables can be 359loaded into memory by an application and passed to <b>pcre2_compile()</b> in the 360same way as tables created by calling <b>pcre2_maketables()</b>. The tables are 361just a string of bytes, independent of hardware characteristics such as 362endianness. This means they can be bundled with an application that runs in 363different environments, to ensure consistent behaviour. 364</P> 365<br><a name="SEC13" href="#TOC1">USING EBCDIC CODE</a><br> 366<P> 367PCRE2 assumes by default that it will run in an environment where the character 368code is ASCII or Unicode, which is a superset of ASCII. This is the case for 369most computer operating systems. PCRE2 can, however, be compiled to run in an 3708-bit EBCDIC environment by adding 371<pre> 372 --enable-ebcdic --disable-unicode 373</pre> 374to the <b>configure</b> command. This setting implies 375--enable-rebuild-chartables. You should only use it if you know that you are in 376an EBCDIC environment (for example, an IBM mainframe operating system). 377</P> 378<P> 379It is not possible to support both EBCDIC and UTF-8 codes in the same version 380of the library. Consequently, --enable-unicode and --enable-ebcdic are mutually 381exclusive. 382</P> 383<P> 384The EBCDIC character that corresponds to an ASCII LF is assumed to have the 385value 0x15 by default. However, in some EBCDIC environments, 0x25 is used. In 386such an environment you should use 387<pre> 388 --enable-ebcdic-nl25 389</pre> 390as well as, or instead of, --enable-ebcdic. The EBCDIC character for CR has the 391same value as in ASCII, namely, 0x0d. Whichever of 0x15 and 0x25 is <i>not</i> 392chosen as LF is made to correspond to the Unicode NEL character (which, in 393Unicode, is 0x85). 394</P> 395<P> 396The options that select newline behaviour, such as --enable-newline-is-cr, 397and equivalent run-time options, refer to these character values in an EBCDIC 398environment. 399</P> 400<br><a name="SEC14" href="#TOC1">PCRE2GREP SUPPORT FOR EXTERNAL SCRIPTS</a><br> 401<P> 402By default <b>pcre2grep</b> supports the use of callouts with string arguments 403within the patterns it is matching. There are two kinds: one that generates 404output using local code, and another that calls an external program or script. 405If --disable-pcre2grep-callout-fork is added to the <b>configure</b> command, 406only the first kind of callout is supported; if --disable-pcre2grep-callout is 407used, all callouts are completely ignored. For more details of <b>pcre2grep</b> 408callouts, see the 409<a href="pcre2grep.html"><b>pcre2grep</b></a> 410documentation. 411</P> 412<br><a name="SEC15" href="#TOC1">PCRE2GREP OPTIONS FOR COMPRESSED FILE SUPPORT</a><br> 413<P> 414By default, <b>pcre2grep</b> reads all files as plain text. You can build it so 415that it recognizes files whose names end in <b>.gz</b> or <b>.bz2</b>, and reads 416them with <b>libz</b> or <b>libbz2</b>, respectively, by adding one or both of 417<pre> 418 --enable-pcre2grep-libz 419 --enable-pcre2grep-libbz2 420</pre> 421to the <b>configure</b> command. These options naturally require that the 422relevant libraries are installed on your system. Configuration will fail if 423they are not. 424</P> 425<br><a name="SEC16" href="#TOC1">PCRE2GREP BUFFER SIZE</a><br> 426<P> 427<b>pcre2grep</b> uses an internal buffer to hold a "window" on the file it is 428scanning, in order to be able to output "before" and "after" lines when it 429finds a match. The default starting size of the buffer is 20KiB. The buffer 430itself is three times this size, but because of the way it is used for holding 431"before" lines, the longest line that is guaranteed to be processable is the 432notional buffer size. If a longer line is encountered, <b>pcre2grep</b> 433automatically expands the buffer, up to a specified maximum size, whose default 434is 1MiB or the starting size, whichever is the larger. You can change the 435default parameter values by adding, for example, 436<pre> 437 --with-pcre2grep-bufsize=51200 438 --with-pcre2grep-max-bufsize=2097152 439</pre> 440to the <b>configure</b> command. The caller of <b>pcre2grep</b> can override 441these values by using --buffer-size and --max-buffer-size on the command line. 442</P> 443<br><a name="SEC17" href="#TOC1">PCRE2TEST OPTION FOR LIBREADLINE SUPPORT</a><br> 444<P> 445If you add one of 446<pre> 447 --enable-pcre2test-libreadline 448 --enable-pcre2test-libedit 449</pre> 450to the <b>configure</b> command, <b>pcre2test</b> is linked with the 451<b>libreadline</b> or<b>libedit</b> library, respectively, and when its input is 452from a terminal, it reads it using the <b>readline()</b> function. This provides 453line-editing and history facilities. Note that <b>libreadline</b> is 454GPL-licensed, so if you distribute a binary of <b>pcre2test</b> linked in this 455way, there may be licensing issues. These can be avoided by linking instead 456with <b>libedit</b>, which has a BSD licence. 457</P> 458<P> 459Setting --enable-pcre2test-libreadline causes the <b>-lreadline</b> option to be 460added to the <b>pcre2test</b> build. In many operating environments with a 461sytem-installed readline library this is sufficient. However, in some 462environments (e.g. if an unmodified distribution version of readline is in 463use), some extra configuration may be necessary. The INSTALL file for 464<b>libreadline</b> says this: 465<pre> 466 "Readline uses the termcap functions, but does not link with 467 the termcap or curses library itself, allowing applications 468 which link with readline the to choose an appropriate library." 469</pre> 470If your environment has not been set up so that an appropriate library is 471automatically included, you may need to add something like 472<pre> 473 LIBS="-ncurses" 474</pre> 475immediately before the <b>configure</b> command. 476</P> 477<br><a name="SEC18" href="#TOC1">INCLUDING DEBUGGING CODE</a><br> 478<P> 479If you add 480<pre> 481 --enable-debug 482</pre> 483to the <b>configure</b> command, additional debugging code is included in the 484build. This feature is intended for use by the PCRE2 maintainers. 485</P> 486<br><a name="SEC19" href="#TOC1">DEBUGGING WITH VALGRIND SUPPORT</a><br> 487<P> 488If you add 489<pre> 490 --enable-valgrind 491</pre> 492to the <b>configure</b> command, PCRE2 will use valgrind annotations to mark 493certain memory regions as unaddressable. This allows it to detect invalid 494memory accesses, and is mostly useful for debugging PCRE2 itself. 495</P> 496<br><a name="SEC20" href="#TOC1">CODE COVERAGE REPORTING</a><br> 497<P> 498If your C compiler is gcc, you can build a version of PCRE2 that can generate a 499code coverage report for its test suite. To enable this, you must install 500<b>lcov</b> version 1.6 or above. Then specify 501<pre> 502 --enable-coverage 503</pre> 504to the <b>configure</b> command and build PCRE2 in the usual way. 505</P> 506<P> 507Note that using <b>ccache</b> (a caching C compiler) is incompatible with code 508coverage reporting. If you have configured <b>ccache</b> to run automatically 509on your system, you must set the environment variable 510<pre> 511 CCACHE_DISABLE=1 512</pre> 513before running <b>make</b> to build PCRE2, so that <b>ccache</b> is not used. 514</P> 515<P> 516When --enable-coverage is used, the following addition targets are added to the 517<i>Makefile</i>: 518<pre> 519 make coverage 520</pre> 521This creates a fresh coverage report for the PCRE2 test suite. It is equivalent 522to running "make coverage-reset", "make coverage-baseline", "make check", and 523then "make coverage-report". 524<pre> 525 make coverage-reset 526</pre> 527This zeroes the coverage counters, but does nothing else. 528<pre> 529 make coverage-baseline 530</pre> 531This captures baseline coverage information. 532<pre> 533 make coverage-report 534</pre> 535This creates the coverage report. 536<pre> 537 make coverage-clean-report 538</pre> 539This removes the generated coverage report without cleaning the coverage data 540itself. 541<pre> 542 make coverage-clean-data 543</pre> 544This removes the captured coverage data without removing the coverage files 545created at compile time (*.gcno). 546<pre> 547 make coverage-clean 548</pre> 549This cleans all coverage data including the generated coverage report. For more 550information about code coverage, see the <b>gcov</b> and <b>lcov</b> 551documentation. 552</P> 553<br><a name="SEC21" href="#TOC1">DISABLING THE Z AND T FORMATTING MODIFIERS</a><br> 554<P> 555The C99 standard defines formatting modifiers z and t for size_t and 556ptrdiff_t values, respectively. By default, PCRE2 uses these modifiers in 557environments other than old versions of Microsoft Visual Studio when 558__STDC_VERSION__ is defined and has a value greater than or equal to 199901L 559(indicating support for C99). 560However, there is at least one environment that claims to be C99 but does not 561support these modifiers. If 562<pre> 563 --disable-percent-zt 564</pre> 565is specified, no use is made of the z or t modifiers. Instead of %td or %zu, 566a suitable format is used depending in the size of long for the platform. 567</P> 568<br><a name="SEC22" href="#TOC1">SUPPORT FOR FUZZERS</a><br> 569<P> 570There is a special option for use by people who want to run fuzzing tests on 571PCRE2: 572<pre> 573 --enable-fuzz-support 574</pre> 575At present this applies only to the 8-bit library. If set, it causes an extra 576library called libpcre2-fuzzsupport.a to be built, but not installed. This 577contains a single function called LLVMFuzzerTestOneInput() whose arguments are 578a pointer to a string and the length of the string. When called, this function 579tries to compile the string as a pattern, and if that succeeds, to match it. 580This is done both with no options and with some random options bits that are 581generated from the string. 582</P> 583<P> 584Setting --enable-fuzz-support also causes a binary called <b>pcre2fuzzcheck</b> 585to be created. This is normally run under valgrind or used when PCRE2 is 586compiled with address sanitizing enabled. It calls the fuzzing function and 587outputs information about what it is doing. The input strings are specified by 588arguments: if an argument starts with "=" the rest of it is a literal input 589string. Otherwise, it is assumed to be a file name, and the contents of the 590file are the test string. 591</P> 592<br><a name="SEC23" href="#TOC1">OBSOLETE OPTION</a><br> 593<P> 594In versions of PCRE2 prior to 10.30, there were two ways of handling 595backtracking in the <b>pcre2_match()</b> function. The default was to use the 596system stack, but if 597<pre> 598 --disable-stack-for-recursion 599</pre> 600was set, memory on the heap was used. From release 10.30 onwards this has 601changed (the stack is no longer used) and this option now does nothing except 602give a warning. 603</P> 604<br><a name="SEC24" href="#TOC1">SEE ALSO</a><br> 605<P> 606<b>pcre2api</b>(3), <b>pcre2-config</b>(3). 607</P> 608<br><a name="SEC25" href="#TOC1">AUTHOR</a><br> 609<P> 610Philip Hazel 611<br> 612University Computing Service 613<br> 614Cambridge, England. 615<br> 616</P> 617<br><a name="SEC26" href="#TOC1">REVISION</a><br> 618<P> 619Last updated: 08 December 2021 620<br> 621Copyright © 1997-2021 University of Cambridge. 622<br> 623<p> 624Return to the <a href="index.html">PCRE2 index page</a>. 625</p> 626