gcc link error (looking for log, floor function)

ufmale · 07-19-2008, 12:05 AM

I got an error trying to link object files.
It is looking for different math function

gcc a.o b.o c.o -o myapp

undefined reference to `log'
undefined reference to `floor'
undefined reference to `cos'
undefined reference to `pow'

Is there any linker flag i need to build my app? COmpiling seems to work fine.
I am building it on fedora 7.

komodo · 07-19-2008, 12:52 AM

It looks as though you have no reference to math.h in your code. can you show us your preprocessor directives? If there is no reference to math.h, your calls to math functions like floor, pow, etc will not be swallowed by the linker. The compiler doesn't care about these things, it is the linker that makes the most problems.

hariram_eee · 07-19-2008, 01:21 AM

Try math.h else give a compiler option as -lmath

ufmale · 07-19-2008, 09:21 AM

Found the problem. it is -lm