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