This fixes the errors as following.
ERROR: ./lib/libfann.so contains undefined symbols:
13: 0000000000000000 0 NOTYPE GLOBAL DEFAULT UND exp
14: 0000000000000000 0 NOTYPE GLOBAL DEFAULT UND sin
15: 0000000000000000 0 NOTYPE GLOBAL DEFAULT UND cos
22: 0000000000000000 0 NOTYPE GLOBAL DEFAULT UND pow
31: 0000000000000000 0 NOTYPE GLOBAL DEFAULT UND log