Hide declaration of gets(3) for C11 and later.

gets(3) was removed from C11.

Change-Id: I4040a8a6c6d5d2a86878e8a80ca67964fbbb82a8
diff --git a/libc/include/stdio.h b/libc/include/stdio.h
index 62acb3a..6110932 100644
--- a/libc/include/stdio.h
+++ b/libc/include/stdio.h
@@ -254,7 +254,9 @@
 int vdprintf(int, const char * __restrict, __va_list) __printflike(2, 0);
 
 #ifndef __AUDIT__
+#if defined(__STDC_VERSION__) && __STDC_VERSION__ < 201112L
 char* gets(char*) __warnattr("gets is very unsafe; consider using fgets");
+#endif
 int sprintf(char* __restrict, const char* __restrict, ...)
     __printflike(2, 3) __warnattr("sprintf is often misused; please use snprintf");
 char* tmpnam(char*) __warnattr("tmpnam possibly used unsafely; consider using mkstemp");
diff --git a/libstdc++/include/cstdio b/libstdc++/include/cstdio
index 3c8b5c6..25838ad 100644
--- a/libstdc++/include/cstdio
+++ b/libstdc++/include/cstdio
@@ -63,7 +63,9 @@
 using ::fwrite;
 using ::getc;
 using ::getchar;
+#if defined(__STDC_VERSION__) && __STDC_VERSION__ < 201112L
 using ::gets;
+#endif
 using ::perror;
 using ::printf;
 using ::putc;