Undefined reference to sqrt()

Question

I include the <math.h> but the code still not recognising basic operations such as sqrt or pow. https://code.sololearn.com/cEBuyGQdCrHL/?ref=app

Answer 1

First of all, don't be frustrated and congratulation as you've just discovered a bug in SoloLearn!

After a quick check I believe it's a linker problem of the C online compiler used by SoloLearn.

You may report this behaviour to [e-mail] and meanwhile you may try to run your code at other cloud compilers available like:-

https://www.onlinegdb.com

P/S: I've verified with link above and it works! 😉

Answer 2

Hi Zephyr Koo ,
It's been a long time!
Been busy with work I guess?

This is really intriguing case, because I could get the code to run (Yes in Code Playground) when I pass a literal value as argument for `sqrt`

printf("sqrt(361) = %.0lf", sqrt(361)); // this works, strangely

At first I thought the problem was with the format specifier "%d\n" at line 10, but nope, I was wrong. It still doesn't work although I changed it to "%d" only.

Tried to change some numbers by adding decimal point, and occasional casting, but it didn't work either.

s = s + 1.0 / (double)(i*i); // didn't help

pi = sqrt(6.0 * s); // didn't help

Looking forward for others' opinions : )

Answer 3

Chum4k3r Wow indeed thanks for informing! It's probably the weirdest bug I've seen in SoloLearn. 👍

Answer 4

Guillermo Alonso
Zephyr Koo
Ace

I found these on SO, seems it be a compiler issue (gcc if I understand it correctly). No experience with compiler command options so I'm leaving this to you guys 👍

[Referenced from the thread below]
https://stackoverflow.com/questions/5248919/undefined-reference-to-sqrt-or-other-mathematical-functions

[Marked as duplicate (forwarded to one above)]
https://stackoverflow.com/questions/10409032/why-am-i-getting-undefined-reference-to-sqrt-error-even-though-i-include-math

Answer 5

Ipang Yup it has been awhile and feel grateful to be able to come back from time to time!

You've got some good observation and I really wonder the strange behaviour as well. Nice catch! 😉

Answer 6

I was facing this issue in my code yesterday, but today it worked. Seems like the linker bug has been fixed

Answer 7

Good to have you back Zephyr Koo 👍