/in/foo.cc: In function 'int main()':
/in/foo.cc:72:9: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
         gets(str);
         ^~~~
In file included from /usr/include/c++/6/cstdio:42:0,
                 from /usr/include/c++/6/ext/string_conversions.h:43,
                 from /usr/include/c++/6/bits/basic_string.h:5417,
                 from /usr/include/c++/6/string:52,
                 from /usr/include/c++/6/stdexcept:39,
                 from /usr/include/c++/6/array:39,
                 from /usr/include/c++/6/tuple:39,
                 from /usr/include/c++/6/bits/stl_map.h:63,
                 from /usr/include/c++/6/map:61,
                 from /in/foo.cc:9:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
/in/foo.cc:72:17: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
         gets(str);
                 ^
In file included from /usr/include/c++/6/cstdio:42:0,
                 from /usr/include/c++/6/ext/string_conversions.h:43,
                 from /usr/include/c++/6/bits/basic_string.h:5417,
                 from /usr/include/c++/6/string:52,
                 from /usr/include/c++/6/stdexcept:39,
                 from /usr/include/c++/6/array:39,
                 from /usr/include/c++/6/tuple:39,
                 from /usr/include/c++/6/bits/stl_map.h:63,
                 from /usr/include/c++/6/map:61,
                 from /in/foo.cc:9:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
/tmp/ccqogYMz.o: In function `main':
foo.cc:(.text.startup+0x81): warning: the `gets' function is dangerous and should not be used.