Error while building Minetest

minetest_error

$ make -j2

[  1%] Built target jthread
[ 17%] Built target lua
[ 50%] Built target minetestserver
Linking CXX executable ../bin/minetest
/usr/bin/ld: /usr/lib/gcc/x86_64-unknown-linux-gnu/4.7.2/../../../../lib/libcurl.a(libcurl_la-timeval.o): undefined reference to symbol 'clock_gettime@@GLIBC_2.2.5'
/usr/bin/ld: note: 'clock_gettime@@GLIBC_2.2.5' is defined in DSO /usr/lib/librt.so.1 so try adding it to the linker command line
/usr/lib/librt.so.1: could not read symbols: Invalid operation
collect2: error: ld returned 1 exit status
make[2]: *** [bin/minetest] Error 1
make[1]: *** [src/CMakeFiles/minetest.dir/all] Error 2
make: *** [all] Error 2