View Compilation Error

0_0_26967842_25516.cpp: In function 'int main()':
0_0_26967842_25516.cpp:7:55: error: 'memset' was not declared in this scope
 #define CLR(NAME,VALUE) memset(NAME,VALUE,sizeof(NAME))
                                                       ^
0_0_26967842_25516.cpp:29:4: note: in expansion of macro 'CLR'
    CLR(c,0);
    ^