glibc

• http://www.gnu.org/software/libc/

• License: LGPL

• C library from the GNU project

• Designed for performance, standards compliance and portability

• Found on all GNU / Linux host systems

• Of course, actively maintained

• Quite big for small embedded systems: about 1.7 MB on arm ( Familiar Linux: libc: 1.2 MB, libm: 500 KB)