ls: fix segfault-if-standalone-shell, add big fat comment.

archival/libunarchive/get_header_ar.c

@@ -66,9 +66,9 @@ char get_header_ar(archive_handle_t *archive_handle)
 
 	/* long filenames have '/' as the first character */
 	if (ar.formatted.name[0] == '/') {
+#if ENABLE_FEATURE_AR_LONG_FILENAMES
 		unsigned long_offset;
 
-#if ENABLE_FEATURE_AR_LONG_FILENAMES
 		if (ar.formatted.name[1] == '/') {
 			/* If the second char is a '/' then this entries data section
 			 * stores long filename for multiple entries, they are stored

coreutils/ls.c

@@ -777,6 +777,9 @@ static const unsigned opt_flags[] = {
 };
 
 
+/* THIS IS A "SAFE" APPLET, main() MAY BE CALLED INTERNALLY FROM SHELL */
+/* BE CAREFUL! */
+
 int ls_main(int argc, char **argv);
 int ls_main(int argc, char **argv)
 {
@@ -797,8 +800,6 @@ int ls_main(int argc, char **argv)
 	USE_FEATURE_AUTOWIDTH(char *terminal_width_str = NULL;)
 	USE_FEATURE_LS_COLOR(char *color_opt;)
 
-	setvbuf(stdout, bb_common_bufsiz1, _IOFBF, BUFSIZ);
-
 #if ENABLE_FEATURE_LS_TIMESTAMPS
 	time(&current_time_t);
 #endif