commit ee7c2451a102b4cd3c87a31b3156ad4458729840
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Wed May 19 16:48:19 2021 +0100

    Suppress -Wcast-qual warnings in bsearch
    
    The first cast to (void *) is redundant but should be (const void *)
    anyway, because that's the type of the lvalue being assigned to.
    
    The second cast is necessary and intentionally not const-correct, so
    tell the compiler not to warn about it.

diff --git a/bits/stdlib-bsearch.h b/bits/stdlib-bsearch.h
index 4132dc6af0..d688ed2e15 100644
--- a/bits/stdlib-bsearch.h
+++ b/bits/stdlib-bsearch.h
@@ -29,14 +29,21 @@ bsearch (const void *__key, const void *__base, size_t __nmemb, size_t __size,
   while (__l < __u)
     {
       __idx = (__l + __u) / 2;
-      __p = (void *) (((const char *) __base) + (__idx * __size));
+      __p = (const void *) (((const char *) __base) + (__idx * __size));
       __comparison = (*__compar) (__key, __p);
       if (__comparison < 0)
 	__u = __idx;
       else if (__comparison > 0)
 	__l = __idx + 1;
       else
+#if __GNUC_PREREQ(4, 6)
+# pragma GCC diagnostic push
+# pragma GCC diagnostic ignored "-Wcast-qual"
+#endif
 	return (void *) __p;
+#if __GNUC_PREREQ(4, 6)
+# pragma GCC diagnostic pop
+#endif
     }
 
   return NULL;