Config.in 66 KB

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  1. #
  2. # For a description of the syntax of this configuration file,
  3. # see extra/config/Kconfig-language.txt
  4. #
  5. mainmenu "uClibc C Library Configuration"
  6. choice
  7. prompt "Target Architecture"
  8. help
  9. The architecture of your target.
  10. config TARGET_alpha
  11. bool "alpha"
  12. config TARGET_arm
  13. bool "arm"
  14. config TARGET_avr32
  15. bool "avr32"
  16. config TARGET_bfin
  17. bool "bfin"
  18. config TARGET_cris
  19. bool "cris"
  20. config TARGET_e1
  21. bool "e1 (BROKEN)"
  22. config TARGET_frv
  23. bool "frv (BROKEN)"
  24. config TARGET_h8300
  25. bool "h8300 (BROKEN)"
  26. config TARGET_hppa
  27. bool "hppa"
  28. config TARGET_i386
  29. bool "i386"
  30. config TARGET_i960
  31. bool "i960 (BROKEN)"
  32. config TARGET_ia64
  33. bool "ia64"
  34. config TARGET_m68k
  35. bool "m68k"
  36. config TARGET_microblaze
  37. bool "microblaze (BROKEN)"
  38. config TARGET_mips
  39. bool "mips"
  40. config TARGET_nios
  41. bool "nios"
  42. config TARGET_nios2
  43. bool "nios2"
  44. config TARGET_powerpc
  45. bool "powerpc"
  46. config TARGET_sh
  47. bool "superh"
  48. config TARGET_sh64
  49. bool "sh64"
  50. config TARGET_sparc
  51. bool "sparc"
  52. config TARGET_v850
  53. bool "v850 (BROKEN)"
  54. config TARGET_vax
  55. bool "vax"
  56. config TARGET_x86_64
  57. bool "x86_64"
  58. config TARGET_xtensa
  59. bool "xtensa"
  60. endchoice
  61. menu "Target Architecture Features and Options"
  62. if TARGET_alpha
  63. source "extra/Configs/Config.alpha"
  64. endif
  65. if TARGET_arm
  66. source "extra/Configs/Config.arm"
  67. endif
  68. if TARGET_avr32
  69. source "extra/Configs/Config.avr32"
  70. endif
  71. if TARGET_bfin
  72. source "extra/Configs/Config.bfin"
  73. endif
  74. if TARGET_cris
  75. source "extra/Configs/Config.cris"
  76. endif
  77. if TARGET_e1
  78. source "extra/Configs/Config.e1"
  79. endif
  80. if TARGET_frv
  81. source "extra/Configs/Config.frv"
  82. endif
  83. if TARGET_h8300
  84. source "extra/Configs/Config.h8300"
  85. endif
  86. if TARGET_hppa
  87. source "extra/Configs/Config.hppa"
  88. endif
  89. if TARGET_i386
  90. source "extra/Configs/Config.i386"
  91. endif
  92. if TARGET_i960
  93. source "extra/Configs/Config.i960"
  94. endif
  95. if TARGET_ia64
  96. source "extra/Configs/Config.ia64"
  97. endif
  98. if TARGET_m68k
  99. source "extra/Configs/Config.m68k"
  100. endif
  101. if TARGET_nios
  102. source "extra/Configs/Config.nios"
  103. endif
  104. if TARGET_nios2
  105. source "extra/Configs/Config.nios2"
  106. endif
  107. if TARGET_microblaze
  108. source "extra/Configs/Config.microblaze"
  109. endif
  110. if TARGET_mips
  111. source "extra/Configs/Config.mips"
  112. endif
  113. if TARGET_powerpc
  114. source "extra/Configs/Config.powerpc"
  115. endif
  116. if TARGET_sh
  117. source "extra/Configs/Config.sh"
  118. endif
  119. if TARGET_sh64
  120. source "extra/Configs/Config.sh64"
  121. endif
  122. if TARGET_sparc
  123. source "extra/Configs/Config.sparc"
  124. endif
  125. if TARGET_v850
  126. source "extra/Configs/Config.v850"
  127. endif
  128. if TARGET_vax
  129. source "extra/Configs/Config.vax"
  130. endif
  131. if TARGET_x86_64
  132. source "extra/Configs/Config.x86_64"
  133. endif
  134. if TARGET_xtensa
  135. source "extra/Configs/Config.xtensa"
  136. endif
  137. config TARGET_SUBARCH
  138. string
  139. default "e500" if CONFIG_E500
  140. default "classic" if CONFIG_CLASSIC
  141. default "sh4" if CONFIG_SH4
  142. default ""
  143. source "extra/Configs/Config.in.arch"
  144. endmenu
  145. menu "General Library Settings"
  146. config HAVE_NO_PIC
  147. bool
  148. default n
  149. config DOPIC
  150. bool "Generate only Position Independent Code (PIC)"
  151. default y
  152. depends on !HAVE_NO_PIC
  153. help
  154. If you wish to build all of uClibc as PIC objects, then answer Y here.
  155. If you are unsure, then you should answer N.
  156. config ARCH_HAS_NO_SHARED
  157. bool
  158. default n
  159. config ARCH_HAS_NO_LDSO
  160. bool
  161. select ARCH_HAS_NO_SHARED
  162. default n
  163. config HAVE_SHARED
  164. bool "Enable support for shared libraries"
  165. depends on !ARCH_HAS_NO_SHARED
  166. default y
  167. help
  168. If you wish to build uClibc with support for shared libraries then
  169. answer Y here. If you only want to build uClibc as a static library,
  170. then answer N.
  171. config FORCE_SHAREABLE_TEXT_SEGMENTS
  172. bool "Only load shared libraries which can share their text segment"
  173. depends on HAVE_SHARED
  174. default n
  175. help
  176. If you answer Y here, the uClibc native shared library loader will
  177. only load shared libraries, which do not need to modify any
  178. non-writable segments. These libraries haven't set the DT_TEXTREL
  179. tag in the dynamic section (==> objdump).
  180. All your libraries must be compiled with -fPIC or -fpic, and all
  181. assembler function must be written as position independent code (PIC).
  182. Enabling this option will make uClibc's shared library loader a
  183. little bit smaller and guarantee that no memory will be wasted by
  184. badly coded shared libraries.
  185. config LDSO_LDD_SUPPORT
  186. bool "Native 'ldd' support"
  187. depends on HAVE_SHARED
  188. default y
  189. help
  190. Enable this to enable all the code needed to support traditional ldd,
  191. which executes the shared library loader to resolve all dependencies
  192. and then provide a list of shared libraries that are required for an
  193. application to function. Disabling this option will makes uClibc's
  194. shared library loader a little bit smaller.
  195. Most people will answer Y.
  196. config LDSO_CACHE_SUPPORT
  197. bool "Enable library loader cache (ld.so.conf)"
  198. depends on HAVE_SHARED
  199. default y
  200. help
  201. Enable this to make use of /etc/ld.so.conf, the shared library loader
  202. cache configuration file to support for non-standard library paths.
  203. After updating this file, it is necessary to run 'ldconfig' to update
  204. the /etc/ld.so.cache shared library loader cache file.
  205. config LDSO_PRELOAD_FILE_SUPPORT
  206. bool "Enable library loader preload file (ld.so.preload)"
  207. depends on HAVE_SHARED
  208. default n
  209. help
  210. Enable this to make use of /etc/ld.so.preload. This file contains a
  211. whitespace separated list of shared libraries to be loaded before
  212. the program.
  213. config LDSO_BASE_FILENAME
  214. string "Shared library loader naming prefix"
  215. depends on HAVE_SHARED && (LDSO_CACHE_SUPPORT || LDSO_PRELOAD_FILE_SUPPORT)
  216. default "ld.so"
  217. help
  218. If you wish to support both uClibc and glibc on the same system, it
  219. is necessary to set this to something other than "ld.so" to avoid
  220. conflicts with glibc, which also uses "ld.so". This prevents both
  221. libraries from using the same /etc/ld.so.* files. If you wish to
  222. support both uClibc and glibc on the same system then you should set
  223. this to "ld-uClibc.so".
  224. Most people will leave this set to the default of "ld.so".
  225. WARNING: Changing the default prefix could cause problems with
  226. binutils' ld !
  227. config UCLIBC_STATIC_LDCONFIG
  228. bool "Link ldconfig statically"
  229. depends on HAVE_SHARED
  230. default y
  231. help
  232. Enable this option to statically link the ldconfig binary.
  233. Making ldconfig static can be beneficial if you have a library
  234. problem and need to use ldconfig to recover. Sometimes, it is
  235. preferable to instead keep the size of the system down, in which
  236. case you should disable this option.
  237. config LDSO_RUNPATH
  238. bool "Enable ELF RUNPATH tag support"
  239. depends on HAVE_SHARED
  240. default y
  241. help
  242. ELF's may have dynamic RPATH/RUNPATH tags. These tags list paths
  243. which extend the library search paths. They are really only useful
  244. if a package installs libraries in non standard locations and
  245. ld.so.conf support is disabled.
  246. Usage of RUNPATH tags is not too common, so disabling this feature
  247. should be safe for most people.
  248. config UCLIBC_CTOR_DTOR
  249. bool "Support global constructors and destructors"
  250. default y
  251. help
  252. If you wish to build uClibc with support for global constructor
  253. (ctor) and global destructor (dtor) support, then answer Y here.
  254. When ctor/dtor support is enabled, binaries linked with uClibc must
  255. also be linked with crtbegin.o and crtend.o which are provided by gcc
  256. (the "*startfile:" and "*endfile:" settings in your gcc specs file
  257. may need to be adjusted to include these files). This support will
  258. also add a small amount of additional size to each binary compiled vs
  259. uClibc. If you will be using uClibc with C++, or if you need the gcc
  260. __attribute__((constructor)) and __attribute__((destructor)) to work,
  261. then you definitely want to answer Y here. If you don't need ctors
  262. or dtors and want your binaries to be as small as possible, then
  263. answer N.
  264. config LDSO_GNU_HASH_SUPPORT
  265. bool "Enable GNU hash style support"
  266. depends on HAVE_SHARED
  267. default n
  268. help
  269. Newest binutils support a new hash style named GNU-hash. The dynamic
  270. linker will use the new GNU-hash section (.gnu.hash) for symbol lookup
  271. if present into the ELF binaries, otherwise it will use the old SysV
  272. hash style (.hash). This ensures that it is completely backward
  273. compatible.
  274. Further, being the hash table implementation self-contained into each
  275. executable and shared libraries, objects with mixed hash style can
  276. peacefully coexist in the same process.
  277. If you want to use this new feature, answer Y
  278. config HAS_NO_THREADS
  279. bool
  280. default n
  281. config UCLIBC_HAS_THREADS
  282. bool "POSIX Threading support"
  283. depends on !HAS_NO_THREADS
  284. default y
  285. # linuxthreads and linuxthreads.old need nanosleep()
  286. select UCLIBC_HAS_REALTIME
  287. help
  288. If you want to compile uClibc with pthread support, then answer Y.
  289. This will increase the size of uClibc by adding a bunch of locking
  290. to critical data structures, and adding extra code to ensure that
  291. functions are properly reentrant.
  292. If your applications require pthreads, answer Y.
  293. config UCLIBC_HAS_TLS
  294. bool "Thread-Local Storage"
  295. depends on UCLIBC_HAS_THREADS && !LINUXTHREADS_OLD
  296. default n
  297. help
  298. If you want to enable TLS support then answer Y.
  299. This is fast an efficient way to store per-thread local data
  300. which is not on stack. It needs __thread support enabled in
  301. gcc.
  302. config PTHREADS_DEBUG_SUPPORT
  303. bool "Build pthreads debugging support"
  304. default n
  305. depends on UCLIBC_HAS_THREADS
  306. help
  307. Say Y here if you wish to be able to debug applications that use
  308. uClibc's pthreads library. By enabling this option, a library
  309. named libthread_db will be built. This library will be dlopen()'d
  310. by gdb and will allow gdb to debug the threads in your application.
  311. IMPORTANT NOTE! Because gdb must dlopen() the libthread_db library,
  312. you must compile gdb with uClibc in order for pthread debugging to
  313. work properly.
  314. If you are doing development and want to debug applications using
  315. uClibc's pthread library, answer Y. Otherwise, answer N.
  316. config LINUXTHREADS_OLD
  317. bool "Use the older (stable) version of linuxthreads"
  318. default y
  319. depends on UCLIBC_HAS_THREADS && !UCLIBC_HAS_THREADS_NATIVE
  320. help
  321. There are two versions of linuxthreads. The older (stable) version
  322. has been in uClibc for quite a long time but hasn't seen too many
  323. updates other than bugfixes.
  324. The new version has not been tested much, and lacks ports for arches
  325. which glibc does not support (like bfin/frv/etc...), but is based on
  326. the latest code from glibc, so it may be the only choice for the
  327. newer ports (like alpha/amd64/64bit arches and hppa).
  328. config UCLIBC_HAS_THREADS_NATIVE
  329. bool "Native POSIX Threading (NPTL) Support"
  330. depends on UCLIBC_HAS_THREADS
  331. default n
  332. select UCLIBC_HAS_TLS
  333. help
  334. If you want to compile uClibc with NPTL support, then answer Y.
  335. IMPORTANT NOTE! NPTL requires a Linux 2.6 kernel, binutils
  336. at least version 2.16 and GCC with at least version 4.1.0. NPTL
  337. will not work with older versions of any above sources. If you
  338. ignore any of these guidelines, you do so at your own risk. Do
  339. not ask for help on any of the development mailing lists.
  340. !!!! WARNING !!!! BIG FAT WARNING !!!! REALLY BIG FAT WARNING !!!!
  341. This is experimental code and at times it may not even build and
  342. even if it does it might decide to do random damage. This code is
  343. potentially hazardous to your health and sanity. It will remain
  344. that way until further notice at which point this notice will
  345. disappear. Thank you for your support and for not smoking.
  346. config LINUXTHREADS_NEW
  347. def_bool y
  348. depends on UCLIBC_HAS_THREADS && !LINUXTHREADS_OLD && !UCLIBC_HAS_THREADS_NATIVE
  349. config UCLIBC_HAS_SYSLOG
  350. bool "Syslog support"
  351. default y
  352. depends on UCLIBC_HAS_NETWORK_SUPPORT
  353. select UCLIBC_HAS_SOCKET
  354. help
  355. Support sending messages to the system logger.
  356. This requires socket-support.
  357. config UCLIBC_HAS_LFS
  358. bool "Large File Support"
  359. default y
  360. help
  361. If you wish to build uClibc with support for accessing large files
  362. (i.e. files greater then 2 GiB) then answer Y. Do not enable this
  363. if you are using an older Linux kernel (2.0.x) that lacks large file
  364. support. Enabling this option will increase the size of uClibc.
  365. choice
  366. prompt "Malloc Implementation"
  367. default MALLOC if ! ARCH_USE_MMU
  368. default MALLOC_STANDARD if ARCH_USE_MMU
  369. config MALLOC
  370. bool "malloc"
  371. help
  372. "malloc" use mmap for all allocations and so works very well on
  373. MMU-less systems that do not support the brk() system call. It is
  374. pretty smart about reusing already allocated memory, and minimizing
  375. memory wastage.
  376. This is the default for uClinux MMU-less systems.
  377. config MALLOC_SIMPLE
  378. bool "malloc-simple"
  379. help
  380. "malloc-simple" is trivially simple and slow as molasses. It
  381. was written from scratch for uClibc, and is the simplest possible
  382. (and therefore smallest) malloc implementation.
  383. This uses only the mmap() system call to allocate and free memory,
  384. and does not use the brk() system call at all, making it a fine
  385. choice for MMU-less systems with very limited memory. It's 100%
  386. standards compliant, thread safe, very small, and releases freed
  387. memory back to the OS immediately rather than keeping it in the
  388. process's heap for reallocation. It is also VERY SLOW.
  389. config MALLOC_STANDARD
  390. bool "malloc-standard"
  391. depends on ARCH_USE_MMU
  392. help
  393. "malloc-standard" is derived from the public domain dlmalloc
  394. implementation by Doug Lea. It is quite fast, and is pretty smart
  395. about reusing already allocated memory, and minimizing memory
  396. wastage. This uses brk() for small allocations, while using mmap()
  397. for larger allocations. This is the default malloc implementation
  398. for uClibc.
  399. If unsure, answer "malloc-standard".
  400. endchoice
  401. config MALLOC_GLIBC_COMPAT
  402. bool "Malloc returns live pointer for malloc(0)"
  403. default n
  404. help
  405. The behavior of malloc(0) is listed as implementation-defined by
  406. SuSv3. Glibc returns a valid pointer to something, while uClibc
  407. normally returns NULL. I personally feel glibc's behavior is
  408. not particularly safe, and allows buggy applications to hide very
  409. serious problems.
  410. When this option is enabled, uClibc will act just like glibc, and
  411. return a live pointer when someone calls malloc(0). This pointer
  412. provides a malloc'ed area with a size of 1 byte. This feature is
  413. mostly useful when dealing with applications using autoconf's broken
  414. AC_FUNC_MALLOC macro (which redefines malloc as rpl_malloc if it
  415. does not detect glibc style returning-a-valid-pointer-for-malloc(0)
  416. behavior). Most people can safely answer N.
  417. config UCLIBC_DYNAMIC_ATEXIT
  418. bool "Dynamic atexit() Support"
  419. default y
  420. help
  421. When this option is enabled, uClibc will support an infinite number,
  422. of atexit() and on_exit() functions, limited only by your available
  423. memory. This can be important when uClibc is used with C++, since
  424. global destructors are implemented via atexit(), and it is quite
  425. possible to exceed the default number when this option is disabled.
  426. Enabling this option adds a few bytes, and more significantly makes
  427. atexit and on_exit depend on malloc, which can be bad when compiling
  428. static executables.
  429. Unless you use uClibc with C++, you should probably answer N.
  430. config COMPAT_ATEXIT
  431. bool "Old (visible) atexit Support"
  432. default n
  433. help
  434. Enable this option if you want to update from 0.9.28 to svn/0.9.29,
  435. else you will be missing atexit() until you rebuild all apps.
  436. config UCLIBC_SUSV3_LEGACY
  437. bool "Enable SuSv3 LEGACY functions"
  438. default n
  439. #vfork,
  440. # h_errno
  441. # gethostbyaddr
  442. # gethostbyname
  443. help
  444. Enable this option if you want to have SuSv3 LEGACY functions
  445. in the library, else they are replaced by SuSv3 proposed macros.
  446. Currently applies to:
  447. bcmp, bcopy, bzero, index, rindex, ftime,
  448. bsd_signal, (ecvt), (fcvt), gcvt, (getcontext),
  449. (getwd), (makecontext),
  450. mktemp, (pthread_attr_getstackaddr), (pthread_attr_setstackaddr),
  451. scalb, (setcontext), (swapcontext), ualarm, usleep,
  452. wcswcs.
  453. WARNING! ABI incompatibility.
  454. config UCLIBC_SUSV3_LEGACY_MACROS
  455. bool "Enable SuSv3 LEGACY macros"
  456. default n
  457. help
  458. Enable this option if you want to have SuSv3 LEGACY macros.
  459. Currently applies to bcopy/bzero/bcmp/index/rindex et al.
  460. WARNING! ABI incompatibility.
  461. config UCLIBC_SUSV4_LEGACY
  462. bool "Enable SuSv4 LEGACY or obsolescent functions"
  463. default n
  464. help
  465. Enable this option if you want to have SuSv4 LEGACY functions
  466. and macros in the library.
  467. Currently applies to:
  468. - XSI functions:
  469. _longjmp, _setjmp, _tolower, _toupper, ftw, getitimer,
  470. gettimeofday, isascii, pthread_getconcurrency,
  471. pthread_setconcurrency, setitimer, setpgrp, sighold,
  472. sigignore, sigpause, sigrelse, sigset, siginterrupt,
  473. tempnam, toascii, ulimit.
  474. - Base functions:
  475. asctime, asctime_r, ctime, ctime_r, gets, rand_r,
  476. tmpnam, utime.
  477. WARNING! ABI incompatibility.
  478. config UCLIBC_HAS_STUBS
  479. bool "Provide stubs for unavailable functionality"
  480. default n
  481. help
  482. With this option uClibc provides non-functional stubs for
  483. functions which are impossible to implement on the target
  484. architecture. Otherwise, such functions are simply omitted.
  485. As of 2008-07, this option makes uClibc provide fork() stub
  486. on NOMMU targets. It always sets errno to ENOSYS and returns -1.
  487. This may be useful if you port a lot of software and cannot
  488. audit all of it and replace or disable fork() usage.
  489. With this option, a program which uses fork() will build
  490. successfully. Of course, it may be useless if fork()
  491. is essential for its operation.
  492. config UCLIBC_HAS_SHADOW
  493. bool "Shadow Password Support"
  494. default y
  495. help
  496. Answer N if you do not need shadow password support.
  497. Most people will answer Y.
  498. config UCLIBC_HAS_PROGRAM_INVOCATION_NAME
  499. bool "Support for program_invocation_name"
  500. default n
  501. help
  502. Support for the GNU-specific program_invocation_name and
  503. program_invocation_short_name strings. Some GNU packages
  504. (like tar and coreutils) utilize these for extra useful
  505. output, but in general are not required.
  506. At startup, these external strings are automatically set
  507. up based on the value of ARGV[0].
  508. If unsure, just answer N.
  509. config UCLIBC_HAS___PROGNAME
  510. bool "Support for __progname"
  511. default y
  512. depends on UCLIBC_HAS_PROGRAM_INVOCATION_NAME
  513. help
  514. Some packages (like openssh) like to peek into internal libc
  515. symbols to make their output a bit more user friendly.
  516. At startup, __progname is automatically set up based on the
  517. value of ARGV[0].
  518. If unsure, just answer N.
  519. config UCLIBC_HAS_PTY
  520. bool "Support for pseudo-terminals"
  521. default y
  522. help
  523. This enables support for pseudo-terminals (see man 4 pts
  524. and man 7 pty).
  525. If unsure, just answer Y.
  526. config ASSUME_DEVPTS
  527. bool "Assume that /dev/pts is a devpts or devfs file system"
  528. default y
  529. depends on UCLIBC_HAS_PTY
  530. help
  531. Enable this if /dev/pts is on a devpts or devfs filesystem. Both
  532. these filesystems automatically manage permissions on the /dev/pts
  533. devices. You may need to mount your devpts or devfs filesystem on
  534. /dev/pts for this to work.
  535. Most people should answer Y.
  536. config UNIX98PTY_ONLY
  537. bool "Support only Unix 98 PTYs"
  538. default y
  539. depends on UCLIBC_HAS_PTY
  540. help
  541. If you want to support only Unix 98 PTYs enable this. Some older
  542. applications may need this disabled and will thus use legacy BSD
  543. style PTY handling which is more complex and also bigger than
  544. Unix 98 PTY handling.
  545. For most current programs, you can generally answer Y.
  546. if UNIX98PTY_ONLY
  547. config UCLIBC_HAS_GETPT
  548. bool "Support getpt() (glibc-compat)"
  549. default n
  550. depends on UCLIBC_HAS_PTY
  551. help
  552. Some packages may need getpt().
  553. All of those are non-standard and can be considered
  554. GNU/libc compatibility.
  555. Either use posix_openpt() or just open /dev/ptmx yourself.
  556. If unsure, just say N.
  557. endif
  558. if !UNIX98PTY_ONLY
  559. # Have to use __libc_ptyname{1,2}[] and related bloat
  560. config UCLIBC_HAS_GETPT
  561. def_bool y
  562. endif
  563. config UCLIBC_HAS_TM_EXTENSIONS
  564. bool "Support 'struct tm' timezone extension fields"
  565. default y
  566. help
  567. Enabling this option adds fields to 'struct tm' in time.h for
  568. tracking the number of seconds east of UTC, and an abbreviation for
  569. the current timezone. These fields are not specified by the SuSv3
  570. standard, but they are commonly used in both GNU and BSD application
  571. code.
  572. To strictly follow the SuSv3 standard, leave this disabled.
  573. Most people will probably want to answer Y.
  574. config UCLIBC_HAS_TZ_CACHING
  575. bool "Enable caching of the last valid timezone 'TZ' string"
  576. default y
  577. help
  578. Answer Y to enable caching of the last valid 'TZ' string describing
  579. the timezone setting. This allows a quick string compare to avoid
  580. repeated parsing of unchanged 'TZ' strings when tzset() is called.
  581. Most people will answer Y.
  582. config UCLIBC_HAS_TZ_FILE
  583. bool "Enable '/etc/TZ' file support to set a default timezone (uClibc-specific)"
  584. default y
  585. help
  586. Answer Y to enable the setting of a default timezone for uClibc.
  587. Ordinarily, uClibc gets the timezone information exclusively from the
  588. 'TZ' environment variable. In particular, there is no support for
  589. the zoneinfo directory tree or the /etc/timezone file used by glibc.
  590. With this option enabled, uClibc will use the value stored in the
  591. file '/etc/TZ' (default path) to obtain timezone information if the
  592. 'TZ' environment variable is missing or has an invalid value. The
  593. file consists of a single line (newline required) of text describing
  594. the timezone in the format specified for the TZ environment variable.
  595. Doing 'echo CST6CDT > /etc/TZ' is enough to create a valid file.
  596. See
  597. http://www.opengroup.org/onlinepubs/007904975/basedefs/xbd_chap08.html
  598. for details on valid settings of 'TZ'.
  599. Most people will answer Y.
  600. config UCLIBC_HAS_TZ_FILE_READ_MANY
  601. bool "Repeatedly read the '/etc/TZ' file"
  602. depends on UCLIBC_HAS_TZ_FILE
  603. default y
  604. help
  605. Answer Y to enable repeated reading of the '/etc/TZ' file even after
  606. a valid value has been read. This incurs the overhead of an
  607. open/read/close for each tzset() call (explicit or implied). However,
  608. setting this will allow applications to update their timezone
  609. information if the contents of the file change.
  610. Most people will answer Y.
  611. config UCLIBC_TZ_FILE_PATH
  612. string "Path to the 'TZ' file for setting the global timezone"
  613. depends on UCLIBC_HAS_TZ_FILE
  614. default "/etc/TZ"
  615. help
  616. This is the path to the 'TZ' file.
  617. Most people will use the default of '/etc/TZ'.
  618. endmenu
  619. menu "Advanced Library Settings"
  620. config UCLIBC_PWD_BUFFER_SIZE
  621. int "Buffer size for getpwnam() and friends"
  622. default 256
  623. range 12 1024
  624. help
  625. This sets the value of the buffer size for getpwnam() and friends.
  626. By default, this is 256. (For reference, glibc uses 1024).
  627. The value can be found using sysconf() with the _SC_GETPW_R_SIZE_MAX
  628. parameter.
  629. config UCLIBC_GRP_BUFFER_SIZE
  630. int "Buffer size for getgrnam() and friends"
  631. default 256
  632. range 12 1024
  633. help
  634. This sets the value of the buffer size for getgrnam() and friends.
  635. By default, this is 256. (For reference, glibc uses 1024).
  636. The value can be found using sysconf() with the _SC_GETGR_R_SIZE_MAX
  637. parameter.
  638. comment "Support various families of functions"
  639. config UCLIBC_LINUX_MODULE_24
  640. bool "Linux kernel module functions"
  641. default !(TARGET_bfin)
  642. help
  643. create_module, query_module
  644. are used in linux (prior to 2.6) for loadable kernel modules.
  645. Say N if you do not use kernel modules, or you only support
  646. Linux 2.6+.
  647. config UCLIBC_LINUX_SPECIFIC
  648. bool "Linux specific functions"
  649. default y
  650. help
  651. capget(), capset(), fstatfs(), inotify_*(), ioperm(), iopl(),
  652. madvise(), modify_ldt(), personality(), prctl()/arch_prctl(),
  653. ppoll(), readahead(), reboot(), remap_file_pages(),
  654. sched_getaffinity(), sched_setaffinity(), sendfile(),
  655. setfsgid(), setfsuid(), setresuid(),
  656. splice(), vmsplice(), tee(), signalfd(), swapoff(), swapon(),
  657. sync_file_range(), sysctl(), sysinfo(), vhangup()
  658. config UCLIBC_HAS_GNU_ERROR
  659. bool "Support GNU extensions for error-reporting"
  660. default y
  661. help
  662. Support for the GNU-specific error(), error_at_line(),
  663. void (* error_print_progname)(), error_message_count
  664. functions and variables. Some GNU packages
  665. utilize these for extra useful output, but in general
  666. are not required.
  667. If unsure, just answer N.
  668. config UCLIBC_BSD_SPECIFIC
  669. bool "BSD specific functions"
  670. default y
  671. help
  672. mincore(), getdomainname(), setdomainname()
  673. If unsure, say N.
  674. config UCLIBC_HAS_BSD_ERR
  675. bool "BSD err functions"
  676. default y
  677. help
  678. These functions are non-standard BSD extensions.
  679. err(), errx(), warn(), warnx(), verr(), verrx(), vwarn(), vwarnx()
  680. If unsure, say N.
  681. config UCLIBC_HAS_OBSOLETE_BSD_SIGNAL
  682. bool "BSD obsolete signal functions"
  683. default n
  684. help
  685. These functions are provided as a compatibility interface for
  686. programs that make use of the historical System V signal API.
  687. This API is obsolete:
  688. new applications should use the POSIX signal API (sigaction(2),
  689. sigprocmask(2), etc.).
  690. Affected functions:
  691. sigset(), sighold(), sigrelse(), sigignore()
  692. If unsure, say N.
  693. config UCLIBC_HAS_OBSOLETE_SYSV_SIGNAL
  694. bool "SYSV obsolete signal functions"
  695. default n
  696. help
  697. Use of sysv_signal() should be avoided; use sigaction(2) instead.
  698. If unsure, say N.
  699. config UCLIBC_NTP_LEGACY
  700. bool "ntp_*() aliases"
  701. default n
  702. help
  703. Provide legacy aliases for ntp functions:
  704. ntp_adjtime(), ntp_gettime()
  705. It is safe to say N here.
  706. config UCLIBC_SV4_DEPRECATED
  707. bool "Enable SVr4 deprecated functions"
  708. default n
  709. help
  710. These functions are DEPRECATED in System V release 4.
  711. Say N unless you desparately need one of the functions below:
  712. ustat() [use statfs(2) in your code instead]
  713. config UCLIBC_HAS_REALTIME
  714. bool "Realtime-related family of SUSv functions"
  715. default y
  716. help
  717. These functions are part of the Timers option and need not
  718. be available on all implementations.
  719. Includes AIO, message-queue, scheduler, semaphore functions:
  720. aio.h
  721. mqueue.h
  722. sched.h
  723. semaphore.h
  724. aio_cancel()
  725. aio_error()
  726. aio_fsync()
  727. aio_read()
  728. lio_listio()
  729. aio_return()
  730. aio_suspend()
  731. aio_write()
  732. clock_getres(), clock_gettime(), clock_settime()
  733. fdatasync()
  734. mlockall(), munlockall()
  735. mlock(), munlock()
  736. mq_close()
  737. mq_getattr()
  738. mq_notify()
  739. mq_open()
  740. mq_receive()
  741. mq_send()
  742. mq_setattr()
  743. mq_unlink()
  744. nanosleep()
  745. sched_getparam()
  746. sched_get_priority_max(), sched_get_priority_min()
  747. sched_getscheduler()
  748. sched_rr_get_interval()
  749. sched_setparam()
  750. sched_setscheduler()
  751. sem_close()
  752. sem_destroy()
  753. sem_getvalue()
  754. sem_init()
  755. sem_open()
  756. sem_post()
  757. sem_trywait(), sem_wait()
  758. sem_unlink()
  759. sigqueue()
  760. sigtimedwait(), sigwaitinfo()
  761. timer_create()
  762. timer_delete()
  763. timer_getoverrun(), timer_gettime(), timer_settime()
  764. config UCLIBC_HAS_ADVANCED_REALTIME
  765. bool "Advanced realtime-related family of SUSv functions"
  766. default y
  767. depends on UCLIBC_HAS_REALTIME
  768. help
  769. These functions are part of the Timers option and need not
  770. be available on all implementations.
  771. clock_getcpuclockid()
  772. clock_nanosleep()
  773. mq_timedreceive()
  774. mq_timedsend()
  775. posix_fadvise()
  776. posix_fallocate()
  777. posix_madvise()
  778. posix_memalign()
  779. posix_mem_offset()
  780. posix_spawnattr_destroy(), posix_spawnattr_init()
  781. posix_spawnattr_getflags(), posix_spawnattr_setflags()
  782. posix_spawnattr_getpgroup(), posix_spawnattr_setpgroup()
  783. posix_spawnattr_getschedparam(), posix_spawnattr_setschedparam()
  784. posix_spawnattr_getschedpolicy(), posix_spawnattr_setschedpolicy()
  785. posix_spawnattr_getsigdefault(), posix_spawnattr_setsigdefault()
  786. posix_spawnattr_getsigmask(), posix_spawnattr_setsigmask()
  787. posix_spawn_file_actions_addclose()
  788. posix_spawn_file_actions_adddup2()
  789. posix_spawn_file_actions_addopen()
  790. posix_spawn_file_actions_destroy()
  791. posix_spawn_file_actions_init()
  792. posix_spawn()
  793. posix_spawnp()
  794. posix_typed_mem_get_info()
  795. pthread_mutex_timedlock()
  796. sem_timedwait()
  797. #config UCLIBC_HAS_TERMIOS
  798. # bool "termios functions"
  799. # default y
  800. # help
  801. # Get and set terminal attributes, line control, get and set baud
  802. # rate.
  803. # termios(), tcgetattr(), tcsetattr(), tcsendbreak(), tcdrain(),
  804. # tcflush(), tcflow(), cfmakeraw(), cfgetospeed(), cfgetispeed(),
  805. # cfsetispeed(), cfsetospeed(), cfsetspeed()
  806. #
  807. # If unsure, say Y.
  808. config UCLIBC_HAS_EPOLL
  809. bool "epoll"
  810. default y
  811. help
  812. epoll_create(), epoll_ctl(), epoll_wait() functions.
  813. config UCLIBC_HAS_XATTR
  814. bool "Extended Attributes"
  815. default y
  816. help
  817. Extended Attributes support.
  818. setxattr()
  819. lsetxattr()
  820. fsetxattr()
  821. getxattr()
  822. lgetxattr()
  823. fgetxattr()
  824. listxattr()
  825. llistxattr()
  826. flistxattr()
  827. removexattr()
  828. lremovexattr()
  829. fremovexattr()
  830. Say N unless you need support for extended attributes and the
  831. filesystems do actually support them.
  832. config UCLIBC_HAS_PROFILING
  833. bool "Profiling support"
  834. default y
  835. help
  836. gcc's -finstrument-functions needs these.
  837. Most people can safely answer N.
  838. config UCLIBC_HAS_CRYPT_IMPL
  839. bool "libcrypt support"
  840. default y
  841. help
  842. libcrypt contains crypt(), setkey() and encrypt()
  843. config UCLIBC_HAS_CRYPT_STUB
  844. bool "libcrypt stubs"
  845. default y
  846. depends on !UCLIBC_HAS_CRYPT_IMPL
  847. help
  848. Standards mandate that crypt(3) provides a stub if it is unavailable.
  849. If you enable this option then stubs for
  850. crypt(), setkey() and encrypt()
  851. will be provided in a small libcrypt.
  852. config UCLIBC_HAS_CRYPT
  853. def_bool y
  854. depends on UCLIBC_HAS_CRYPT_IMPL || UCLIBC_HAS_CRYPT_STUB
  855. endmenu
  856. menuconfig UCLIBC_HAS_NETWORK_SUPPORT
  857. bool "Networking Support"
  858. default y
  859. help
  860. Say N here if you do not need network support.
  861. if UCLIBC_HAS_NETWORK_SUPPORT
  862. config UCLIBC_HAS_SOCKET
  863. bool "Socket support"
  864. default y
  865. help
  866. If you want to include support for sockets then answer Y.
  867. config UCLIBC_HAS_IPV4
  868. bool "IP version 4 support"
  869. default y
  870. select UCLIBC_HAS_SOCKET
  871. help
  872. If you want to include support for the Internet Protocol
  873. (IP version 4) then answer Y.
  874. Most people will say Y.
  875. config UCLIBC_HAS_IPV6
  876. bool "IP version 6 support"
  877. default n
  878. select UCLIBC_HAS_SOCKET
  879. help
  880. If you want to include support for the next version of the Internet
  881. Protocol (IP version 6) then answer Y.
  882. Most people should answer N.
  883. config UCLIBC_HAS_RPC
  884. bool "Remote Procedure Call (RPC) support"
  885. default n
  886. # RPC+socket-ipvX doesn't currently work.
  887. depends on UCLIBC_HAS_IPV4 || UCLIBC_HAS_IPV6
  888. help
  889. If you want to include RPC support, enable this. RPC is rarely used
  890. for anything except for the NFS filesystem. Unless you plan to use
  891. NFS, you can probably leave this set to N and save some space.
  892. If you need to use NFS then you should answer Y.
  893. config UCLIBC_HAS_FULL_RPC
  894. bool "Full RPC support"
  895. depends on UCLIBC_HAS_RPC
  896. default y if !HAVE_SHARED
  897. help
  898. Normally we enable just enough RPC support for things like rshd and
  899. nfs mounts to work. If you find you need the rest of the RPC stuff,
  900. then enable this option. Most people can safely answer N.
  901. config UCLIBC_HAS_REENTRANT_RPC
  902. bool "Reentrant RPC support"
  903. depends on UCLIBC_HAS_RPC
  904. default y if !HAVE_SHARED
  905. help
  906. Most packages utilize the normal (non-reentrant) RPC functions, but
  907. some (like exportfs from nfs-utils) need these reentrant versions.
  908. Most people can safely answer N.
  909. config UCLIBC_USE_NETLINK
  910. bool "Use netlink to query interfaces"
  911. default n
  912. depends on UCLIBC_HAS_SOCKET
  913. help
  914. In newer versions of Linux (2.4.17+), support was added for querying
  915. network device information via netlink rather than the old style
  916. ioctl's. Most of the time, the older ioctl style is sufficient (and
  917. it is smaller than netlink), but if you find that not all of your
  918. devices are being returned by the if_nameindex() function, you will
  919. have to use the netlink implementation.
  920. Most people can safely answer N.
  921. config UCLIBC_SUPPORT_AI_ADDRCONFIG
  922. bool "Support the AI_ADDRCONFIG flag"
  923. depends on UCLIBC_USE_NETLINK
  924. default n
  925. help
  926. The implementation of AI_ADDRCONFIG is aligned with the glibc
  927. implementation using netlink to query interfaces to find both
  928. ipv4 and ipv6 support. This is only needed if an application uses
  929. the AI_ADDRCONFIG flag.
  930. Most people can safely answer N.
  931. config UCLIBC_HAS_BSD_RES_CLOSE
  932. bool "Support res_close() (bsd-compat)"
  933. default n
  934. help
  935. Answer Y if you desperately want to support BSD compatibility in
  936. the network code.
  937. Most people will say N.
  938. config UCLIBC_HAS_COMPAT_RES_STATE
  939. bool "Use compatible but bloated _res"
  940. default y
  941. help
  942. Answer Y if you build network utilities and they muck with resolver
  943. internals a lot (_res global structure). uclibc does not use most
  944. of _res.XXX fields, and with this option OFF they won't even exist.
  945. Which will make e.g. dig build fail.
  946. Answering N saves around 400 bytes in bss.
  947. config UCLIBC_HAS_EXTRA_COMPAT_RES_STATE
  948. bool "Use extra compatible but extra bloated _res"
  949. default n
  950. help
  951. Answer Y if selecting UCLIBC_HAS_COMPAT_RES_STATE is not enough.
  952. As far as I can say, this should never be needed.
  953. endif
  954. menu "String and Stdio Support"
  955. config UCLIBC_HAS_STRING_GENERIC_OPT
  956. bool "Use faster (but larger) generic string functions"
  957. default y
  958. help
  959. Answer Y to use the (tweaked) glibc generic string functions.
  960. In general, they are faster (but 3-5K larger) than the base
  961. uClibc string functions which are optimized solely for size.
  962. Many people will answer Y.
  963. config UCLIBC_HAS_STRING_ARCH_OPT
  964. bool "Use arch-specific assembly string functions (where available)"
  965. default y
  966. help
  967. Answer Y to use any archtecture-specific assembly language string
  968. functions available for this target plaform.
  969. Note that assembly implementations are not available for all string
  970. functions, so some generic (written in C) string functions may
  971. still be used.
  972. These are small and fast, the only reason _not_ to say Y here is
  973. for debugging purposes.
  974. config UCLIBC_HAS_CTYPE_TABLES
  975. bool "Use Table Versions Of 'ctype.h' Functions."
  976. default y
  977. help
  978. Answer Y to use table versions of the 'ctype.h' functions.
  979. While the non-table versions are often smaller when building
  980. statically linked apps, they work only in stub locale mode.
  981. Most people will answer Y.
  982. config UCLIBC_HAS_CTYPE_SIGNED
  983. bool "Support Signed Characters In 'ctype.h' Functions."
  984. depends on UCLIBC_HAS_CTYPE_TABLES
  985. default y
  986. help
  987. Answer Y to enable support for passing signed char values to
  988. the 'ctype.h' functions. ANSI/ISO C99 and SUSv3 specify that
  989. these functions are only defined for unsigned char values and
  990. EOF. However, glibc allows negative signed char values as well
  991. in order to support 'broken old programs'.
  992. Most people will answer Y.
  993. choice
  994. prompt "ctype argument checking"
  995. depends on UCLIBC_HAS_CTYPE_TABLES
  996. default UCLIBC_HAS_CTYPE_UNSAFE
  997. help
  998. Please select the invalid arg behavior you want for the 'ctype'
  999. functions.
  1000. The 'ctype' functions are now implemented using table lookups, with
  1001. the arg being the index. This can result in incorrect memory accesses
  1002. or even segfaults for args outside of the allowed range.
  1003. NOTE: This only affects the 'ctype' _functions_. It does not affect
  1004. the macro implementations.
  1005. config UCLIBC_HAS_CTYPE_UNSAFE
  1006. bool "Do not check -- unsafe"
  1007. config UCLIBC_HAS_CTYPE_CHECKED
  1008. bool "Detect and handle appropriately"
  1009. config UCLIBC_HAS_CTYPE_ENFORCED
  1010. bool "Issue a diagnostic and abort()"
  1011. endchoice
  1012. config UCLIBC_HAS_WCHAR
  1013. bool "Wide Character Support"
  1014. default n
  1015. help
  1016. Answer Y to enable wide character support. This will make uClibc
  1017. much larger. It is also currently required for locale support.
  1018. Most people will answer N.
  1019. config UCLIBC_HAS_LOCALE
  1020. bool "Locale Support"
  1021. select UCLIBC_HAS_WCHAR
  1022. select UCLIBC_HAS_CTYPE_TABLES
  1023. default n
  1024. help
  1025. uClibc now has full ANSI/ISO C99 locale support (except for
  1026. wcsftime() and collating items in regex). Be aware that enabling
  1027. this option will make uClibc much larger.
  1028. Enabling UCLIBC_HAS_LOCALE with the default set of supported locales
  1029. (169 UTF-8 locales, and 144 locales for other codesets) will enlarge
  1030. uClibc by around 300k. You can reduce this size by building your own
  1031. custom set of locate data (see extra/locale/LOCALES for details).
  1032. uClibc's locale support is still under development. For example,
  1033. codesets using shift states are not currently supported. Support is
  1034. planned in the next iteration of locale support.
  1035. Answer Y to enable locale support. Most people will answer N.
  1036. config UCLIBC_PREGENERATED_LOCALE_DATA
  1037. bool "Use Pre-generated Locale Data"
  1038. depends on UCLIBC_HAS_LOCALE
  1039. default n
  1040. help
  1041. Use pre-built locale data.
  1042. Note that these pregenerated locales are sensitive to your
  1043. target architecture (endianess, bitcount).
  1044. Saying N here is highly recommended.
  1045. config UCLIBC_DOWNLOAD_PREGENERATED_LOCALE_DATA
  1046. bool "Automagically Download the Pre-generated Locale Data (if necessary)"
  1047. depends on UCLIBC_PREGENERATED_LOCALE_DATA
  1048. default n
  1049. help
  1050. If you would like the build process to use 'wget' to automatically
  1051. download the pregenerated locale data, enable this option. Otherwise
  1052. you will need to obtain the locale data yourself from:
  1053. http://www.uclibc.org/downloads/uClibc-locale-*.tgz
  1054. and place the uClibc-locale-*.tgz tarball in the extra/locale/
  1055. directory.
  1056. Go ahead and make life easy for yourself... Answer Y.
  1057. config UCLIBC_HAS_XLOCALE
  1058. bool "Extended Locale Support (experimental/incomplete)"
  1059. depends on UCLIBC_HAS_LOCALE
  1060. default n
  1061. help
  1062. Answer Y to enable extended locale support similar to that provided
  1063. by glibc. This is primarily intended to support libstd++
  1064. functionality.
  1065. However, it also allows thread-specific locale selection via
  1066. uselocale().
  1067. Most people will answer N.
  1068. config UCLIBC_HAS_HEXADECIMAL_FLOATS
  1069. bool "Support hexadecimal float notation"
  1070. depends on UCLIBC_HAS_CTYPE_TABLES
  1071. depends on UCLIBC_HAS_FLOATS
  1072. default n
  1073. help
  1074. Answer Y to enable support for hexadecimal float notation in the
  1075. (wchar and) char string to floating point conversion functions, as
  1076. well as support for the %a and %A conversion specifiers in the
  1077. *printf() and *scanf() functions.
  1078. Most people will answer N.
  1079. config UCLIBC_HAS_GLIBC_DIGIT_GROUPING
  1080. bool "Support glibc's \"'\" flag for allowing locale-specific digit grouping"
  1081. depends on UCLIBC_HAS_LOCALE
  1082. depends on UCLIBC_HAS_FLOATS
  1083. default n
  1084. help
  1085. Answer Y to enable support for glibc's \"'\" flag for allowing
  1086. locale-specific digit grouping in base 10 integer conversions and
  1087. appropriate floating point conversions in the *printf() and *scanf()
  1088. functions.
  1089. Most people will answer N.
  1090. config UCLIBC_HAS_SCANF_LENIENT_DIGIT_GROUPING
  1091. bool "Do not require digit grouping when the \"'\" flag is specified"
  1092. depends on UCLIBC_HAS_GLIBC_DIGIT_GROUPING
  1093. default y
  1094. help
  1095. Answer Y to make digit grouping optional when the \"'\" flag is
  1096. specified.
  1097. This is the standard glibc behavior. If the initial string of digits
  1098. exceeds the maximum group number, the input will be treated as a
  1099. normal non-grouped number.
  1100. Most people will answer N.
  1101. config UCLIBC_HAS_GLIBC_CUSTOM_PRINTF
  1102. bool "Support glibc's register_printf_function() (glibc-compat)"
  1103. depends on !USE_OLD_VFPRINTF
  1104. default n
  1105. help
  1106. Answer Y to support glibc's register_printf_function() to allow an
  1107. application to add its own printf conversion specifiers.
  1108. NOTE: Limits the number or registered specifiers to 10.
  1109. NOTE: Requires new conversion specifiers to be ASCII
  1110. characters (0-0x7f). This is to avoid problems with processing
  1111. format strings in locales with different multibyte conversions.
  1112. Most people will answer N.
  1113. config USE_OLD_VFPRINTF
  1114. bool "Use the old vfprintf implementation"
  1115. depends on !UCLIBC_HAS_WCHAR
  1116. default n
  1117. help
  1118. Set to true to use the old vfprintf instead of the new. This is
  1119. roughly C89 compliant with some extensions, and is much smaller.
  1120. However, it does not support wide chars, positional args, or glibc
  1121. custom printf specifiers.
  1122. Most people will answer N.
  1123. config UCLIBC_PRINTF_SCANF_POSITIONAL_ARGS
  1124. int "Maximum number of positional args. Either 0 or >= 9."
  1125. depends on !USE_OLD_VFPRINTF
  1126. default 9
  1127. help
  1128. Set the maximum number of positional args supported by the
  1129. printf/scanf functions. The Single Unix Specification Version 3
  1130. requires a minimum value of 9. Setting this to a value lower than
  1131. 9 will disable positional arg support and cause the NL_ARGMAX macro
  1132. in limits.h to be #undef'd.
  1133. WARNING! The workspace to support positional args is currently
  1134. allocated on the stack. You probably don't want to set
  1135. this to too high a value.
  1136. Most people will answer 9.
  1137. config UCLIBC_HAS_SCANF_GLIBC_A_FLAG
  1138. bool "Support glibc's 'a' flag for scanf string conversions (not implemented)"
  1139. default n
  1140. help
  1141. NOTE!!! Currently Not Implemented!!! Just A Place Holder!! NOTE!!!
  1142. NOTE!!! Conflicts with an ANSI/ISO C99 scanf flag!! NOTE!!!
  1143. Answer Y to enable support for glibc's 'a' flag for the scanf string
  1144. conversions '%s', '%[', '%ls', '%l[', and '%S'. This is used to
  1145. auto-allocate sufficient memory to hold the data retrieved.
  1146. Most people will answer N.
  1147. choice
  1148. prompt "Stdio buffer size"
  1149. default UCLIBC_HAS_STDIO_BUFSIZ_4096
  1150. help
  1151. Please select a value for BUFSIZ. This will be used by the
  1152. stdio subsystem as the default buffer size for a file, and
  1153. affects fopen(), setvbuf(), etc.
  1154. NOTE: Setting this to 'none' will disable buffering completely.
  1155. However, BUFSIZ will still be defined in stdio.h as 256 because
  1156. many applications use this value.
  1157. config UCLIBC_HAS_STDIO_BUFSIZ_NONE
  1158. bool "none (WARNING - BUFSIZ will be 256 in stdio.h)"
  1159. depends on !UCLIBC_HAS_WCHAR
  1160. config UCLIBC_HAS_STDIO_BUFSIZ_256
  1161. bool "256 (minimum ANSI/ISO C99 value)"
  1162. config UCLIBC_HAS_STDIO_BUFSIZ_512
  1163. bool "512"
  1164. config UCLIBC_HAS_STDIO_BUFSIZ_1024
  1165. bool "1024"
  1166. config UCLIBC_HAS_STDIO_BUFSIZ_2048
  1167. bool "2048"
  1168. config UCLIBC_HAS_STDIO_BUFSIZ_4096
  1169. bool "4096"
  1170. config UCLIBC_HAS_STDIO_BUFSIZ_8192
  1171. bool "8192"
  1172. # If you add more choices, you will need to update uClibc_stdio.h.
  1173. endchoice
  1174. choice
  1175. prompt "Stdio builtin buffer size (uClibc-specific)"
  1176. depends on !UCLIBC_HAS_STDIO_BUFSIZ_NONE
  1177. default UCLIBC_HAS_STDIO_BUILTIN_BUFFER_NONE
  1178. help
  1179. When a FILE is created with fopen(), an attempt is made to allocate
  1180. a BUFSIZ buffer for it. If the allocation fails, fopen() will still
  1181. succeed but the FILE will be unbuffered.
  1182. This option adds a small amount of space to each FILE to act as an
  1183. emergency buffer in the event of a buffer allocation failure.
  1184. Most people will answer None.
  1185. config UCLIBC_HAS_STDIO_BUILTIN_BUFFER_NONE
  1186. bool "None"
  1187. config UCLIBC_HAS_STDIO_BUILTIN_BUFFER_4
  1188. bool "4"
  1189. config UCLIBC_HAS_STDIO_BUILTIN_BUFFER_8
  1190. bool "8"
  1191. # If you add more choices, you will need to update uClibc_stdio.h.
  1192. endchoice
  1193. config UCLIBC_HAS_STDIO_SHUTDOWN_ON_ABORT
  1194. bool "Attempt to shutdown stdio subsystem when abort() is called."
  1195. default n
  1196. help
  1197. ANSI/ISO C99 requires abort() to be asyn-signal-safe. So there was
  1198. a behavioral change made in SUSv3. Previously, abort() was required
  1199. to have the affect of fclose() on all open streams. The wording has
  1200. been changed to "may" from "shall".
  1201. Most people will answer N.
  1202. config UCLIBC_HAS_STDIO_GETC_MACRO
  1203. bool "Provide a macro version of getc()"
  1204. depends on !UCLIBC_HAS_STDIO_BUFSIZ_NONE
  1205. default y
  1206. help
  1207. Provide a macro version of getc().
  1208. Most people will answer Y.
  1209. config UCLIBC_HAS_STDIO_PUTC_MACRO
  1210. bool "Provide a macro version of putc()"
  1211. depends on !UCLIBC_HAS_STDIO_BUFSIZ_NONE
  1212. default y
  1213. help
  1214. Provide a macro version of putc().
  1215. Most people will answer Y.
  1216. config UCLIBC_HAS_STDIO_AUTO_RW_TRANSITION
  1217. bool "Support auto-r/w transition"
  1218. default y
  1219. help
  1220. Answer Y to enable the stdio subsystem to automaticly transition
  1221. between reading and writing. This relaxes the ANSI/ISO C99
  1222. requirement:
  1223. When a file is opened with update mode ('+' as the second or third
  1224. character in the list of mode argument values), both input and output
  1225. may be performed on the associated stream. However, output shall not
  1226. be directly followed by input without an intervening call to the
  1227. fflush function or to a file positioning function (fseek, fsetpos,
  1228. or rewind), and input shall not be directly followed by output without
  1229. an intervening call to a file positioning function, unless the input
  1230. operation encounters end­of­file.
  1231. Most people will answer Y.
  1232. config UCLIBC_HAS_FOPEN_LARGEFILE_MODE
  1233. bool "Support an fopen() 'F' flag for large file mode (uClibc-specific)"
  1234. depends on UCLIBC_HAS_LFS
  1235. default n
  1236. help
  1237. Answer Y to enable a uClibc-specific extension to allow passing an
  1238. additional 'F' flag in the mode string for fopen() to specify that
  1239. the file should be open()ed with the O_LARGEFILE flag set.
  1240. Most people will answer N.
  1241. config UCLIBC_HAS_FOPEN_EXCLUSIVE_MODE
  1242. bool "Support an fopen() 'x' flag for exclusive mode (glibc-compat)"
  1243. default n
  1244. help
  1245. Answer Y to support a glibc extension to allow passing
  1246. additional 'x' flag in the mode string for fopen() to specify that
  1247. the file should be open()ed with the O_EXCL flag set.
  1248. Most people will answer N.
  1249. config UCLIBC_HAS_GLIBC_CUSTOM_STREAMS
  1250. bool "Support fmemopen(), open_memstream(), and fopencookie() (glibc-compat)"
  1251. default n
  1252. help
  1253. Answer Y to support the glibc 'custom stream' extension functions
  1254. fmemopen(), open_memstream(), and fopencookie().
  1255. NOTE: There are some minor differences regarding seeking behavior.
  1256. Most people will answer N.
  1257. config UCLIBC_HAS_PRINTF_M_SPEC
  1258. bool "Support the '%m' specifier in printf format strings (glibc-compat)"
  1259. default n
  1260. help
  1261. Answer Y to support a glibc extension to interpret '%m' in printf
  1262. format strings as an instruction to output the error message string
  1263. (as generated by strerror) corresponding to the current value of
  1264. 'errno'.
  1265. Most people will answer N.
  1266. config UCLIBC_HAS_ERRNO_MESSAGES
  1267. bool "Include the errno message text in the library"
  1268. default y
  1269. help
  1270. Answer Y if you want to include the errno message text in the
  1271. library. This adds about 3K to the library, but enables strerror()
  1272. to generate text other than 'Unknown error <number>'.
  1273. Most people will answer Y.
  1274. config UCLIBC_HAS_SYS_ERRLIST
  1275. bool "Support sys_errlist[] (obsolete-compat)"
  1276. depends on UCLIBC_HAS_ERRNO_MESSAGES
  1277. default n
  1278. help
  1279. Answer Y if you want to support the obsolete sys_errlist[].
  1280. This adds about 0.5k to the library, except for the mips
  1281. arch where it adds over 4K.
  1282. WARNING! In the future, support for sys_errlist[] may be unavailable
  1283. in at least some configurations. In fact, it may be removed
  1284. altogether.
  1285. Most people will answer N.
  1286. Application writers: use the strerror(3) function.
  1287. config UCLIBC_HAS_SIGNUM_MESSAGES
  1288. bool "Include the signum message text in the library"
  1289. default y
  1290. help
  1291. Answer Y if you want to include the signum message text in the
  1292. library. This adds about 0.5K to the library, but enables strsignal()
  1293. to generate text other than 'Unknown signal <number>'.
  1294. Most people will answer Y.
  1295. config UCLIBC_HAS_SYS_SIGLIST
  1296. bool "Support sys_siglist[] (bsd-compat)"
  1297. depends on UCLIBC_HAS_SIGNUM_MESSAGES
  1298. default n
  1299. help
  1300. Answer Y if you want to support sys_siglist[].
  1301. WARNING! In the future, support for sys_siglist[] may be unavailable
  1302. in at least some configurations. In fact, it may be removed
  1303. altogether.
  1304. Most people will answer N.
  1305. config UCLIBC_HAS_GETTEXT_AWARENESS
  1306. bool "Include gettext awareness"
  1307. depends on UCLIBC_HAS_LOCALE && UCLIBC_MJN3_ONLY
  1308. default n
  1309. help
  1310. NOTE!!! Not yet integrated with strerror and strsignal. NOTE!!!
  1311. Answer Y if you want to include weak stub gettext support and
  1312. make the *strerror*() and strsignal() functions gettext-aware.
  1313. Currently, to get functional gettext functionality you will need
  1314. to use gnu gettext.
  1315. Most people will answer N.
  1316. config UCLIBC_HAS_GNU_GETOPT
  1317. bool "Support gnu getopt"
  1318. default y
  1319. help
  1320. Answer Y if you want to include full gnu getopt() instead of a
  1321. (much smaller) SUSv3 compatible getopt().
  1322. Most people will answer Y.
  1323. config UCLIBC_HAS_STDIO_FUTEXES
  1324. bool "Use futexes for multithreaded I/O locking"
  1325. default n
  1326. depends on UCLIBC_HAS_THREADS_NATIVE
  1327. help
  1328. If you want to compile uClibc to use futexes for low-level
  1329. I/O locking, answer Y. Otherwise, answer N.
  1330. config UCLIBC_HAS_GETOPT_LONG
  1331. bool "Support getopt_long/getopt_long_only"
  1332. depends on !UCLIBC_HAS_GNU_GETOPT
  1333. default y
  1334. help
  1335. Answer Y if you want to include getopt_long[_only() used by many
  1336. apps, even busybox.
  1337. Most people will answer Y.
  1338. config UCLIBC_HAS_GNU_GETSUBOPT
  1339. bool "Support glibc getsubopt"
  1340. default y
  1341. help
  1342. Answer Y if you want to include glibc getsubopt() instead of a
  1343. smaller SUSv3 compatible getsubopt().
  1344. Most people will answer Y.
  1345. endmenu
  1346. menu "Big and Tall"
  1347. config UCLIBC_HAS_REGEX
  1348. bool "Regular Expression Support"
  1349. default y
  1350. help
  1351. POSIX regular expression code is really big -- 53k all by itself.
  1352. If you don't use regular expressions, turn this off and save space.
  1353. Of course, if you only statically link, leave this on, since it will
  1354. only be included in your apps if you use regular expressions.
  1355. config UCLIBC_HAS_REGEX_OLD
  1356. bool "Use the older (stable) regular expression code"
  1357. depends on UCLIBC_HAS_REGEX
  1358. default y
  1359. help
  1360. There are two versions of regex. The older (stable) version has
  1361. been in uClibc for quite a long time but hasn't seen too many
  1362. updates. It also has some known issues when dealing with uncommon
  1363. corner cases and multibyte/unicode strings. However, it is quite
  1364. a bit smaller than the newer version.
  1365. If the older version has worked for you and you don't need unicode
  1366. support, then stick with the old version (and say Y here).
  1367. Otherwise, you should use the new version (and say N here).
  1368. config UCLIBC_HAS_FNMATCH
  1369. bool "fnmatch Support"
  1370. default y
  1371. help
  1372. POSIX fnmatch.
  1373. config UCLIBC_HAS_FNMATCH_OLD
  1374. bool "Use the older (stable) fnmatch code"
  1375. depends on UCLIBC_HAS_FNMATCH
  1376. default y
  1377. help
  1378. There are two versions of fnmatch. The older (stable) version has
  1379. been in uClibc for quite a long time but hasn't seen too many
  1380. updates. It also has some known issues when dealing with uncommon
  1381. corner cases and multibyte/unicode strings. However, it is quite
  1382. a bit smaller than the newer version.
  1383. If the older version has worked for you and you don't need unicode
  1384. support, then stick with the old version (and say Y here).
  1385. Otherwise, you should use the new version (and say N here).
  1386. config UCLIBC_HAS_WORDEXP
  1387. bool "Support the wordexp() interface"
  1388. depends on UCLIBC_HAS_GLOB
  1389. default n
  1390. help
  1391. The SuSv3 wordexp() interface performs word expansions per the Shell
  1392. and Utilities volume of IEEE Std 1003.1-2001, Section 2.6. It is
  1393. intended for use by applications that want to implement all of the
  1394. standard Bourne shell expansions on input data.
  1395. This interface is rarely used, and very large. Unless you have a
  1396. pressing need for wordexp(), you should probably answer N.
  1397. config UCLIBC_HAS_FTW
  1398. bool "Support the ftw() and nftw() interfaces"
  1399. default n
  1400. help
  1401. The SuSv3 ftw() and nftw() interfaces are used to recursively descend
  1402. directory paths while repeatedly calling a function.
  1403. This interface is rarely used, and adds around 4.5k. Unless you have
  1404. a pressing need for ftw() or nftw(), you should probably answer N.
  1405. config UCLIBC_HAS_GLOB
  1406. bool "Support the glob() interface"
  1407. depends on UCLIBC_HAS_FNMATCH
  1408. default y
  1409. help
  1410. The glob interface is somewhat large (weighing in at about 2,5k). It
  1411. is used fairly often, but is an option since people wanting to go for
  1412. absolute minimum size may wish to omit it.
  1413. Most people will answer Y.
  1414. config UCLIBC_HAS_GNU_GLOB
  1415. bool "Support gnu glob() interface"
  1416. depends on UCLIBC_HAS_GLOB
  1417. default n
  1418. help
  1419. The gnu glob interface is somewhat larger (weighing in at about 4,2k)
  1420. than it's SuSv3 counterpart (and is out of date). It is an old copy
  1421. from glibc and does not support all the GNU specific options.
  1422. Answer Y if you want to include full gnu glob() instead of the smaller
  1423. SUSv3 compatible glob().
  1424. Most people will answer N.
  1425. endmenu
  1426. menu "Library Installation Options"
  1427. config SHARED_LIB_LOADER_PREFIX
  1428. string "Shared library loader path"
  1429. depends on HAVE_SHARED
  1430. default "$(RUNTIME_PREFIX)lib"
  1431. help
  1432. When using shared libraries, this path is the location where the
  1433. shared library will be invoked. This value will be compiled into
  1434. every binary compiled with uClibc.
  1435. For a typical target system this should be set to "/lib", such that
  1436. 'make install' will install /lib/ld-uClibc.so.0.
  1437. BIG FAT WARNING:
  1438. If you do not have a shared library loader with the correct name
  1439. sitting in the directory this points to, your binaries will not
  1440. run.
  1441. config RUNTIME_PREFIX
  1442. string "uClibc runtime library directory"
  1443. default "/usr/$(TARGET_ARCH)-linux-uclibc/"
  1444. help
  1445. RUNTIME_PREFIX is the directory into which the uClibc runtime
  1446. libraries will be installed. The result will look something
  1447. like the following:
  1448. $(RUNTIME_PREFIX)/
  1449. lib/ <contains all runtime libraries>
  1450. usr/bin/ldd <the ldd utility program>
  1451. sbin/ldconfig <the ldconfig utility program>
  1452. This value is used by the 'make install' Makefile target. Since this
  1453. directory is compiled into the shared library loader, you will need to
  1454. recompile uClibc if you change this value...
  1455. For a typical target system this should be set to "/", such that
  1456. 'make install' will install /lib/libuClibc-<VERSION>.so
  1457. config DEVEL_PREFIX
  1458. string "uClibc development environment directory"
  1459. default "/usr/$(TARGET_ARCH)-linux-uclibc/usr/"
  1460. help
  1461. DEVEL_PREFIX is the directory into which the uClibc development
  1462. environment will be installed. The result will look something
  1463. like the following:
  1464. $(DEVEL_PREFIX)/
  1465. lib/ <contains static libs>
  1466. include/ <Where all the header files go>
  1467. This value is used by the 'make install' Makefile target when
  1468. installing a uClibc development environment.
  1469. For a typical target system this should be set to "/usr", such that
  1470. 'make install' will install /usr/include/<header files>.
  1471. config HARDWIRED_ABSPATH
  1472. bool "Hardwire absolute paths into linker scripts"
  1473. default y
  1474. help
  1475. This prepends absolute paths to the libraries mentioned in linker
  1476. scripts such as libc.so.
  1477. This is a build time optimization. It has no impact on dynamic
  1478. linking at runtime, which doesn't use linker scripts.
  1479. You must disable this to use uClibc with a relocatable toolchain,
  1480. such as the prebuilt binary cross compilers at
  1481. http://uclibc.org/downloads/binaries which may be installed at an
  1482. arbitrary location (such as in a user's home directory).
  1483. The amount of time saved by this optimization is actually too small to
  1484. measure. The linker just had to search the library path to find the
  1485. linker script, so the dentries are cache hot if it has to search the
  1486. same path again. But it's what glibc does, so we do it too.
  1487. endmenu
  1488. menu "Security options"
  1489. config UCLIBC_BUILD_PIE
  1490. bool "Build utilities as ET_DYN/PIE executables"
  1491. depends on HAVE_SHARED
  1492. depends on TARGET_arm || TARGET_frv || TARGET_i386 || TARGET_mips || TARGET_powerpc
  1493. select FORCE_SHAREABLE_TEXT_SEGMENTS
  1494. default n
  1495. help
  1496. If you answer Y here, ldd and iconv are built as ET_DYN/PIE
  1497. executables.
  1498. It requires gcc-3.4 and binutils-2.15 (for arm 2.16) or later.
  1499. More about ET_DYN/PIE binaries on <http://pax.grsecurity.net/> .
  1500. WARNING: This option also enables FORCE_SHAREABLE_TEXT_SEGMENTS, so
  1501. all libraries have to be built with -fPIC or -fpic, and all
  1502. assembler functions must be written as position independent
  1503. code (PIC).
  1504. config UCLIBC_HAS_ARC4RANDOM
  1505. bool "Include the arc4random() function"
  1506. default n
  1507. help
  1508. Answer Y to support the OpenBSD-like arc4random() function. This
  1509. function picks a random number between 0 and N, and will always return
  1510. something even if the random driver is dead. If urandom fails then
  1511. gettimeofday(2) will be used as the random seed. This function is
  1512. designed to be more dependable than invoking /dev/urandom directly.
  1513. OpenSSL and OpenNTPD currently support this function.
  1514. Most people will answer N.
  1515. config HAVE_NO_SSP
  1516. bool
  1517. default n
  1518. config UCLIBC_HAS_SSP
  1519. bool "Support for GCC stack smashing protector"
  1520. depends on !HAVE_NO_SSP
  1521. default n
  1522. help
  1523. Add code to support GCC's -fstack-protector[-all] option to uClibc.
  1524. This requires GCC 4.1 or newer. GCC does not have to provide libssp,
  1525. the needed functions are added to ldso/libc instead.
  1526. GCC's stack protector is a reimplementation of IBM's propolice.
  1527. See http://www.trl.ibm.com/projects/security/ssp/ and
  1528. http://www.linuxfromscratch.org/hints/downloads/files/ssp.txt
  1529. for details.
  1530. Note that NOEXECSTACK on a kernel with address space randomization
  1531. is generally sufficient to prevent most buffer overflow exploits
  1532. without increasing code size. This option essentially adds debugging
  1533. code to catch them.
  1534. Most people will answer N.
  1535. config UCLIBC_HAS_SSP_COMPAT
  1536. bool "Support for gcc-3.x propolice smashing stack protector"
  1537. depends on UCLIBC_HAS_SSP
  1538. default n
  1539. help
  1540. Add gcc-3.x propolice smashing stack protector to the library.
  1541. This requires a patched version of GCC, supporting the
  1542. -fstack-protector[-all] options, with the __guard and
  1543. __stack_smash_handler functions removed from libgcc.
  1544. These functions are added to ldso/libc instead.
  1545. More information at:
  1546. <http://www.research.ibm.com/trl/projects/security/ssp/>
  1547. Most people will answer N.
  1548. config SSP_QUICK_CANARY
  1549. bool "Use simple guard values without accessing /dev/urandom"
  1550. depends on UCLIBC_HAS_SSP
  1551. default n
  1552. help
  1553. Use gettimeofday(2) to define the __guard without accessing
  1554. /dev/urandom.
  1555. WARNING: This makes smashing stack protector vulnerable to timing
  1556. attacks.
  1557. Most people will answer N.
  1558. choice
  1559. prompt "Propolice protection blocking signal"
  1560. depends on UCLIBC_HAS_SSP
  1561. default PROPOLICE_BLOCK_ABRT if ! DODEBUG
  1562. default PROPOLICE_BLOCK_SEGV if DODEBUG
  1563. help
  1564. "abort" use SIGABRT to block offending programs.
  1565. This is the default implementation.
  1566. "segfault" use SIGSEGV to block offending programs.
  1567. Use this for debugging.
  1568. If unsure, answer "abort".
  1569. config PROPOLICE_BLOCK_ABRT
  1570. bool "abort"
  1571. config PROPOLICE_BLOCK_SEGV
  1572. bool "segfault"
  1573. endchoice
  1574. config UCLIBC_BUILD_SSP
  1575. bool "Build uClibc with -fstack-protector"
  1576. depends on UCLIBC_HAS_SSP
  1577. default n
  1578. help
  1579. Build all uClibc libraries and executables with -fstack-protector,
  1580. adding extra stack overflow checking to most uClibc functions.
  1581. config UCLIBC_BUILD_RELRO
  1582. bool "Build uClibc with linker option -z RELRO"
  1583. depends on HAVE_SHARED
  1584. default y
  1585. help
  1586. Build all libraries and executables with "ld -z relro".
  1587. This tells the linker to mark chunks of an executable or shared
  1588. library read-only after applying dynamic relocations. (This comes
  1589. up when a global const variable is initialized to the address of a
  1590. function or the value of another global variable.)
  1591. This is a fairly obscure option the ld man page doesn't even bother
  1592. to document properly. It's a security paranoia issue that's more
  1593. likely to consume memory (by allocating an extra page) rather than
  1594. save it.
  1595. This is explained in more depth at
  1596. http://www.airs.com/blog/archives/189
  1597. Nobody is likely to care whether you say Y or N here.
  1598. config UCLIBC_BUILD_NOW
  1599. bool "Build uClibc with linker option -z NOW"
  1600. depends on HAVE_SHARED
  1601. default n
  1602. help
  1603. Build all libraries and executables with "ld -z now".
  1604. This tells the linker to resolve all symbols when the library is
  1605. first loaded, rather than when each function is first called. This
  1606. increases start-up latency by a few microseconds and may do
  1607. unnecessary work (resolving symbols that are never used), but the
  1608. realtime people like it for making microbenchmark timings slightly
  1609. more predictable and in some cases it can be slightly faster due to
  1610. CPU cache behavior (not having to fault the linker back in to do
  1611. lazy symbol resolution).
  1612. Most people can't tell the difference between selecting Y or N here.
  1613. config UCLIBC_BUILD_NOEXECSTACK
  1614. bool "Build uClibc with noexecstack marking"
  1615. default y
  1616. help
  1617. Mark all assembler files as noexecstack, which will mark uClibc
  1618. as not requiring an executable stack. (This doesn't prevent other
  1619. files you link against from claiming to need an executable stack, it
  1620. just won't cause uClibc to request it unnecessarily.)
  1621. This is a security thing to make buffer overflows harder to exploit.
  1622. By itself, it's kind of useless, as Linus Torvalds explained in 1998:
  1623. http://old.lwn.net/1998/0806/a/linus-noexec.html
  1624. It only actually provides any security when combined with address
  1625. space randomization, explained here: http://lwn.net/Articles/121845/
  1626. Address space randomization is on by default in current linux
  1627. kernels (although it can be disabled using the option
  1628. CONFIG_COMPAT_BRK).
  1629. You should probably say Y.
  1630. endmenu
  1631. menu "uClibc development/debugging options"
  1632. config CROSS_COMPILER_PREFIX
  1633. string "Cross-compiling toolchain prefix"
  1634. default ""
  1635. help
  1636. The prefix used to execute your cross-compiling toolchain. For
  1637. example, if you run 'arm-linux-uclibc-gcc' to compile something,
  1638. then enter 'arm-linux-uclibc-' here.
  1639. config UCLIBC_EXTRA_CFLAGS
  1640. string "Enter any extra CFLAGS to use to build uClibc"
  1641. default ""
  1642. help
  1643. Add any additional CFLAGS to be used to build uClibc.
  1644. config DODEBUG
  1645. bool "Build uClibc with debugging symbols"
  1646. default n
  1647. select EXTRA_WARNINGS
  1648. help
  1649. Say Y here if you wish to compile uClibc with debugging symbols.
  1650. This will allow you to use a debugger to examine uClibc internals
  1651. while applications are running. This increases the size of the
  1652. library considerably and should only be used when doing development.
  1653. If you are doing development and want to debug uClibc, answer Y.
  1654. Otherwise, answer N.
  1655. config DODEBUG_PT
  1656. bool "Build pthread with debugging output"
  1657. depends on UCLIBC_HAS_THREADS && LINUXTHREADS_OLD
  1658. default n
  1659. help
  1660. Enable debug output in libpthread. This is only useful when doing
  1661. development in libpthread itself.
  1662. Otherwise, answer N.
  1663. config DOSTRIP
  1664. bool "Strip libraries and executables"
  1665. default y
  1666. depends on !DODEBUG
  1667. help
  1668. Say Y here if you do wish to strip all uClibc libraries and
  1669. executables. No stripping increases the size of the binaries
  1670. considerably, but makes it possible to debug uClibc libraries.
  1671. Most people will answer Y.
  1672. config DOASSERTS
  1673. bool "Build uClibc with run-time assertion testing"
  1674. default n
  1675. help
  1676. Say Y here to include runtime assertion tests.
  1677. This enables runtime assertion testing in some code, which can
  1678. increase the size of the library and incur runtime overhead.
  1679. If you say N, then this testing will be disabled.
  1680. config SUPPORT_LD_DEBUG
  1681. bool "Build the shared library loader with debugging support"
  1682. depends on HAVE_SHARED
  1683. default n
  1684. help
  1685. Answer Y here to enable all the extra code needed to debug the uClibc
  1686. native shared library loader. The level of debugging noise that is
  1687. generated depends on the LD_DEBUG environment variable... Just set
  1688. LD_DEBUG to something like: 'LD_DEBUG=token1,token2,.. prog' to
  1689. debug your application. Diagnostic messages will then be printed to
  1690. the stderr.
  1691. For now these debugging tokens are available:
  1692. detail provide more information for some options
  1693. move display copy processing
  1694. symbols display symbol table processing
  1695. reloc display relocation processing; detail shows the
  1696. relocation patch
  1697. nofixups never fixes up jump relocations
  1698. bindings displays the resolve processing (function calls);
  1699. detail shows the relocation patch
  1700. all Enable everything!
  1701. The additional environment variable:
  1702. LD_DEBUG_OUTPUT=file
  1703. redirects the diagnostics to an output file created using
  1704. the specified name and the process id as a suffix.
  1705. An excellent start is simply:
  1706. $ LD_DEBUG=binding,move,symbols,reloc,detail ./appname
  1707. or to log everything to a file named 'logfile', try this
  1708. $ LD_DEBUG=all LD_DEBUG_OUTPUT=logfile ./appname
  1709. If you are doing development and want to debug uClibc's shared library
  1710. loader, answer Y. Mere mortals answer N.
  1711. config SUPPORT_LD_DEBUG_EARLY
  1712. bool "Build the shared library loader with early debugging support"
  1713. depends on HAVE_SHARED
  1714. default n
  1715. help
  1716. Answer Y here to if you find the uClibc shared library loader is
  1717. crashing or otherwise not working very early on. This is typical
  1718. only when starting a new port when you haven't figured out how to
  1719. properly get the values for argc, argv, environ, etc. This method
  1720. allows a degree of visibility into the very early shared library
  1721. loader initialization process. If you are doing development and want
  1722. to debug the uClibc shared library loader early initialization,
  1723. answer Y. Mere mortals answer N.
  1724. config UCLIBC_MALLOC_DEBUGGING
  1725. bool "Build malloc with debugging support"
  1726. depends on MALLOC || MALLOC_STANDARD
  1727. default n
  1728. help
  1729. Answer Y here to compile extra debugging support code into malloc.
  1730. Malloc debugging output may then be enabled at runtime using the
  1731. MALLOC_DEBUG environment variable.
  1732. The value of MALLOC_DEBUG should be an integer, which is interpreted
  1733. as a bitmask with the following bits:
  1734. 1 - do extra consistency checking
  1735. 2 - output messages for malloc/free calls and OS
  1736. allocation calls
  1737. 4 - output messages for the `MMB' layer
  1738. 8 - output messages for internal malloc heap manipulation
  1739. calls
  1740. Because this increases the size of malloc appreciably (due to strings
  1741. etc), you should say N unless you need to debug a malloc problem.
  1742. config WARNINGS
  1743. string "Compiler Warnings"
  1744. default "-Wall"
  1745. help
  1746. Set this to the set of gcc warnings you wish to see while compiling.
  1747. config EXTRA_WARNINGS
  1748. bool "Enable extra annoying warnings"
  1749. default n
  1750. help
  1751. If you wish to build with extra warnings enabled, say Y here.
  1752. config DOMULTI
  1753. bool "Compile all sources at once into an object"
  1754. default n
  1755. help
  1756. Set this to compile all sources at once into an object (IMA).
  1757. This mode of compilation uses alot of memory but may produce
  1758. smaller binaries.
  1759. Note that you need a very recent GCC for this to work, like
  1760. gcc >= 4.3 plus eventually some patches.
  1761. If unsure, keep the default of N.
  1762. config UCLIBC_MJN3_ONLY
  1763. bool "Manuel's hidden warnings"
  1764. default n
  1765. help
  1766. Answer Y here to see all Manuel's personal notes, warnings, and todos.
  1767. Most people will answer N.
  1768. endmenu