Using GNU Cross Compiler Tools, on MacBook Pro (Intel host).
arm-elf-gcc toolsuite with newlib downloaded from:
http://www.mikrocontroller.net/articles/ARM_GCC_toolchain_for_Linux_and_Mac_OS_X

I am having trouble with adding math functions (like sin using "math.h"
and using -lm in my linker with this toolset.

I am new to newlib and am not sure if i need to download an include
directory with this toolchain, or if I just need to link against -lm

I seem to get the following errors:

JimMacBookPro:~/Desktop/umon/umon_apps/user_manual jamessclarkiv$ make
clean
rm -f *.o app[1-5] app[1-5].dis app[1-5].sym symtbl
JimMacBookPro:~/Desktop/umon/umon_apps/user_manual jamessclarkiv$ make
app2
arm-elf-gcc -fno-builtin -mcpu=arm9tdmi -c -Wall -O -g -I. -o crt0_arm.o
crt0_arm.S
arm-elf-gcc -fno-builtin -mcpu=arm9tdmi -c -Wall -O -g -I. -D
MONCOMPTR=0x10000020 -o main2.o main2.c
main2.c: In function 'main':
main2.c:24: warning: assignment from incompatible pointer type
main2.c:28: warning: implicit declaration of function 'sin'
arm-elf-gcc -fno-builtin -mcpu=arm9tdmi -c -Wall -O -g -I. -o monlib.o
monlib.c
monlib.c: In function 'mon_xcrc16':
monlib.c:733: warning: pointer targets in passing argument 1 of
'_xcrc16' differ in signedness
arm-elf-ld -e start -o app2 -Ttext 0x20100000 crt0_arm.o main2.o
monlib.o /usr/local/arm/lib/gcc/arm-elf/4.1.0/libgcc.a
/usr/local/arm/arm-elf/lib/libm.a
/usr/local/arm/arm-elf/lib/libm.a(s_sin.o): In function `sin':
../../../.././newlib/libm/math/s_sin.c:117: undefined reference to
`__subdf3'
/usr/local/arm/arm-elf/lib/libm.a(e_rem_pio2.o): In function
`__ieee754_rem_pio2':
../../../.././newlib/libm/math/e_rem_pio2.c:166: undefined reference to
`__subdf3'
../../../.././newlib/libm/math/e_rem_pio2.c:104: undefined reference to
`__subdf3'
../../../.././newlib/libm/math/e_rem_pio2.c:106: undefined reference to
`__subdf3'
../../../.././newlib/libm/math/e_rem_pio2.c:107: undefined reference to
`__subdf3'
/usr/local/arm/arm-elf/lib/libm.a(e_rem_pio2.o):../../../.././newlib/lib 
m/math/e_rem_pio2.c:107:
more undefined references to `__subdf3' follow
/usr/local/arm/arm-elf/lib/libm.a(e_rem_pio2.o): In function
`__ieee754_rem_pio2':
../../../.././newlib/libm/math/e_rem_pio2.c:129: undefined reference to
`__muldf3'
../../../.././newlib/libm/math/e_rem_pio2.c:129: undefined reference to
`__adddf3'
../../../.././newlib/libm/math/e_rem_pio2.c:129: undefined reference to
`__fixdfsi'
../../../.././newlib/libm/math/e_rem_pio2.c:130: undefined reference to
`__floatsidf'
../../../.././newlib/libm/math/e_rem_pio2.c:131: undefined reference to
`__muldf3'

etc.

Only change to the working makefile above was linking against libm.a and
libgcc.a and adding a single sin() call to my main() and including
<math.h> in main.

The ../../../.././newlib etc directories do not seem to exist on my
system??

Thanks in advance for any help.

Best regards,
Jim Clark