Building a project with Yagarto tool chain, receive linker erros, error list below:
c:/program files/yagarto/bin/../lib/gcc/arm-elf/4.4.1/../../../../arm-elf/lib\li
bg.a(lib_a-mallocr.o): In function `malloc_extend_top':
C:\msys\1.0\home\yagarto\newlib-build\arm-elf\newlib\libc\stdlib/../../../../../
newlib-1.17.0/newlib/libc/stdlib/mallocr.c:2160: undefined reference to `_sbrk_r
'
C:\msys\1.0\home\yagarto\newlib-build\arm-elf\newlib\libc\stdlib/../../../../../
newlib-1.17.0/newlib/libc/stdlib/mallocr.c:2197: undefined reference to `_sbrk_r
'
c:/program files/yagarto/bin/../lib/gcc/arm-elf/4.4.1/../../../../arm-elf/lib\li
bg.a(lib_a-freer.o): In function `_malloc_trim_r':
C:\msys\1.0\home\yagarto\newlib-build\arm-elf\newlib\libc\stdlib/../../../../../
newlib-1.17.0/newlib/libc/stdlib/mallocr.c:3326: undefined reference to `_sbrk_r
'
C:\msys\1.0\home\yagarto\newlib-build\arm-elf\newlib\libc\stdlib/../../../../../
newlib-1.17.0/newlib/libc/stdlib/mallocr.c:3335: undefined reference to `_sbrk_r
'
C:\msys\1.0\home\yagarto\newlib-build\arm-elf\newlib\libc\stdlib/../../../../../
newlib-1.17.0/newlib/libc/stdlib/mallocr.c:3340: undefined reference to `_sbrk_r
'
c:/program files/yagarto/bin/../lib/gcc/arm-elf/4.4.1/../../../../arm-elf/lib\li
bg.a(lib_a-makebuf.o): In function `__smakebuf_r':
C:\msys\1.0\home\yagarto\newlib-build\arm-elf\newlib\libc\stdio/../../../../../n
ewlib-1.17.0/newlib/libc/stdio/makebuf.c:59: undefined reference to `_fstat_r'
C:\msys\1.0\home\yagarto\newlib-build\arm-elf\newlib\libc\stdio/../../../../../n
ewlib-1.17.0/newlib/libc/stdio/makebuf.c:110: undefined reference to `_isatty_r'

c:/program files/yagarto/bin/../lib/gcc/arm-elf/4.4.1/../../../../arm-elf/lib\li
bg.a(lib_a-stdio.o): In function `__sclose':
C:\msys\1.0\home\yagarto\newlib-build\arm-elf\newlib\libc\stdio/../../../../../n
ewlib-1.17.0/newlib/libc/stdio/stdio.c:124: undefined reference to `_close_r'
c:/program files/yagarto/bin/../lib/gcc/arm-elf/4.4.1/../../../../arm-elf/lib\li
bg.a(lib_a-stdio.o): In function `__sseek':
C:\msys\1.0\home\yagarto\newlib-build\arm-elf\newlib\libc\stdio/../../../../../n
ewlib-1.17.0/newlib/libc/stdio/stdio.c:106: undefined reference to `_lseek_r'
c:/program files/yagarto/bin/../lib/gcc/arm-elf/4.4.1/../../../../arm-elf/lib\li
bg.a(lib_a-stdio.o): In function `__swrite':
C:\msys\1.0\home\yagarto\newlib-build\arm-elf\newlib\libc\stdio/../../../../../n
ewlib-1.17.0/newlib/libc/stdio/stdio.c:78: undefined reference to `_lseek_r'
C:\msys\1.0\home\yagarto\newlib-build\arm-elf\newlib\libc\stdio/../../../../../n
ewlib-1.17.0/newlib/libc/stdio/stdio.c:86: undefined reference to `_write_r'
c:/program files/yagarto/bin/../lib/gcc/arm-elf/4.4.1/../../../../arm-elf/lib\li
bg.a(lib_a-stdio.o): In function `__sread':
C:\msys\1.0\home\yagarto\newlib-build\arm-elf\newlib\libc\stdio/../../../../../n
ewlib-1.17.0/newlib/libc/stdio/stdio.c:48: undefined reference to `_read_r'
collect2: ld returned 1 exit status
make: *** [flash] Error 1