The new standard passed its final draft review on October 10, 2011 and was officially ratified by ISO and published as ISO/IEC 9899:2011 on December 8, 2011, with no comments requiring resolution by participating national bodies.
[12] Programs can use predefined macros to determine whether an implementation supports a certain feature or not.
The optional bounds-checking interfaces (Annex K) remain controversial and have not been widely implemented, and their deprecation or removal from the next standard revision has been proposed.
[21] In addition, Annex K does not include the more useful TR24731-2 (dynamic allocation functions), such as vasprintf and open_memstream.
[22] The few open-source implementations include Open Watcom C/C++'s "Safer C" library[23] and safeclib.