CodeRunner: math - pow

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math - pow - unknown

Hi,

I am experiencing a strange issue with a C program question.

Even though I include <math.h> in the Answer, I get the following error message:

/tmp/ccLd97P7.o: In function `binToDez':
__tester__.c:(.text+0x1cc): undefined reference to `pow'
collect2: error: ld returned 1 exit status

The question is attached in moodle format.

Any ideas?

Thank you,

Jens

This error message comes from the linker. The gnu linker doesn't search the math library by default - you need to customise the question, or edit its prototype, and add the "-lm" link argument. See https://coderunner.org.nz/mod/forum/discuss.php?d=172

I agree it seems a bit pathetic that you should have to do that, but it is the standard default Linux C behaviour. However, I'll update the built-in C and C++ question types to include the -lm link option in the next release. You'll still need to specify appropriate link options for other libraries, however.