Undefined reference to log10 function

Question

I am building using Eclipse Kepler, and have included math.h. However, I am getting an error

'undefined reference to log10'.

Also types uint8_t and unit32_t are not being resolved. I have included both stdint.h and inttypes.h, just to be sure, but wasn't successful. Can someone kindly help?

Solution

'undefined reference to log10'.

Because, the header file only provides the forward declaration of the function. The actual function definition is present in the ("math") library. You need to link with the math library using -lm.

Reference: man page for log10

Also, AFAIK, uint<N>_t are present in <stdint.h>. Please check for the existence for the header file itself and/or any typos (like unit32_t in your example) in your code.

Comments

[Martin James]

'undefined', rather than 'unresolved' sounds like a compiler error, rather than linker?