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newport_j
August 1st, 2012, 08:27 PM
I installed Ubuntu 11.10 as a virtual machine on Centos. Ubuntu is the guest and Centos 6.3 is the host.

I tried some basic compile commands and it kept giving me the error message:

undefined reference to 'log10'

undefined reference to 'sqrt'

It obviously was not linking to the math libary during compile and link the stage. However, I was using the -lm command correctly and I discovered the when I entered

echo $LD_LIBRARY_PATH

gave me nothing, so I must reinitialize my LD_LIBRARY_PATH to avoid the errors shown above.

I am not sure what library holds log10 and sqrt math functions. I believe that they are in the same library, I am just not sure which one.

Also, since I compile for 32 and 64 bit applications, I am sure the 32 and 64 bit libaraies are not the same. So my LD_LIBARY_PATH must accomodate both.

Exactly, what libararies are needed? Can I run some command line comand and just build the LD_LIBRARY_PATH?

Thanks in advance.

Newport_j

alexpage
September 11th, 2012, 02:09 PM
Are you sure this wasn't the problem?: http://stackoverflow.com/questions/7824439/c-math-linker-problems-on-ubuntu-11-10