util.c: Add comment.

I wonder if we need to worry about compatibility with a 1994 libc?

diff --git a/util.c b/util.c
index 9d4b246..6dc39f0 100644 (file)
--- a/util.c
+++ b/util.c
@@ -521,7 +521,8 @@ Perl_instr(const char *big, const char *little)
 
     PERL_ARGS_ASSERT_INSTR;
 
-    /* libc prior to 4.6.27 did not work properly on a NULL 'little' */
+    /* libc prior to 4.6.27 (late 1994) did not work properly on a NULL
+     * 'little' */
     if (!little)
        return (char*)big;
     return strstr((char*)big, (char*)little);