/in/foo.cc: In function 'int main()':
/in/foo.cc:7:2: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
  gets(s);
  ^~~~
In file included from /in/foo.cc:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
/in/foo.cc:7:8: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
  gets(s);
        ^
In file included from /in/foo.cc:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
/in/foo.cc:9:2: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
  for( len=0; s[len]!='\0'; len++);
  ^~~
/in/foo.cc:10:3: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'for'
   for(i=len; i>=0; i--)
   ^~~
/tmp/cc3oh9u0.o: In function `main':
foo.cc:(.text.startup+0x19): warning: the `gets' function is dangerous and should not be used.