Config.in 68 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. config DESIRED_TARGET_ARCH
  7. string
  8. option env="ARCH"
  9. choice
  10. prompt "Target Architecture"
  11. default TARGET_alpha if DESIRED_TARGET_ARCH = "alpha"
  12. default TARGET_arm if DESIRED_TARGET_ARCH = "arm"
  13. default TARGET_avr32 if DESIRED_TARGET_ARCH = "avr32"
  14. default TARGET_bfin if DESIRED_TARGET_ARCH = "bfin"
  15. default TARGET_cris if DESIRED_TARGET_ARCH = "cris"
  16. default TARGET_e1 if DESIRED_TARGET_ARCH = "e1"
  17. default TARGET_frv if DESIRED_TARGET_ARCH = "frv"
  18. default TARGET_h8300 if DESIRED_TARGET_ARCH = "h8300"
  19. default TARGET_hppa if DESIRED_TARGET_ARCH = "hppa"
  20. default TARGET_i386 if DESIRED_TARGET_ARCH = "i386"
  21. default TARGET_i960 if DESIRED_TARGET_ARCH = "i960"
  22. default TARGET_ia64 if DESIRED_TARGET_ARCH = "ia64"
  23. default TARGET_m68k if DESIRED_TARGET_ARCH = "m68k"
  24. default TARGET_microblaze if DESIRED_TARGET_ARCH = "microblaze"
  25. default TARGET_mips if DESIRED_TARGET_ARCH = "mips"
  26. default TARGET_nios if DESIRED_TARGET_ARCH = "nios"
  27. default TARGET_nios2 if DESIRED_TARGET_ARCH = "nios2"
  28. default TARGET_powerpc if DESIRED_TARGET_ARCH = "powerpc"
  29. default TARGET_sh if DESIRED_TARGET_ARCH = "sh"
  30. default TARGET_sh64 if DESIRED_TARGET_ARCH = "sh64"
  31. default TARGET_sparc if DESIRED_TARGET_ARCH = "sparc"
  32. default TARGET_v850 if DESIRED_TARGET_ARCH = "v850"
  33. default TARGET_vax if DESIRED_TARGET_ARCH = "vax"
  34. default TARGET_x86_64 if DESIRED_TARGET_ARCH = "x86_64"
  35. default TARGET_xtensa if DESIRED_TARGET_ARCH = "xtensa"
  36. help
  37. The architecture of your target.
  38. config TARGET_alpha
  39. bool "alpha"
  40. config TARGET_arm
  41. bool "arm"
  42. config TARGET_avr32
  43. bool "avr32"
  44. config TARGET_bfin
  45. bool "bfin"
  46. config TARGET_cris
  47. bool "cris"
  48. config TARGET_e1
  49. bool "e1 (BROKEN)"
  50. config TARGET_frv
  51. bool "frv (BROKEN)"
  52. config TARGET_h8300
  53. bool "h8300 (BROKEN)"
  54. config TARGET_hppa
  55. bool "hppa"
  56. config TARGET_i386
  57. bool "i386"
  58. config TARGET_i960
  59. bool "i960 (BROKEN)"
  60. config TARGET_ia64
  61. bool "ia64"
  62. config TARGET_m68k
  63. bool "m68k"
  64. config TARGET_microblaze
  65. bool "microblaze (BROKEN)"
  66. config TARGET_mips
  67. bool "mips"
  68. config TARGET_nios
  69. bool "nios"
  70. config TARGET_nios2
  71. bool "nios2"
  72. config TARGET_powerpc
  73. bool "powerpc"
  74. config TARGET_sh
  75. bool "superh"
  76. config TARGET_sh64
  77. bool "sh64"
  78. config TARGET_sparc
  79. bool "sparc"
  80. config TARGET_v850
  81. bool "v850 (BROKEN)"
  82. config TARGET_vax
  83. bool "vax"
  84. config TARGET_x86_64
  85. bool "x86_64"
  86. config TARGET_xtensa
  87. bool "xtensa"
  88. endchoice
  89. menu "Target Architecture Features and Options"
  90. if TARGET_alpha
  91. source "extra/Configs/Config.alpha"
  92. endif
  93. if TARGET_arm
  94. source "extra/Configs/Config.arm"
  95. endif
  96. if TARGET_avr32
  97. source "extra/Configs/Config.avr32"
  98. endif
  99. if TARGET_bfin
  100. source "extra/Configs/Config.bfin"
  101. endif
  102. if TARGET_cris
  103. source "extra/Configs/Config.cris"
  104. endif
  105. if TARGET_e1
  106. source "extra/Configs/Config.e1"
  107. endif
  108. if TARGET_frv
  109. source "extra/Configs/Config.frv"
  110. endif
  111. if TARGET_h8300
  112. source "extra/Configs/Config.h8300"
  113. endif
  114. if TARGET_hppa
  115. source "extra/Configs/Config.hppa"
  116. endif
  117. if TARGET_i386
  118. source "extra/Configs/Config.i386"
  119. endif
  120. if TARGET_i960
  121. source "extra/Configs/Config.i960"
  122. endif
  123. if TARGET_ia64
  124. source "extra/Configs/Config.ia64"
  125. endif
  126. if TARGET_m68k
  127. source "extra/Configs/Config.m68k"
  128. endif
  129. if TARGET_nios
  130. source "extra/Configs/Config.nios"
  131. endif
  132. if TARGET_nios2
  133. source "extra/Configs/Config.nios2"
  134. endif
  135. if TARGET_microblaze
  136. source "extra/Configs/Config.microblaze"
  137. endif
  138. if TARGET_mips
  139. source "extra/Configs/Config.mips"
  140. endif
  141. if TARGET_powerpc
  142. source "extra/Configs/Config.powerpc"
  143. endif
  144. if TARGET_sh
  145. source "extra/Configs/Config.sh"
  146. endif
  147. if TARGET_sh64
  148. source "extra/Configs/Config.sh64"
  149. endif
  150. if TARGET_sparc
  151. source "extra/Configs/Config.sparc"
  152. endif
  153. if TARGET_v850
  154. source "extra/Configs/Config.v850"
  155. endif
  156. if TARGET_vax
  157. source "extra/Configs/Config.vax"
  158. endif
  159. if TARGET_x86_64
  160. source "extra/Configs/Config.x86_64"
  161. endif
  162. if TARGET_xtensa
  163. source "extra/Configs/Config.xtensa"
  164. endif
  165. config TARGET_SUBARCH
  166. string
  167. default "e500" if CONFIG_E500
  168. default "classic" if CONFIG_CLASSIC
  169. default "sh4" if CONFIG_SH4
  170. default ""
  171. source "extra/Configs/Config.in.arch"
  172. endmenu
  173. menu "General Library Settings"
  174. config HAVE_NO_PIC
  175. bool
  176. default n
  177. config DOPIC
  178. bool "Generate only Position Independent Code (PIC)"
  179. default y
  180. depends on !HAVE_NO_PIC
  181. help
  182. If you wish to build all of uClibc as PIC objects, then answer Y here.
  183. If you are unsure, then you should answer N.
  184. config ARCH_HAS_NO_SHARED
  185. bool
  186. default n
  187. config ARCH_HAS_NO_LDSO
  188. bool
  189. select ARCH_HAS_NO_SHARED
  190. default n
  191. config HAVE_SHARED
  192. bool "Enable support for shared libraries"
  193. depends on !ARCH_HAS_NO_SHARED
  194. default y
  195. help
  196. If you wish to build uClibc with support for shared libraries then
  197. answer Y here. If you only want to build uClibc as a static library,
  198. then answer N.
  199. config FORCE_SHAREABLE_TEXT_SEGMENTS
  200. bool "Only load shared libraries which can share their text segment"
  201. depends on HAVE_SHARED
  202. default n
  203. help
  204. If you answer Y here, the uClibc native shared library loader will
  205. only load shared libraries, which do not need to modify any
  206. non-writable segments. These libraries haven't set the DT_TEXTREL
  207. tag in the dynamic section (==> objdump).
  208. All your libraries must be compiled with -fPIC or -fpic, and all
  209. assembler function must be written as position independent code (PIC).
  210. Enabling this option will make uClibc's shared library loader a
  211. little bit smaller and guarantee that no memory will be wasted by
  212. badly coded shared libraries.
  213. config LDSO_LDD_SUPPORT
  214. bool "Native 'ldd' support"
  215. depends on HAVE_SHARED
  216. default y
  217. help
  218. Enable all the code needed to support traditional ldd,
  219. which executes the shared library loader to resolve all dependencies
  220. and then provide a list of shared libraries that are required for an
  221. application to function. Disabling this option will makes uClibc's
  222. shared library loader a little bit smaller.
  223. Most people will answer Y.
  224. config LDSO_CACHE_SUPPORT
  225. bool "Enable library loader cache (ld.so.conf)"
  226. depends on HAVE_SHARED
  227. default y
  228. help
  229. Enable this to make use of /etc/ld.so.conf, the shared library loader
  230. cache configuration file to support for non-standard library paths.
  231. After updating this file, it is necessary to run 'ldconfig' to update
  232. the /etc/ld.so.cache shared library loader cache file.
  233. config LDSO_PRELOAD_FILE_SUPPORT
  234. bool "Enable library loader preload file (ld.so.preload)"
  235. depends on HAVE_SHARED
  236. default n
  237. help
  238. Enable this to make use of /etc/ld.so.preload. This file contains a
  239. whitespace separated list of shared libraries to be loaded before
  240. the program.
  241. config LDSO_BASE_FILENAME
  242. string "Shared library loader naming prefix"
  243. depends on HAVE_SHARED && (LDSO_CACHE_SUPPORT || LDSO_PRELOAD_FILE_SUPPORT)
  244. default "ld.so"
  245. help
  246. If you wish to support both uClibc and glibc on the same system, it
  247. is necessary to set this to something other than "ld.so" to avoid
  248. conflicts with glibc, which also uses "ld.so". This prevents both
  249. libraries from using the same /etc/ld.so.* files. If you wish to
  250. support both uClibc and glibc on the same system then you should set
  251. this to "ld-uClibc.so".
  252. Most people will leave this set to the default of "ld.so".
  253. WARNING: Changing the default prefix could cause problems with
  254. binutils' ld !
  255. config UCLIBC_STATIC_LDCONFIG
  256. bool "Link ldconfig statically"
  257. depends on HAVE_SHARED
  258. default y
  259. help
  260. Enable this option to statically link the ldconfig binary.
  261. Making ldconfig static can be beneficial if you have a library
  262. problem and need to use ldconfig to recover. Sometimes it is
  263. preferable to instead keep the size of the system down, in which
  264. case you should disable this option.
  265. config LDSO_RUNPATH
  266. bool "Enable ELF RUNPATH tag support"
  267. depends on HAVE_SHARED
  268. default y if LDSO_CACHE_SUPPORT
  269. default n if !LDSO_CACHE_SUPPORT
  270. help
  271. ELF's may have dynamic RPATH/RUNPATH tags. These tags list paths
  272. which extend the library search paths. They are really only useful
  273. if a package installs libraries in non standard locations and
  274. ld.so.conf support is disabled.
  275. Usage of RUNPATH tags is not too common, so disabling this feature
  276. should be safe for most people.
  277. config UCLIBC_CTOR_DTOR
  278. bool "Support global constructors and destructors"
  279. default y
  280. help
  281. If you wish to build uClibc with support for global constructor
  282. (ctor) and global destructor (dtor) support, then answer Y here.
  283. When ctor/dtor support is enabled, binaries linked with uClibc must
  284. also be linked with crtbegin.o and crtend.o which are provided by gcc
  285. (the "*startfile:" and "*endfile:" settings in your gcc specs file
  286. may need to be adjusted to include these files). This support will
  287. also add a small amount of additional size to each binary compiled vs
  288. uClibc. If you will be using uClibc with C++, or if you need the gcc
  289. __attribute__((constructor)) and __attribute__((destructor)) to work,
  290. then you definitely want to answer Y here. If you don't need ctors
  291. or dtors and want your binaries to be as small as possible, then
  292. answer N.
  293. config LDSO_GNU_HASH_SUPPORT
  294. bool "Enable GNU hash style support"
  295. depends on HAVE_SHARED
  296. default n
  297. help
  298. Newest binutils support a new hash style named GNU-hash. The dynamic
  299. linker will use the new GNU-hash section (.gnu.hash) for symbol lookup
  300. if present into the ELF binaries, otherwise it will use the old SysV
  301. hash style (.hash). This ensures that it is completely backward
  302. compatible.
  303. Further, being the hash table implementation self-contained into each
  304. executable and shared libraries, objects with mixed hash style can
  305. peacefully coexist in the same process.
  306. If you want to use this new feature, answer Y
  307. choice
  308. prompt "Thread support"
  309. #default UCLIBC_HAS_THREADS_NATIVE if (TARGET_alpha || TARGET_arm || TARGET_i386 || TARGET_mips || TARGET_powerpc || TARGET_sh || TARGET_sh64)
  310. default HAS_NO_THREADS
  311. help
  312. If you want to compile uClibc with pthread support, then answer Y.
  313. This will increase the size of uClibc by adding a bunch of locking
  314. to critical data structures, and adding extra code to ensure that
  315. functions are properly reentrant.
  316. config HAS_NO_THREADS
  317. bool "none"
  318. help
  319. Disable thread support.
  320. config LINUXTHREADS_OLD
  321. bool "older (stable) version of linuxthreads"
  322. # linuxthreads and linuxthreads.old need nanosleep()
  323. select UCLIBC_HAS_REALTIME
  324. help
  325. There are two versions of linuxthreads. The older (stable) version
  326. has been in uClibc for quite a long time but hasn't seen too many
  327. updates other than bugfixes.
  328. config LINUXTHREADS_NEW
  329. bool "slightly newer version of linuxthreads"
  330. help
  331. The new version has not been tested much, and lacks ports for arches
  332. which glibc does not support (like bfin/frv/etc...), but is based on
  333. the latest code from glibc, so it may be the only choice for the
  334. newer ports (like alpha/amd64/64bit arches and hppa).
  335. config UCLIBC_HAS_THREADS_NATIVE
  336. bool "Native POSIX Threading (NPTL)"
  337. select UCLIBC_HAS_TLS
  338. help
  339. If you want to compile uClibc with NPTL support, then answer Y.
  340. IMPORTANT NOTE! NPTL requires a Linux 2.6 kernel, binutils
  341. at least version 2.16 and GCC with at least version 4.1.0. NPTL
  342. will not work with older versions of any above sources. If you
  343. ignore any of these guidelines, you do so at your own risk. Do
  344. not ask for help on any of the development mailing lists.
  345. !!!! WARNING !!!! BIG FAT WARNING !!!! REALLY BIG FAT WARNING !!!!
  346. This is experimental code and at times it may not even build and
  347. even if it does it might decide to do random damage. This code is
  348. potentially hazardous to your health and sanity. It will remain
  349. that way until further notice at which point this notice will
  350. disappear. Thank you for your support and for not smoking.
  351. endchoice
  352. config UCLIBC_HAS_THREADS
  353. def_bool y if !HAS_NO_THREADS
  354. config UCLIBC_HAS_TLS
  355. bool "Thread-Local Storage"
  356. depends on UCLIBC_HAS_THREADS_NATIVE
  357. default n
  358. help
  359. If you want to enable TLS support then answer Y.
  360. This is fast an efficient way to store per-thread local data
  361. which is not on stack. It needs __thread support enabled in
  362. gcc.
  363. config PTHREADS_DEBUG_SUPPORT
  364. bool "Build pthreads debugging support"
  365. default n
  366. depends on UCLIBC_HAS_THREADS
  367. help
  368. Say Y here if you wish to be able to debug applications that use
  369. uClibc's pthreads library. By enabling this option, a library
  370. named libthread_db will be built. This library will be dlopen()'d
  371. by gdb and will allow gdb to debug the threads in your application.
  372. IMPORTANT NOTE! Because gdb must dlopen() the libthread_db library,
  373. you must compile gdb with uClibc in order for pthread debugging to
  374. work properly.
  375. If you are doing development and want to debug applications using
  376. uClibc's pthread library, answer Y. Otherwise, answer N.
  377. config UCLIBC_HAS_SYSLOG
  378. bool "Syslog support"
  379. default y
  380. depends on UCLIBC_HAS_NETWORK_SUPPORT
  381. select UCLIBC_HAS_SOCKET
  382. help
  383. Support sending messages to the system logger.
  384. This requires socket-support.
  385. config UCLIBC_HAS_LFS
  386. bool "Large File Support"
  387. default y
  388. help
  389. If you wish to build uClibc with support for accessing large files
  390. (i.e. files greater then 2 GiB) then answer Y. Do not enable this
  391. if you are using an older Linux kernel (2.0.x) that lacks large file
  392. support. Enabling this option will increase the size of uClibc.
  393. choice
  394. prompt "Malloc Implementation"
  395. default MALLOC if ! ARCH_USE_MMU
  396. default MALLOC_STANDARD if ARCH_USE_MMU
  397. config MALLOC
  398. bool "malloc"
  399. help
  400. "malloc" use mmap for all allocations and so works very well on
  401. MMU-less systems that do not support the brk() system call. It is
  402. pretty smart about reusing already allocated memory, and minimizing
  403. memory wastage.
  404. This is the default for uClinux MMU-less systems.
  405. config MALLOC_SIMPLE
  406. bool "malloc-simple"
  407. help
  408. "malloc-simple" is trivially simple and slow as molasses. It
  409. was written from scratch for uClibc, and is the simplest possible
  410. (and therefore smallest) malloc implementation.
  411. This uses only the mmap() system call to allocate and free memory,
  412. and does not use the brk() system call at all, making it a fine
  413. choice for MMU-less systems with very limited memory. It's 100%
  414. standards compliant, thread safe, very small, and releases freed
  415. memory back to the OS immediately rather than keeping it in the
  416. process's heap for reallocation. It is also VERY SLOW.
  417. config MALLOC_STANDARD
  418. bool "malloc-standard"
  419. depends on ARCH_USE_MMU
  420. help
  421. "malloc-standard" is derived from the public domain dlmalloc
  422. implementation by Doug Lea. It is quite fast, and is pretty smart
  423. about reusing already allocated memory, and minimizing memory
  424. wastage. This uses brk() for small allocations, while using mmap()
  425. for larger allocations. This is the default malloc implementation
  426. for uClibc.
  427. If unsure, answer "malloc-standard".
  428. endchoice
  429. config MALLOC_GLIBC_COMPAT
  430. bool "Malloc returns live pointer for malloc(0)"
  431. default n
  432. help
  433. The behavior of malloc(0) is listed as implementation-defined by
  434. SuSv3. Glibc returns a valid pointer to something, while uClibc
  435. normally returns NULL. I personally feel glibc's behavior is
  436. not particularly safe, and allows buggy applications to hide very
  437. serious problems.
  438. When this option is enabled, uClibc will act just like glibc, and
  439. return a live pointer when someone calls malloc(0). This pointer
  440. provides a malloc'ed area with a size of 1 byte. This feature is
  441. mostly useful when dealing with applications using autoconf's broken
  442. AC_FUNC_MALLOC macro (which redefines malloc as rpl_malloc if it
  443. does not detect glibc style returning-a-valid-pointer-for-malloc(0)
  444. behavior). Most people can safely answer N.
  445. config UCLIBC_DYNAMIC_ATEXIT
  446. bool "Dynamic atexit() Support"
  447. default y
  448. help
  449. When this option is enabled, uClibc will support an infinite number,
  450. of atexit() and on_exit() functions, limited only by your available
  451. memory. This can be important when uClibc is used with C++, since
  452. global destructors are implemented via atexit(), and it is quite
  453. possible to exceed the default number when this option is disabled.
  454. Enabling this option adds a few bytes, and more significantly makes
  455. atexit and on_exit depend on malloc, which can be bad when compiling
  456. static executables.
  457. Unless you use uClibc with C++, you should probably answer N.
  458. config COMPAT_ATEXIT
  459. bool "Old (visible) atexit Support"
  460. default n
  461. help
  462. Enable this option if you want to update from 0.9.28 to git/0.9.29,
  463. else you will be missing atexit() until you rebuild all apps.
  464. config UCLIBC_SUSV3_LEGACY
  465. bool "Enable SuSv3 LEGACY functions"
  466. default n
  467. #vfork,
  468. # h_errno
  469. # gethostbyaddr
  470. # gethostbyname
  471. help
  472. Enable this option if you want to have SuSv3 LEGACY functions
  473. in the library, else they are replaced by SuSv3 proposed macros.
  474. Currently applies to:
  475. bcmp, bcopy, bzero, index, rindex, ftime,
  476. bsd_signal, (ecvt), (fcvt), gcvt, (getcontext),
  477. (getwd), (makecontext),
  478. mktemp, (pthread_attr_getstackaddr), (pthread_attr_setstackaddr),
  479. scalb, (setcontext), (swapcontext), ualarm, usleep,
  480. wcswcs.
  481. WARNING! ABI incompatibility.
  482. config UCLIBC_SUSV3_LEGACY_MACROS
  483. bool "Enable SuSv3 LEGACY macros"
  484. default n
  485. help
  486. Enable this option if you want to have SuSv3 LEGACY macros.
  487. Currently applies to bcopy/bzero/bcmp/index/rindex et al.
  488. WARNING! ABI incompatibility.
  489. config UCLIBC_SUSV4_LEGACY
  490. bool "Enable SuSv4 LEGACY or obsolescent functions"
  491. default n
  492. help
  493. Enable this option if you want to have SuSv4 LEGACY functions
  494. and macros in the library.
  495. Currently applies to:
  496. - XSI functions:
  497. _longjmp, _setjmp, _tolower, _toupper, ftw, getitimer,
  498. gettimeofday, isascii, pthread_getconcurrency,
  499. pthread_setconcurrency, setitimer, setpgrp, sighold,
  500. sigignore, sigpause, sigrelse, sigset, siginterrupt,
  501. tempnam, toascii, ulimit.
  502. - Base functions:
  503. asctime, asctime_r, ctime, ctime_r, gets, rand_r,
  504. tmpnam, utime.
  505. WARNING! ABI incompatibility.
  506. config UCLIBC_HAS_STUBS
  507. bool "Provide stubs for unavailable functionality"
  508. default n
  509. help
  510. With this option uClibc provides non-functional stubs for
  511. functions which are impossible to implement on the target
  512. architecture. Otherwise, such functions are simply omitted.
  513. As of 2008-07, this option makes uClibc provide fork() stub
  514. on NOMMU targets. It always sets errno to ENOSYS and returns -1.
  515. This may be useful if you port a lot of software and cannot
  516. audit all of it and replace or disable fork() usage.
  517. With this option, a program which uses fork() will build
  518. successfully. Of course, it may be useless if fork()
  519. is essential for its operation.
  520. config UCLIBC_HAS_SHADOW
  521. bool "Shadow Password Support"
  522. default y
  523. help
  524. Answer N if you do not need shadow password support.
  525. Most people will answer Y.
  526. config UCLIBC_HAS_PROGRAM_INVOCATION_NAME
  527. bool "Support for program_invocation_name"
  528. default n
  529. help
  530. Support for the GNU-specific program_invocation_name and
  531. program_invocation_short_name strings. Some GNU packages
  532. (like tar and coreutils) utilize these for extra useful
  533. output, but in general are not required.
  534. At startup, these external strings are automatically set
  535. up based on the value of ARGV[0].
  536. If unsure, just answer N.
  537. config UCLIBC_HAS___PROGNAME
  538. bool "Support for __progname"
  539. default y
  540. depends on UCLIBC_HAS_PROGRAM_INVOCATION_NAME
  541. help
  542. Some packages (like openssh) like to peek into internal libc
  543. symbols to make their output a bit more user friendly.
  544. At startup, __progname is automatically set up based on the
  545. value of ARGV[0].
  546. If unsure, just answer N.
  547. config UCLIBC_HAS_PTY
  548. bool "Support for pseudo-terminals"
  549. default y
  550. help
  551. This enables support for pseudo-terminals (see man 4 pts
  552. and man 7 pty).
  553. If unsure, just answer Y.
  554. config ASSUME_DEVPTS
  555. bool "Assume that /dev/pts is a devpts or devfs file system"
  556. default y
  557. depends on UCLIBC_HAS_PTY
  558. help
  559. Enable this if /dev/pts is on a devpts or devfs filesystem. Both
  560. these filesystems automatically manage permissions on the /dev/pts
  561. devices. You may need to mount your devpts or devfs filesystem on
  562. /dev/pts for this to work.
  563. Most people should answer Y.
  564. config UNIX98PTY_ONLY
  565. bool "Support only Unix 98 PTYs"
  566. default y
  567. depends on UCLIBC_HAS_PTY
  568. help
  569. If you want to support only Unix 98 PTYs enable this. Some older
  570. applications may need this disabled and will thus use legacy BSD
  571. style PTY handling which is more complex and also bigger than
  572. Unix 98 PTY handling.
  573. For most current programs, you can generally answer Y.
  574. if UNIX98PTY_ONLY
  575. config UCLIBC_HAS_GETPT
  576. bool "Support getpt() (glibc-compat)"
  577. default n
  578. depends on UCLIBC_HAS_PTY
  579. help
  580. Some packages may need getpt().
  581. All of those are non-standard and can be considered
  582. GNU/libc compatibility.
  583. Either use posix_openpt() or just open /dev/ptmx yourself.
  584. If unsure, just say N.
  585. endif
  586. if !UNIX98PTY_ONLY
  587. # Have to use __libc_ptyname{1,2}[] and related bloat
  588. config UCLIBC_HAS_GETPT
  589. def_bool y
  590. endif
  591. config UCLIBC_HAS_TM_EXTENSIONS
  592. bool "Support 'struct tm' timezone extension fields"
  593. default y
  594. help
  595. Enabling this option adds fields to 'struct tm' in time.h for
  596. tracking the number of seconds east of UTC, and an abbreviation for
  597. the current timezone. These fields are not specified by the SuSv3
  598. standard, but they are commonly used in both GNU and BSD application
  599. code.
  600. To strictly follow the SuSv3 standard, leave this disabled.
  601. Most people will probably want to answer Y.
  602. config UCLIBC_HAS_TZ_CACHING
  603. bool "Enable caching of the last valid timezone 'TZ' string"
  604. default y
  605. help
  606. Answer Y to enable caching of the last valid 'TZ' string describing
  607. the timezone setting. This allows a quick string compare to avoid
  608. repeated parsing of unchanged 'TZ' strings when tzset() is called.
  609. Most people will answer Y.
  610. config UCLIBC_HAS_TZ_FILE
  611. bool "Enable '/etc/TZ' file support to set a default timezone (uClibc-specific)"
  612. default y
  613. help
  614. Answer Y to enable the setting of a default timezone for uClibc.
  615. Ordinarily, uClibc gets the timezone information exclusively from the
  616. 'TZ' environment variable. In particular, there is no support for
  617. the zoneinfo directory tree or the /etc/timezone file used by glibc.
  618. With this option enabled, uClibc will use the value stored in the
  619. file '/etc/TZ' (default path) to obtain timezone information if the
  620. 'TZ' environment variable is missing or has an invalid value. The
  621. file consists of a single line (newline required) of text describing
  622. the timezone in the format specified for the TZ environment variable.
  623. Doing 'echo CST6CDT > /etc/TZ' is enough to create a valid file.
  624. See
  625. http://www.opengroup.org/onlinepubs/007904975/basedefs/xbd_chap08.html
  626. for details on valid settings of 'TZ'.
  627. Most people will answer Y.
  628. config UCLIBC_HAS_TZ_FILE_READ_MANY
  629. bool "Repeatedly read the '/etc/TZ' file"
  630. depends on UCLIBC_HAS_TZ_FILE
  631. default y
  632. help
  633. Answer Y to enable repeated reading of the '/etc/TZ' file even after
  634. a valid value has been read. This incurs the overhead of an
  635. open/read/close for each tzset() call (explicit or implied). However,
  636. setting this will allow applications to update their timezone
  637. information if the contents of the file change.
  638. Most people will answer Y.
  639. config UCLIBC_TZ_FILE_PATH
  640. string "Path to the 'TZ' file for setting the global timezone"
  641. depends on UCLIBC_HAS_TZ_FILE
  642. default "/etc/TZ"
  643. help
  644. This is the path to the 'TZ' file.
  645. Most people will use the default of '/etc/TZ'.
  646. endmenu
  647. menu "Advanced Library Settings"
  648. config UCLIBC_PWD_BUFFER_SIZE
  649. int "Buffer size for getpwnam() and friends"
  650. default 256
  651. range 12 1024
  652. help
  653. This sets the value of the buffer size for getpwnam() and friends.
  654. By default, this is 256. (For reference, glibc uses 1024).
  655. The value can be found using sysconf() with the _SC_GETPW_R_SIZE_MAX
  656. parameter.
  657. config UCLIBC_GRP_BUFFER_SIZE
  658. int "Buffer size for getgrnam() and friends"
  659. default 256
  660. range 12 1024
  661. help
  662. This sets the value of the buffer size for getgrnam() and friends.
  663. By default, this is 256. (For reference, glibc uses 1024).
  664. The value can be found using sysconf() with the _SC_GETGR_R_SIZE_MAX
  665. parameter.
  666. comment "Support various families of functions"
  667. config UCLIBC_LINUX_MODULE_24
  668. bool "Linux kernel module functions"
  669. default !(TARGET_bfin)
  670. help
  671. create_module, query_module
  672. are used in linux (prior to 2.6) for loadable kernel modules.
  673. Say N if you do not use kernel modules, or you only support
  674. Linux 2.6+.
  675. config UCLIBC_LINUX_SPECIFIC
  676. bool "Linux specific functions"
  677. default y
  678. help
  679. capget(), capset(), fstatfs(), inotify_*(), ioperm(), iopl(),
  680. madvise(), modify_ldt(), personality(), prctl()/arch_prctl(),
  681. ppoll(), readahead(), reboot(), remap_file_pages(),
  682. sched_getaffinity(), sched_setaffinity(), sendfile(),
  683. setfsgid(), setfsuid(), setresuid(),
  684. splice(), vmsplice(), tee(), signalfd(), swapoff(), swapon(),
  685. sync_file_range(), sysctl(), sysinfo(), vhangup()
  686. config UCLIBC_HAS_GNU_ERROR
  687. bool "Support GNU extensions for error-reporting"
  688. default y
  689. help
  690. Support for the GNU-specific error(), error_at_line(),
  691. void (* error_print_progname)(), error_message_count
  692. functions and variables. Some GNU packages
  693. utilize these for extra useful output, but in general
  694. are not required.
  695. If unsure, just answer N.
  696. config UCLIBC_BSD_SPECIFIC
  697. bool "BSD specific functions"
  698. default y
  699. help
  700. mincore(), getdomainname(), setdomainname()
  701. If unsure, say N.
  702. config UCLIBC_HAS_BSD_ERR
  703. bool "BSD err functions"
  704. default y
  705. help
  706. These functions are non-standard BSD extensions.
  707. err(), errx(), warn(), warnx(), verr(), verrx(), vwarn(), vwarnx()
  708. If unsure, say N.
  709. config UCLIBC_HAS_OBSOLETE_BSD_SIGNAL
  710. bool "BSD obsolete signal functions"
  711. default n
  712. help
  713. These functions are provided as a compatibility interface for
  714. programs that make use of the historical System V signal API.
  715. This API is obsolete:
  716. new applications should use the POSIX signal API (sigaction(2),
  717. sigprocmask(2), etc.).
  718. Affected functions:
  719. sigset(), sighold(), sigrelse(), sigignore()
  720. If unsure, say N.
  721. config UCLIBC_HAS_OBSOLETE_SYSV_SIGNAL
  722. bool "SYSV obsolete signal functions"
  723. default n
  724. help
  725. Use of sysv_signal() should be avoided; use sigaction(2) instead.
  726. If unsure, say N.
  727. config UCLIBC_NTP_LEGACY
  728. bool "ntp_*() aliases"
  729. default n
  730. help
  731. Provide legacy aliases for ntp functions:
  732. ntp_adjtime(), ntp_gettime()
  733. It is safe to say N here.
  734. config UCLIBC_SV4_DEPRECATED
  735. bool "Enable SVr4 deprecated functions"
  736. default n
  737. help
  738. These functions are DEPRECATED in System V release 4.
  739. Say N unless you desparately need one of the functions below:
  740. ustat() [use statfs(2) in your code instead]
  741. config UCLIBC_HAS_REALTIME
  742. bool "Realtime-related family of SUSv functions"
  743. default y
  744. help
  745. These functions are part of the Timers option and need not
  746. be available on all implementations.
  747. Includes AIO, message-queue, scheduler, semaphore functions:
  748. aio.h
  749. mqueue.h
  750. sched.h
  751. semaphore.h
  752. aio_cancel()
  753. aio_error()
  754. aio_fsync()
  755. aio_read()
  756. lio_listio()
  757. aio_return()
  758. aio_suspend()
  759. aio_write()
  760. clock_getres(), clock_gettime(), clock_settime()
  761. fdatasync()
  762. mlockall(), munlockall()
  763. mlock(), munlock()
  764. mq_close()
  765. mq_getattr()
  766. mq_notify()
  767. mq_open()
  768. mq_receive()
  769. mq_send()
  770. mq_setattr()
  771. mq_unlink()
  772. nanosleep()
  773. sched_getparam()
  774. sched_get_priority_max(), sched_get_priority_min()
  775. sched_getscheduler()
  776. sched_rr_get_interval()
  777. sched_setparam()
  778. sched_setscheduler()
  779. sem_close()
  780. sem_destroy()
  781. sem_getvalue()
  782. sem_init()
  783. sem_open()
  784. sem_post()
  785. sem_trywait(), sem_wait()
  786. sem_unlink()
  787. sigqueue()
  788. sigtimedwait(), sigwaitinfo()
  789. timer_create()
  790. timer_delete()
  791. timer_getoverrun(), timer_gettime(), timer_settime()
  792. config UCLIBC_HAS_ADVANCED_REALTIME
  793. bool "Advanced realtime-related family of SUSv functions"
  794. default y
  795. depends on UCLIBC_HAS_REALTIME
  796. help
  797. These functions are part of the Timers option and need not
  798. be available on all implementations.
  799. clock_getcpuclockid()
  800. clock_nanosleep()
  801. mq_timedreceive()
  802. mq_timedsend()
  803. posix_fadvise()
  804. posix_fallocate()
  805. posix_madvise()
  806. posix_memalign()
  807. posix_mem_offset()
  808. posix_spawnattr_destroy(), posix_spawnattr_init()
  809. posix_spawnattr_getflags(), posix_spawnattr_setflags()
  810. posix_spawnattr_getpgroup(), posix_spawnattr_setpgroup()
  811. posix_spawnattr_getschedparam(), posix_spawnattr_setschedparam()
  812. posix_spawnattr_getschedpolicy(), posix_spawnattr_setschedpolicy()
  813. posix_spawnattr_getsigdefault(), posix_spawnattr_setsigdefault()
  814. posix_spawnattr_getsigmask(), posix_spawnattr_setsigmask()
  815. posix_spawn_file_actions_addclose()
  816. posix_spawn_file_actions_adddup2()
  817. posix_spawn_file_actions_addopen()
  818. posix_spawn_file_actions_destroy()
  819. posix_spawn_file_actions_init()
  820. posix_spawn()
  821. posix_spawnp()
  822. posix_typed_mem_get_info()
  823. pthread_mutex_timedlock()
  824. sem_timedwait()
  825. #config UCLIBC_HAS_TERMIOS
  826. # bool "termios functions"
  827. # default y
  828. # help
  829. # Get and set terminal attributes, line control, get and set baud
  830. # rate.
  831. # termios(), tcgetattr(), tcsetattr(), tcsendbreak(), tcdrain(),
  832. # tcflush(), tcflow(), cfmakeraw(), cfgetospeed(), cfgetispeed(),
  833. # cfsetispeed(), cfsetospeed(), cfsetspeed()
  834. #
  835. # If unsure, say Y.
  836. config UCLIBC_HAS_EPOLL
  837. bool "epoll"
  838. default y
  839. help
  840. epoll_create(), epoll_ctl(), epoll_wait() functions.
  841. config UCLIBC_HAS_XATTR
  842. bool "Extended Attributes"
  843. default y
  844. help
  845. Extended Attributes support.
  846. setxattr()
  847. lsetxattr()
  848. fsetxattr()
  849. getxattr()
  850. lgetxattr()
  851. fgetxattr()
  852. listxattr()
  853. llistxattr()
  854. flistxattr()
  855. removexattr()
  856. lremovexattr()
  857. fremovexattr()
  858. Say N unless you need support for extended attributes and the
  859. filesystems do actually support them.
  860. config UCLIBC_HAS_PROFILING
  861. bool "Profiling support"
  862. default y
  863. help
  864. gcc's -finstrument-functions needs these.
  865. Most people can safely answer N.
  866. config UCLIBC_HAS_CRYPT_IMPL
  867. bool "libcrypt support"
  868. default y
  869. help
  870. libcrypt contains crypt(), setkey() and encrypt()
  871. config UCLIBC_HAS_CRYPT_STUB
  872. bool "libcrypt stubs"
  873. default y
  874. depends on !UCLIBC_HAS_CRYPT_IMPL
  875. help
  876. Standards mandate that crypt(3) provides a stub if it is unavailable.
  877. If you enable this option then stubs for
  878. crypt(), setkey() and encrypt()
  879. will be provided in a small libcrypt.
  880. config UCLIBC_HAS_CRYPT
  881. def_bool y
  882. depends on UCLIBC_HAS_CRYPT_IMPL || UCLIBC_HAS_CRYPT_STUB
  883. endmenu
  884. menuconfig UCLIBC_HAS_NETWORK_SUPPORT
  885. bool "Networking Support"
  886. default y
  887. help
  888. Say N here if you do not need network support.
  889. if UCLIBC_HAS_NETWORK_SUPPORT
  890. config UCLIBC_HAS_SOCKET
  891. bool "Socket support"
  892. default y
  893. help
  894. If you want to include support for sockets then answer Y.
  895. config UCLIBC_HAS_IPV4
  896. bool "IP version 4 support"
  897. default y
  898. select UCLIBC_HAS_SOCKET
  899. help
  900. If you want to include support for the Internet Protocol
  901. (IP version 4) then answer Y.
  902. Most people will say Y.
  903. config UCLIBC_HAS_IPV6
  904. bool "IP version 6 support"
  905. default n
  906. select UCLIBC_HAS_SOCKET
  907. help
  908. If you want to include support for the next version of the Internet
  909. Protocol (IP version 6) then answer Y.
  910. Most people should answer N.
  911. config UCLIBC_HAS_RPC
  912. bool "Remote Procedure Call (RPC) support"
  913. default n
  914. # RPC+socket-ipvX doesn't currently work.
  915. depends on UCLIBC_HAS_IPV4 || UCLIBC_HAS_IPV6
  916. help
  917. If you want to include RPC support, enable this. RPC is rarely used
  918. for anything except for the NFS filesystem. Unless you plan to use
  919. NFS, you can probably leave this set to N and save some space.
  920. If you need to use NFS then you should answer Y.
  921. config UCLIBC_HAS_FULL_RPC
  922. bool "Full RPC support"
  923. depends on UCLIBC_HAS_RPC
  924. default y if !HAVE_SHARED
  925. help
  926. Normally we enable just enough RPC support for things like rshd and
  927. nfs mounts to work. If you find you need the rest of the RPC stuff,
  928. then enable this option. Most people can safely answer N.
  929. config UCLIBC_HAS_REENTRANT_RPC
  930. bool "Reentrant RPC support"
  931. depends on UCLIBC_HAS_RPC
  932. default y if !HAVE_SHARED
  933. help
  934. Most packages utilize the normal (non-reentrant) RPC functions, but
  935. some (like exportfs from nfs-utils) need these reentrant versions.
  936. Most people can safely answer N.
  937. config UCLIBC_USE_NETLINK
  938. bool "Use netlink to query interfaces"
  939. default n
  940. depends on UCLIBC_HAS_SOCKET
  941. help
  942. In newer versions of Linux (2.4.17+), support was added for querying
  943. network device information via netlink rather than the old style
  944. ioctl's. Most of the time, the older ioctl style is sufficient (and
  945. it is smaller than netlink), but if you find that not all of your
  946. devices are being returned by the if_nameindex() function, you will
  947. have to use the netlink implementation.
  948. Most people can safely answer N.
  949. config UCLIBC_SUPPORT_AI_ADDRCONFIG
  950. bool "Support the AI_ADDRCONFIG flag"
  951. depends on UCLIBC_USE_NETLINK
  952. default n
  953. help
  954. The implementation of AI_ADDRCONFIG is aligned with the glibc
  955. implementation using netlink to query interfaces to find both
  956. ipv4 and ipv6 support. This is only needed if an application uses
  957. the AI_ADDRCONFIG flag.
  958. Most people can safely answer N.
  959. config UCLIBC_HAS_BSD_RES_CLOSE
  960. bool "Support res_close() (bsd-compat)"
  961. default n
  962. help
  963. Answer Y if you desperately want to support BSD compatibility in
  964. the network code.
  965. Most people will say N.
  966. config UCLIBC_HAS_COMPAT_RES_STATE
  967. bool "Use compatible but bloated _res"
  968. default y
  969. help
  970. Answer Y if you build network utilities and they muck with resolver
  971. internals a lot (_res global structure). uclibc does not use most
  972. of _res.XXX fields, and with this option OFF they won't even exist.
  973. Which will make e.g. dig build fail.
  974. Answering N saves around 400 bytes in bss.
  975. config UCLIBC_HAS_EXTRA_COMPAT_RES_STATE
  976. bool "Use extra compatible but extra bloated _res"
  977. default n
  978. help
  979. Answer Y if selecting UCLIBC_HAS_COMPAT_RES_STATE is not enough.
  980. As far as I can say, this should never be needed.
  981. config UCLIBC_HAS_RESOLV_STUB
  982. bool "Provide libresolv stub"
  983. default n
  984. help
  985. Provide a dummy resolv library.
  986. config UCLIBC_HAS_LIBNSL_STUB
  987. bool "Provide libnsl stub"
  988. default n
  989. help
  990. Provide a dummy nsl library.
  991. endif
  992. menu "String and Stdio Support"
  993. config UCLIBC_HAS_STRING_GENERIC_OPT
  994. bool "Use faster (but larger) generic string functions"
  995. default y
  996. help
  997. Answer Y to use the (tweaked) glibc generic string functions.
  998. In general, they are faster (but 3-5K larger) than the base
  999. uClibc string functions which are optimized solely for size.
  1000. Many people will answer Y.
  1001. config UCLIBC_HAS_STRING_ARCH_OPT
  1002. bool "Use arch-specific assembly string functions (where available)"
  1003. default y
  1004. help
  1005. Answer Y to use any archtecture-specific assembly language string
  1006. functions available for this target plaform.
  1007. Note that assembly implementations are not available for all string
  1008. functions, so some generic (written in C) string functions may
  1009. still be used.
  1010. These are small and fast, the only reason _not_ to say Y here is
  1011. for debugging purposes.
  1012. config UCLIBC_HAS_CTYPE_TABLES
  1013. bool "Use Table Versions Of 'ctype.h' Functions."
  1014. default y
  1015. help
  1016. Answer Y to use table versions of the 'ctype.h' functions.
  1017. While the non-table versions are often smaller when building
  1018. statically linked apps, they work only in stub locale mode.
  1019. Most people will answer Y.
  1020. config UCLIBC_HAS_CTYPE_SIGNED
  1021. bool "Support Signed Characters In 'ctype.h' Functions."
  1022. depends on UCLIBC_HAS_CTYPE_TABLES
  1023. default y
  1024. help
  1025. Answer Y to enable support for passing signed char values to
  1026. the 'ctype.h' functions. ANSI/ISO C99 and SUSv3 specify that
  1027. these functions are only defined for unsigned char values and
  1028. EOF. However, glibc allows negative signed char values as well
  1029. in order to support 'broken old programs'.
  1030. Most people will answer Y.
  1031. choice
  1032. prompt "ctype argument checking"
  1033. depends on UCLIBC_HAS_CTYPE_TABLES
  1034. default UCLIBC_HAS_CTYPE_UNSAFE
  1035. help
  1036. Please select the invalid arg behavior you want for the 'ctype'
  1037. functions.
  1038. The 'ctype' functions are now implemented using table lookups, with
  1039. the arg being the index. This can result in incorrect memory accesses
  1040. or even segfaults for args outside of the allowed range.
  1041. NOTE: This only affects the 'ctype' _functions_. It does not affect
  1042. the macro implementations.
  1043. config UCLIBC_HAS_CTYPE_UNSAFE
  1044. bool "Do not check -- unsafe"
  1045. config UCLIBC_HAS_CTYPE_CHECKED
  1046. bool "Detect and handle appropriately"
  1047. config UCLIBC_HAS_CTYPE_ENFORCED
  1048. bool "Issue a diagnostic and abort()"
  1049. endchoice
  1050. config UCLIBC_HAS_WCHAR
  1051. bool "Wide Character Support"
  1052. default n
  1053. help
  1054. Answer Y to enable wide character support. This will make uClibc
  1055. much larger. It is also currently required for locale support.
  1056. Most people will answer N.
  1057. config UCLIBC_HAS_LOCALE
  1058. bool "Locale Support"
  1059. select UCLIBC_HAS_WCHAR
  1060. select UCLIBC_HAS_CTYPE_TABLES
  1061. default n
  1062. help
  1063. uClibc now has full ANSI/ISO C99 locale support (except for
  1064. wcsftime() and collating items in regex). Be aware that enabling
  1065. this option will make uClibc much larger.
  1066. Enabling UCLIBC_HAS_LOCALE with the default set of supported locales
  1067. (169 UTF-8 locales, and 144 locales for other codesets) will enlarge
  1068. uClibc by around 300k. You can reduce this size by building your own
  1069. custom set of locate data (see extra/locale/LOCALES for details).
  1070. uClibc's locale support is still under development. For example,
  1071. codesets using shift states are not currently supported. Support is
  1072. planned in the next iteration of locale support.
  1073. Answer Y to enable locale support. Most people will answer N.
  1074. choice
  1075. prompt "Locale data"
  1076. depends on UCLIBC_HAS_LOCALE
  1077. default UCLIBC_BUILD_ALL_LOCALE
  1078. config UCLIBC_BUILD_ALL_LOCALE
  1079. bool "All locales"
  1080. depends on UCLIBC_HAS_LOCALE
  1081. help
  1082. This builds all the locales that are available on your
  1083. host-box.
  1084. config UCLIBC_BUILD_MINIMAL_LOCALE
  1085. bool "Only selected locales"
  1086. depends on UCLIBC_HAS_LOCALE
  1087. help
  1088. If you do not need all locales that are available on your
  1089. host-box, then set this to 'Y'.
  1090. config UCLIBC_PREGENERATED_LOCALE_DATA
  1091. bool "Use Pre-generated Locale Data"
  1092. depends on UCLIBC_HAS_LOCALE
  1093. help
  1094. Use pre-built locale data.
  1095. Note that these pregenerated locales are sensitive to your
  1096. target architecture (endianess, bitcount).
  1097. Saying N here is highly recommended.
  1098. endchoice
  1099. config UCLIBC_BUILD_MINIMAL_LOCALES
  1100. string "locales to use"
  1101. depends on UCLIBC_BUILD_MINIMAL_LOCALE
  1102. default "en_US"
  1103. help
  1104. Space separated list of locales to use.
  1105. E.g.:
  1106. en_US en_GB de_AT
  1107. default:
  1108. en_US
  1109. config UCLIBC_DOWNLOAD_PREGENERATED_LOCALE_DATA
  1110. bool "Automagically Download the Pre-generated Locale Data (if necessary)"
  1111. depends on UCLIBC_PREGENERATED_LOCALE_DATA
  1112. default n
  1113. help
  1114. If you would like the build process to use 'wget' to automatically
  1115. download the pregenerated locale data, enable this option. Otherwise
  1116. you will need to obtain the locale data yourself from:
  1117. http://www.uclibc.org/downloads/uClibc-locale-*.tgz
  1118. and place the uClibc-locale-*.tgz tarball in the extra/locale/
  1119. directory.
  1120. Note that the use of pregenerated locale data is discouraged.
  1121. config UCLIBC_HAS_XLOCALE
  1122. bool "Extended Locale Support (experimental/incomplete)"
  1123. depends on UCLIBC_HAS_LOCALE
  1124. default n
  1125. help
  1126. Answer Y to enable extended locale support similar to that provided
  1127. by glibc. This is primarily intended to support libstd++
  1128. functionality.
  1129. However, it also allows thread-specific locale selection via
  1130. uselocale().
  1131. Most people will answer N.
  1132. config UCLIBC_HAS_HEXADECIMAL_FLOATS
  1133. bool "Support hexadecimal float notation"
  1134. depends on UCLIBC_HAS_CTYPE_TABLES
  1135. depends on UCLIBC_HAS_FLOATS
  1136. default n
  1137. help
  1138. Answer Y to enable support for hexadecimal float notation in the
  1139. (wchar and) char string to floating point conversion functions, as
  1140. well as support for the %a and %A conversion specifiers in the
  1141. *printf() and *scanf() functions.
  1142. Most people will answer N.
  1143. config UCLIBC_HAS_GLIBC_DIGIT_GROUPING
  1144. bool "Support glibc's \"'\" flag for allowing locale-specific digit grouping"
  1145. depends on UCLIBC_HAS_LOCALE
  1146. depends on UCLIBC_HAS_FLOATS
  1147. default n
  1148. help
  1149. Answer Y to enable support for glibc's \"'\" flag for allowing
  1150. locale-specific digit grouping in base 10 integer conversions and
  1151. appropriate floating point conversions in the *printf() and *scanf()
  1152. functions.
  1153. Most people will answer N.
  1154. config UCLIBC_HAS_SCANF_LENIENT_DIGIT_GROUPING
  1155. bool "Do not require digit grouping when the \"'\" flag is specified"
  1156. depends on UCLIBC_HAS_GLIBC_DIGIT_GROUPING
  1157. default y
  1158. help
  1159. Answer Y to make digit grouping optional when the \"'\" flag is
  1160. specified.
  1161. This is the standard glibc behavior. If the initial string of digits
  1162. exceeds the maximum group number, the input will be treated as a
  1163. normal non-grouped number.
  1164. Most people will answer N.
  1165. config UCLIBC_HAS_GLIBC_CUSTOM_PRINTF
  1166. bool "Support glibc's register_printf_function() (glibc-compat)"
  1167. depends on !USE_OLD_VFPRINTF
  1168. default n
  1169. help
  1170. Answer Y to support glibc's register_printf_function() to allow an
  1171. application to add its own printf conversion specifiers.
  1172. NOTE: Limits the number or registered specifiers to 10.
  1173. NOTE: Requires new conversion specifiers to be ASCII
  1174. characters (0-0x7f). This is to avoid problems with processing
  1175. format strings in locales with different multibyte conversions.
  1176. Most people will answer N.
  1177. config USE_OLD_VFPRINTF
  1178. bool "Use the old vfprintf implementation"
  1179. depends on !UCLIBC_HAS_WCHAR
  1180. default n
  1181. help
  1182. Set to true to use the old vfprintf instead of the new. This is
  1183. roughly C89 compliant with some extensions, and is much smaller.
  1184. However, it does not support wide chars, positional args, or glibc
  1185. custom printf specifiers.
  1186. Most people will answer N.
  1187. config UCLIBC_PRINTF_SCANF_POSITIONAL_ARGS
  1188. int "Maximum number of positional args. Either 0 or >= 9."
  1189. depends on !USE_OLD_VFPRINTF
  1190. default 9
  1191. help
  1192. Set the maximum number of positional args supported by the
  1193. printf/scanf functions. The Single Unix Specification Version 3
  1194. requires a minimum value of 9. Setting this to a value lower than
  1195. 9 will disable positional arg support and cause the NL_ARGMAX macro
  1196. in limits.h to be #undef'd.
  1197. WARNING! The workspace to support positional args is currently
  1198. allocated on the stack. You probably don't want to set
  1199. this to too high a value.
  1200. Most people will answer 9.
  1201. config UCLIBC_HAS_SCANF_GLIBC_A_FLAG
  1202. bool "Support glibc's 'a' flag for scanf string conversions (not implemented)"
  1203. default n
  1204. help
  1205. NOTE!!! Currently Not Implemented!!! Just A Place Holder!! NOTE!!!
  1206. NOTE!!! Conflicts with an ANSI/ISO C99 scanf flag!! NOTE!!!
  1207. Answer Y to enable support for glibc's 'a' flag for the scanf string
  1208. conversions '%s', '%[', '%ls', '%l[', and '%S'. This is used to
  1209. auto-allocate sufficient memory to hold the data retrieved.
  1210. Most people will answer N.
  1211. choice
  1212. prompt "Stdio buffer size"
  1213. default UCLIBC_HAS_STDIO_BUFSIZ_4096
  1214. help
  1215. Please select a value for BUFSIZ. This will be used by the
  1216. stdio subsystem as the default buffer size for a file, and
  1217. affects fopen(), setvbuf(), etc.
  1218. NOTE: Setting this to 'none' will disable buffering completely.
  1219. However, BUFSIZ will still be defined in stdio.h as 256 because
  1220. many applications use this value.
  1221. config UCLIBC_HAS_STDIO_BUFSIZ_NONE
  1222. bool "none (WARNING - BUFSIZ will be 256 in stdio.h)"
  1223. depends on !UCLIBC_HAS_WCHAR
  1224. config UCLIBC_HAS_STDIO_BUFSIZ_256
  1225. bool "256 (minimum ANSI/ISO C99 value)"
  1226. config UCLIBC_HAS_STDIO_BUFSIZ_512
  1227. bool "512"
  1228. config UCLIBC_HAS_STDIO_BUFSIZ_1024
  1229. bool "1024"
  1230. config UCLIBC_HAS_STDIO_BUFSIZ_2048
  1231. bool "2048"
  1232. config UCLIBC_HAS_STDIO_BUFSIZ_4096
  1233. bool "4096"
  1234. config UCLIBC_HAS_STDIO_BUFSIZ_8192
  1235. bool "8192"
  1236. # If you add more choices, you will need to update uClibc_stdio.h.
  1237. endchoice
  1238. choice
  1239. prompt "Stdio builtin buffer size (uClibc-specific)"
  1240. depends on !UCLIBC_HAS_STDIO_BUFSIZ_NONE
  1241. default UCLIBC_HAS_STDIO_BUILTIN_BUFFER_NONE
  1242. help
  1243. When a FILE is created with fopen(), an attempt is made to allocate
  1244. a BUFSIZ buffer for it. If the allocation fails, fopen() will still
  1245. succeed but the FILE will be unbuffered.
  1246. This option adds a small amount of space to each FILE to act as an
  1247. emergency buffer in the event of a buffer allocation failure.
  1248. Most people will answer None.
  1249. config UCLIBC_HAS_STDIO_BUILTIN_BUFFER_NONE
  1250. bool "None"
  1251. config UCLIBC_HAS_STDIO_BUILTIN_BUFFER_4
  1252. bool "4"
  1253. config UCLIBC_HAS_STDIO_BUILTIN_BUFFER_8
  1254. bool "8"
  1255. # If you add more choices, you will need to update uClibc_stdio.h.
  1256. endchoice
  1257. config UCLIBC_HAS_STDIO_SHUTDOWN_ON_ABORT
  1258. bool "Attempt to shutdown stdio subsystem when abort() is called."
  1259. default n
  1260. help
  1261. ANSI/ISO C99 requires abort() to be asyn-signal-safe. So there was
  1262. a behavioral change made in SUSv3. Previously, abort() was required
  1263. to have the affect of fclose() on all open streams. The wording has
  1264. been changed to "may" from "shall".
  1265. Most people will answer N.
  1266. config UCLIBC_HAS_STDIO_GETC_MACRO
  1267. bool "Provide a macro version of getc()"
  1268. depends on !UCLIBC_HAS_STDIO_BUFSIZ_NONE
  1269. default y
  1270. help
  1271. Provide a macro version of getc().
  1272. Most people will answer Y.
  1273. config UCLIBC_HAS_STDIO_PUTC_MACRO
  1274. bool "Provide a macro version of putc()"
  1275. depends on !UCLIBC_HAS_STDIO_BUFSIZ_NONE
  1276. default y
  1277. help
  1278. Provide a macro version of putc().
  1279. Most people will answer Y.
  1280. config UCLIBC_HAS_STDIO_AUTO_RW_TRANSITION
  1281. bool "Support auto-r/w transition"
  1282. default y
  1283. help
  1284. Answer Y to enable the stdio subsystem to automaticly transition
  1285. between reading and writing. This relaxes the ANSI/ISO C99
  1286. requirement:
  1287. When a file is opened with update mode ('+' as the second or third
  1288. character in the list of mode argument values), both input and output
  1289. may be performed on the associated stream. However, output shall not
  1290. be directly followed by input without an intervening call to the
  1291. fflush function or to a file positioning function (fseek, fsetpos,
  1292. or rewind), and input shall not be directly followed by output without
  1293. an intervening call to a file positioning function, unless the input
  1294. operation encounters end­of­file.
  1295. Most people will answer Y.
  1296. config UCLIBC_HAS_FOPEN_LARGEFILE_MODE
  1297. bool "Support an fopen() 'F' flag for large file mode (uClibc-specific)"
  1298. depends on UCLIBC_HAS_LFS
  1299. default n
  1300. help
  1301. Answer Y to enable a uClibc-specific extension to allow passing an
  1302. additional 'F' flag in the mode string for fopen() to specify that
  1303. the file should be open()ed with the O_LARGEFILE flag set.
  1304. Most people will answer N.
  1305. config UCLIBC_HAS_FOPEN_EXCLUSIVE_MODE
  1306. bool "Support an fopen() 'x' flag for exclusive mode (glibc-compat)"
  1307. default n
  1308. help
  1309. Answer Y to support a glibc extension to allow passing
  1310. additional 'x' flag in the mode string for fopen() to specify that
  1311. the file should be open()ed with the O_EXCL flag set.
  1312. Most people will answer N.
  1313. config UCLIBC_HAS_GLIBC_CUSTOM_STREAMS
  1314. bool "Support fmemopen(), open_memstream(), and fopencookie() (glibc-compat)"
  1315. default n
  1316. help
  1317. Answer Y to support the glibc 'custom stream' extension functions
  1318. fmemopen(), open_memstream(), and fopencookie().
  1319. NOTE: There are some minor differences regarding seeking behavior.
  1320. Most people will answer N.
  1321. config UCLIBC_HAS_PRINTF_M_SPEC
  1322. bool "Support the '%m' specifier in printf format strings (glibc-compat)"
  1323. default n
  1324. help
  1325. Answer Y to support a glibc extension to interpret '%m' in printf
  1326. format strings as an instruction to output the error message string
  1327. (as generated by strerror) corresponding to the current value of
  1328. 'errno'.
  1329. Most people will answer N.
  1330. config UCLIBC_HAS_ERRNO_MESSAGES
  1331. bool "Include the errno message text in the library"
  1332. default y
  1333. help
  1334. Answer Y if you want to include the errno message text in the
  1335. library. This adds about 3K to the library, but enables strerror()
  1336. to generate text other than 'Unknown error <number>'.
  1337. Most people will answer Y.
  1338. config UCLIBC_HAS_SYS_ERRLIST
  1339. bool "Support sys_errlist[] (obsolete-compat)"
  1340. depends on UCLIBC_HAS_ERRNO_MESSAGES
  1341. default n
  1342. help
  1343. Answer Y if you want to support the obsolete sys_errlist[].
  1344. This adds about 0.5k to the library, except for the mips
  1345. arch where it adds over 4K.
  1346. WARNING! In the future, support for sys_errlist[] may be unavailable
  1347. in at least some configurations. In fact, it may be removed
  1348. altogether.
  1349. Most people will answer N.
  1350. Application writers: use the strerror(3) function.
  1351. config UCLIBC_HAS_SIGNUM_MESSAGES
  1352. bool "Include the signum message text in the library"
  1353. default y
  1354. help
  1355. Answer Y if you want to include the signum message text in the
  1356. library. This adds about 0.5K to the library, but enables strsignal()
  1357. to generate text other than 'Unknown signal <number>'.
  1358. Most people will answer Y.
  1359. config UCLIBC_HAS_SYS_SIGLIST
  1360. bool "Support sys_siglist[] (bsd-compat)"
  1361. depends on UCLIBC_HAS_SIGNUM_MESSAGES
  1362. default n
  1363. help
  1364. Answer Y if you want to support sys_siglist[].
  1365. WARNING! In the future, support for sys_siglist[] may be unavailable
  1366. in at least some configurations. In fact, it may be removed
  1367. altogether.
  1368. Most people will answer N.
  1369. config UCLIBC_HAS_GETTEXT_AWARENESS
  1370. bool "Include gettext awareness"
  1371. depends on UCLIBC_HAS_LOCALE && UCLIBC_MJN3_ONLY
  1372. default n
  1373. help
  1374. NOTE!!! Not yet integrated with strerror and strsignal. NOTE!!!
  1375. Answer Y if you want to include weak stub gettext support and
  1376. make the *strerror*() and strsignal() functions gettext-aware.
  1377. Currently, to get functional gettext functionality you will need
  1378. to use gnu gettext.
  1379. Most people will answer N.
  1380. config UCLIBC_HAS_GNU_GETOPT
  1381. bool "Support gnu getopt"
  1382. default y
  1383. help
  1384. Answer Y if you want to include full gnu getopt() instead of a
  1385. (much smaller) SUSv3 compatible getopt().
  1386. Most people will answer Y.
  1387. config UCLIBC_HAS_STDIO_FUTEXES
  1388. bool "Use futexes for multithreaded I/O locking"
  1389. default n
  1390. depends on UCLIBC_HAS_THREADS_NATIVE
  1391. help
  1392. If you want to compile uClibc to use futexes for low-level
  1393. I/O locking, answer Y. Otherwise, answer N.
  1394. config UCLIBC_HAS_GETOPT_LONG
  1395. bool "Support getopt_long/getopt_long_only"
  1396. depends on !UCLIBC_HAS_GNU_GETOPT
  1397. default y
  1398. help
  1399. Answer Y if you want to include getopt_long[_only() used by many
  1400. apps, even busybox.
  1401. Most people will answer Y.
  1402. config UCLIBC_HAS_GNU_GETSUBOPT
  1403. bool "Support glibc getsubopt"
  1404. default y
  1405. help
  1406. Answer Y if you want to include glibc getsubopt() instead of a
  1407. smaller SUSv3 compatible getsubopt().
  1408. Most people will answer Y.
  1409. endmenu
  1410. menu "Big and Tall"
  1411. config UCLIBC_HAS_REGEX
  1412. bool "Regular Expression Support"
  1413. default y
  1414. help
  1415. POSIX regular expression code is really big -- 53k all by itself.
  1416. If you don't use regular expressions, turn this off and save space.
  1417. Of course, if you only statically link, leave this on, since it will
  1418. only be included in your apps if you use regular expressions.
  1419. config UCLIBC_HAS_REGEX_OLD
  1420. bool "Use the older (stable) regular expression code"
  1421. depends on UCLIBC_HAS_REGEX
  1422. default y
  1423. help
  1424. There are two versions of regex. The older (stable) version has
  1425. been in uClibc for quite a long time but hasn't seen too many
  1426. updates. It also has some known issues when dealing with uncommon
  1427. corner cases and multibyte/unicode strings. However, it is quite
  1428. a bit smaller than the newer version.
  1429. If the older version has worked for you and you don't need unicode
  1430. support, then stick with the old version (and say Y here).
  1431. Otherwise, you should use the new version (and say N here).
  1432. config UCLIBC_HAS_FNMATCH
  1433. bool "fnmatch Support"
  1434. default y
  1435. help
  1436. POSIX fnmatch.
  1437. config UCLIBC_HAS_FNMATCH_OLD
  1438. bool "Use the older (stable) fnmatch code"
  1439. depends on UCLIBC_HAS_FNMATCH
  1440. default y
  1441. help
  1442. There are two versions of fnmatch. The older (stable) version has
  1443. been in uClibc for quite a long time but hasn't seen too many
  1444. updates. It also has some known issues when dealing with uncommon
  1445. corner cases and multibyte/unicode strings. However, it is quite
  1446. a bit smaller than the newer version.
  1447. If the older version has worked for you and you don't need unicode
  1448. support, then stick with the old version (and say Y here).
  1449. Otherwise, you should use the new version (and say N here).
  1450. config UCLIBC_HAS_WORDEXP
  1451. bool "Support the wordexp() interface"
  1452. depends on UCLIBC_HAS_GLOB
  1453. default n
  1454. help
  1455. The SuSv3 wordexp() interface performs word expansions per the Shell
  1456. and Utilities volume of IEEE Std 1003.1-2001, Section 2.6. It is
  1457. intended for use by applications that want to implement all of the
  1458. standard Bourne shell expansions on input data.
  1459. This interface is rarely used, and very large. Unless you have a
  1460. pressing need for wordexp(), you should probably answer N.
  1461. config UCLIBC_HAS_NFTW
  1462. bool "Support the nftw() interface"
  1463. default n
  1464. help
  1465. The SuSv3 nftw() interface is used to recursively descend
  1466. directory paths while repeatedly calling a function.
  1467. This interface is rarely used, and adds around 4.5k. Unless you have
  1468. a pressing need for nftw(), you should probably answer N.
  1469. config UCLIBC_HAS_FTW
  1470. bool "Support the ftw() interface"
  1471. default n
  1472. depends on UCLIBC_SUSV4_LEGACY
  1473. help
  1474. The SuSv3 ftw() interface is used to recursively descend
  1475. directory paths while repeatedly calling a function.
  1476. This interface is rarely used, and adds around 4.5k. Unless you have
  1477. a pressing need for ftw(), you should probably answer N.
  1478. config UCLIBC_HAS_GLOB
  1479. bool "Support the glob() interface"
  1480. depends on UCLIBC_HAS_FNMATCH
  1481. default y
  1482. help
  1483. The glob interface is somewhat large (weighing in at about 2,5k). It
  1484. is used fairly often, but is an option since people wanting to go for
  1485. absolute minimum size may wish to omit it.
  1486. Most people will answer Y.
  1487. config UCLIBC_HAS_GNU_GLOB
  1488. bool "Support gnu glob() interface"
  1489. depends on UCLIBC_HAS_GLOB
  1490. default n
  1491. help
  1492. The gnu glob interface is somewhat larger (weighing in at about 4,2k)
  1493. than it's SuSv3 counterpart (and is out of date). It is an old copy
  1494. from glibc and does not support all the GNU specific options.
  1495. Answer Y if you want to include full gnu glob() instead of the smaller
  1496. SUSv3 compatible glob().
  1497. Most people will answer N.
  1498. endmenu
  1499. menu "Library Installation Options"
  1500. config SHARED_LIB_LOADER_PREFIX
  1501. string "Shared library loader path"
  1502. depends on HAVE_SHARED
  1503. default "$(RUNTIME_PREFIX)lib"
  1504. help
  1505. When using shared libraries, this path is the location where the
  1506. shared library will be invoked. This value will be compiled into
  1507. every binary compiled with uClibc.
  1508. For a typical target system this should be set to "/lib", such that
  1509. 'make install' will install /lib/ld-uClibc.so.0.
  1510. BIG FAT WARNING:
  1511. If you do not have a shared library loader with the correct name
  1512. sitting in the directory this points to, your binaries will not
  1513. run.
  1514. config RUNTIME_PREFIX
  1515. string "uClibc runtime library directory"
  1516. default "/usr/$(TARGET_ARCH)-linux-uclibc/"
  1517. help
  1518. RUNTIME_PREFIX is the directory into which the uClibc runtime
  1519. libraries will be installed. The result will look something
  1520. like the following:
  1521. $(RUNTIME_PREFIX)/
  1522. lib/ <contains all runtime libraries>
  1523. usr/bin/ldd <the ldd utility program>
  1524. sbin/ldconfig <the ldconfig utility program>
  1525. This value is used by the 'make install' Makefile target. Since this
  1526. directory is compiled into the shared library loader, you will need to
  1527. recompile uClibc if you change this value...
  1528. For a typical target system this should be set to "/", such that
  1529. 'make install' will install /lib/libuClibc-<VERSION>.so
  1530. config DEVEL_PREFIX
  1531. string "uClibc development environment directory"
  1532. default "/usr/$(TARGET_ARCH)-linux-uclibc/usr/"
  1533. help
  1534. DEVEL_PREFIX is the directory into which the uClibc development
  1535. environment will be installed. The result will look something
  1536. like the following:
  1537. $(DEVEL_PREFIX)/
  1538. lib/ <contains static libs>
  1539. include/ <Where all the header files go>
  1540. This value is used by the 'make install' Makefile target when
  1541. installing a uClibc development environment.
  1542. For a typical target system this should be set to "/usr", such that
  1543. 'make install' will install /usr/include/<header files>.
  1544. config HARDWIRED_ABSPATH
  1545. bool "Hardwire absolute paths into linker scripts"
  1546. default y
  1547. help
  1548. This prepends absolute paths to the libraries mentioned in linker
  1549. scripts such as libc.so.
  1550. This is a build time optimization. It has no impact on dynamic
  1551. linking at runtime, which doesn't use linker scripts.
  1552. You must disable this to use uClibc with a relocatable toolchain,
  1553. such as the prebuilt binary cross compilers at
  1554. http://uclibc.org/downloads/binaries which may be installed at an
  1555. arbitrary location (such as in a user's home directory).
  1556. The amount of time saved by this optimization is actually too small to
  1557. measure. The linker just had to search the library path to find the
  1558. linker script, so the dentries are cache hot if it has to search the
  1559. same path again. But it's what glibc does, so we do it too.
  1560. endmenu
  1561. menu "Security options"
  1562. config UCLIBC_BUILD_PIE
  1563. bool "Build utilities as ET_DYN/PIE executables"
  1564. depends on HAVE_SHARED
  1565. depends on TARGET_arm || TARGET_frv || TARGET_i386 || TARGET_mips || TARGET_powerpc
  1566. select FORCE_SHAREABLE_TEXT_SEGMENTS
  1567. default n
  1568. help
  1569. If you answer Y here, ldd and iconv are built as ET_DYN/PIE
  1570. executables.
  1571. It requires gcc-3.4 and binutils-2.15 (for arm 2.16) or later.
  1572. More about ET_DYN/PIE binaries on <http://pax.grsecurity.net/> .
  1573. WARNING: This option also enables FORCE_SHAREABLE_TEXT_SEGMENTS, so
  1574. all libraries have to be built with -fPIC or -fpic, and all
  1575. assembler functions must be written as position independent
  1576. code (PIC).
  1577. config UCLIBC_HAS_ARC4RANDOM
  1578. bool "Include the arc4random() function"
  1579. default n
  1580. help
  1581. Answer Y to support the OpenBSD-like arc4random() function. This
  1582. function picks a random number between 0 and N, and will always return
  1583. something even if the random driver is dead. If urandom fails then
  1584. gettimeofday(2) will be used as the random seed. This function is
  1585. designed to be more dependable than invoking /dev/urandom directly.
  1586. OpenSSL and OpenNTPD currently support this function.
  1587. Most people will answer N.
  1588. config HAVE_NO_SSP
  1589. bool
  1590. default n
  1591. config UCLIBC_HAS_SSP
  1592. bool "Support for GCC stack smashing protector"
  1593. depends on !HAVE_NO_SSP
  1594. default n
  1595. help
  1596. Add code to support GCC's -fstack-protector[-all] option to uClibc.
  1597. This requires GCC 4.1 or newer. GCC does not have to provide libssp,
  1598. the needed functions are added to ldso/libc instead.
  1599. GCC's stack protector is a reimplementation of IBM's propolice.
  1600. See http://www.trl.ibm.com/projects/security/ssp/ and
  1601. http://www.linuxfromscratch.org/hints/downloads/files/ssp.txt
  1602. for details.
  1603. Note that NOEXECSTACK on a kernel with address space randomization
  1604. is generally sufficient to prevent most buffer overflow exploits
  1605. without increasing code size. This option essentially adds debugging
  1606. code to catch them.
  1607. Most people will answer N.
  1608. config UCLIBC_HAS_SSP_COMPAT
  1609. bool "Support for gcc-3.x propolice smashing stack protector"
  1610. depends on UCLIBC_HAS_SSP
  1611. default n
  1612. help
  1613. Add gcc-3.x propolice smashing stack protector to the library.
  1614. This requires a patched version of GCC, supporting the
  1615. -fstack-protector[-all] options, with the __guard and
  1616. __stack_smash_handler functions removed from libgcc.
  1617. These functions are added to ldso/libc instead.
  1618. More information at:
  1619. <http://www.research.ibm.com/trl/projects/security/ssp/>
  1620. Most people will answer N.
  1621. config SSP_QUICK_CANARY
  1622. bool "Use simple guard values without accessing /dev/urandom"
  1623. depends on UCLIBC_HAS_SSP
  1624. default n
  1625. help
  1626. Use gettimeofday(2) to define the __guard without accessing
  1627. /dev/urandom.
  1628. WARNING: This makes smashing stack protector vulnerable to timing
  1629. attacks.
  1630. Most people will answer N.
  1631. choice
  1632. prompt "Propolice protection blocking signal"
  1633. depends on UCLIBC_HAS_SSP
  1634. default PROPOLICE_BLOCK_ABRT if ! DODEBUG
  1635. default PROPOLICE_BLOCK_SEGV if DODEBUG
  1636. help
  1637. "abort" use SIGABRT to block offending programs.
  1638. This is the default implementation.
  1639. "segfault" use SIGSEGV to block offending programs.
  1640. Use this for debugging.
  1641. If unsure, answer "abort".
  1642. config PROPOLICE_BLOCK_ABRT
  1643. bool "abort"
  1644. config PROPOLICE_BLOCK_SEGV
  1645. bool "segfault"
  1646. endchoice
  1647. config UCLIBC_BUILD_SSP
  1648. bool "Build uClibc with -fstack-protector"
  1649. depends on UCLIBC_HAS_SSP
  1650. default n
  1651. help
  1652. Build all uClibc libraries and executables with -fstack-protector,
  1653. adding extra stack overflow checking to most uClibc functions.
  1654. config UCLIBC_BUILD_RELRO
  1655. bool "Build uClibc with linker option -z RELRO"
  1656. depends on HAVE_SHARED
  1657. default y
  1658. help
  1659. Build all libraries and executables with "ld -z relro".
  1660. This tells the linker to mark chunks of an executable or shared
  1661. library read-only after applying dynamic relocations. (This comes
  1662. up when a global const variable is initialized to the address of a
  1663. function or the value of another global variable.)
  1664. This is a fairly obscure option the ld man page doesn't even bother
  1665. to document properly. It's a security paranoia issue that's more
  1666. likely to consume memory (by allocating an extra page) rather than
  1667. save it.
  1668. This is explained in more depth at
  1669. http://www.airs.com/blog/archives/189
  1670. Nobody is likely to care whether you say Y or N here.
  1671. config UCLIBC_BUILD_NOW
  1672. bool "Build uClibc with linker option -z NOW"
  1673. depends on HAVE_SHARED
  1674. default n
  1675. help
  1676. Build all libraries and executables with "ld -z now".
  1677. This tells the linker to resolve all symbols when the library is
  1678. first loaded, rather than when each function is first called. This
  1679. increases start-up latency by a few microseconds and may do
  1680. unnecessary work (resolving symbols that are never used), but the
  1681. realtime people like it for making microbenchmark timings slightly
  1682. more predictable and in some cases it can be slightly faster due to
  1683. CPU cache behavior (not having to fault the linker back in to do
  1684. lazy symbol resolution).
  1685. Most people can't tell the difference between selecting Y or N here.
  1686. config UCLIBC_BUILD_NOEXECSTACK
  1687. bool "Build uClibc with noexecstack marking"
  1688. default y
  1689. help
  1690. Mark all assembler files as noexecstack, which will mark uClibc
  1691. as not requiring an executable stack. (This doesn't prevent other
  1692. files you link against from claiming to need an executable stack, it
  1693. just won't cause uClibc to request it unnecessarily.)
  1694. This is a security thing to make buffer overflows harder to exploit.
  1695. By itself, it's kind of useless, as Linus Torvalds explained in 1998:
  1696. http://old.lwn.net/1998/0806/a/linus-noexec.html
  1697. It only actually provides any security when combined with address
  1698. space randomization, explained here: http://lwn.net/Articles/121845/
  1699. Address space randomization is on by default in current linux
  1700. kernels (although it can be disabled using the option
  1701. CONFIG_COMPAT_BRK).
  1702. You should probably say Y.
  1703. endmenu
  1704. menu "uClibc development/debugging options"
  1705. config CROSS_COMPILER_PREFIX
  1706. string "Cross-compiling toolchain prefix"
  1707. default ""
  1708. help
  1709. The prefix used to execute your cross-compiling toolchain. For
  1710. example, if you run 'arm-linux-uclibc-gcc' to compile something,
  1711. then enter 'arm-linux-uclibc-' here.
  1712. config UCLIBC_EXTRA_CFLAGS
  1713. string "Enter any extra CFLAGS to use to build uClibc"
  1714. default ""
  1715. help
  1716. Add any additional CFLAGS to be used to build uClibc.
  1717. config DODEBUG
  1718. bool "Build uClibc with debugging symbols"
  1719. default n
  1720. select EXTRA_WARNINGS
  1721. help
  1722. Say Y here if you wish to compile uClibc with debugging symbols.
  1723. This will allow you to use a debugger to examine uClibc internals
  1724. while applications are running. This increases the size of the
  1725. library considerably and should only be used when doing development.
  1726. If you are doing development and want to debug uClibc, answer Y.
  1727. Otherwise, answer N.
  1728. config DODEBUG_PT
  1729. bool "Build pthread with debugging output"
  1730. depends on UCLIBC_HAS_THREADS && LINUXTHREADS_OLD
  1731. default n
  1732. help
  1733. Enable debug output in libpthread. This is only useful when doing
  1734. development in libpthread itself.
  1735. Otherwise, answer N.
  1736. config DOSTRIP
  1737. bool "Strip libraries and executables"
  1738. default y
  1739. depends on !DODEBUG
  1740. help
  1741. Say Y here if you do wish to strip all uClibc libraries and
  1742. executables. No stripping increases the size of the binaries
  1743. considerably, but makes it possible to debug uClibc libraries.
  1744. Most people will answer Y.
  1745. config DOASSERTS
  1746. bool "Build uClibc with run-time assertion testing"
  1747. default n
  1748. help
  1749. Say Y here to include runtime assertion tests.
  1750. This enables runtime assertion testing in some code, which can
  1751. increase the size of the library and incur runtime overhead.
  1752. If you say N, then this testing will be disabled.
  1753. config SUPPORT_LD_DEBUG
  1754. bool "Build the shared library loader with debugging support"
  1755. depends on HAVE_SHARED
  1756. default n
  1757. help
  1758. Answer Y here to enable all the extra code needed to debug the uClibc
  1759. native shared library loader. The level of debugging noise that is
  1760. generated depends on the LD_DEBUG environment variable... Just set
  1761. LD_DEBUG to something like: 'LD_DEBUG=token1,token2,.. prog' to
  1762. debug your application. Diagnostic messages will then be printed to
  1763. the stderr.
  1764. For now these debugging tokens are available:
  1765. detail provide more information for some options
  1766. move display copy processing
  1767. symbols display symbol table processing
  1768. reloc display relocation processing; detail shows the
  1769. relocation patch
  1770. nofixups never fixes up jump relocations
  1771. bindings displays the resolve processing (function calls);
  1772. detail shows the relocation patch
  1773. all Enable everything!
  1774. The additional environment variable:
  1775. LD_DEBUG_OUTPUT=file
  1776. redirects the diagnostics to an output file created using
  1777. the specified name and the process id as a suffix.
  1778. An excellent start is simply:
  1779. $ LD_DEBUG=binding,move,symbols,reloc,detail ./appname
  1780. or to log everything to a file named 'logfile', try this
  1781. $ LD_DEBUG=all LD_DEBUG_OUTPUT=logfile ./appname
  1782. If you are doing development and want to debug uClibc's shared library
  1783. loader, answer Y. Mere mortals answer N.
  1784. config SUPPORT_LD_DEBUG_EARLY
  1785. bool "Build the shared library loader with early debugging support"
  1786. depends on HAVE_SHARED
  1787. default n
  1788. help
  1789. Answer Y here to if you find the uClibc shared library loader is
  1790. crashing or otherwise not working very early on. This is typical
  1791. only when starting a new port when you haven't figured out how to
  1792. properly get the values for argc, argv, environ, etc. This method
  1793. allows a degree of visibility into the very early shared library
  1794. loader initialization process. If you are doing development and want
  1795. to debug the uClibc shared library loader early initialization,
  1796. answer Y. Mere mortals answer N.
  1797. config UCLIBC_MALLOC_DEBUGGING
  1798. bool "Build malloc with debugging support"
  1799. depends on MALLOC || MALLOC_STANDARD
  1800. default n
  1801. help
  1802. Answer Y here to compile extra debugging support code into malloc.
  1803. Malloc debugging output may then be enabled at runtime using the
  1804. MALLOC_DEBUG environment variable.
  1805. The value of MALLOC_DEBUG should be an integer, which is interpreted
  1806. as a bitmask with the following bits:
  1807. 1 - do extra consistency checking
  1808. 2 - output messages for malloc/free calls and OS
  1809. allocation calls
  1810. 4 - output messages for the `MMB' layer
  1811. 8 - output messages for internal malloc heap manipulation
  1812. calls
  1813. Because this increases the size of malloc appreciably (due to strings
  1814. etc), you should say N unless you need to debug a malloc problem.
  1815. config WARNINGS
  1816. string "Compiler Warnings"
  1817. default "-Wall"
  1818. help
  1819. Set this to the set of gcc warnings you wish to see while compiling.
  1820. config EXTRA_WARNINGS
  1821. bool "Enable extra annoying warnings"
  1822. default n
  1823. help
  1824. If you wish to build with extra warnings enabled, say Y here.
  1825. config DOMULTI
  1826. bool "Compile all sources at once into an object"
  1827. default n
  1828. help
  1829. Set this to compile all sources at once into an object (IMA).
  1830. This mode of compilation uses alot of memory but may produce
  1831. smaller binaries.
  1832. Note that you need a very recent GCC for this to work, like
  1833. gcc >= 4.3 plus eventually some patches.
  1834. If unsure, keep the default of N.
  1835. config UCLIBC_MJN3_ONLY
  1836. bool "Manuel's hidden warnings"
  1837. default n
  1838. help
  1839. Answer Y here to see all Manuel's personal notes, warnings, and todos.
  1840. Most people will answer N.
  1841. endmenu