diff --git a/stdlib/test-bz22786.c b/stdlib/test-bz22786.c
index 777bf91..bb1e04f 100644
--- a/stdlib/test-bz22786.c
+++ b/stdlib/test-bz22786.c
@@ -26,6 +26,7 @@
 #include <unistd.h>
 #include <sys/stat.h>
 #include <sys/types.h>
+#include <support/blob_repeat.h>
 #include <support/check.h>
 #include <support/support.h>
 #include <support/temp_file.h>
@@ -39,17 +40,12 @@ do_test (void)
   const char *lnk = xasprintf ("%s/symlink", dir);
   const size_t path_len = (size_t) INT_MAX + strlen (lnk) + 1;
 
-  DIAG_PUSH_NEEDS_COMMENT;
-#if __GNUC_PREREQ (7, 0)
-  /* GCC 7 warns about too-large allocations; here we need such
-     allocation to succeed for the test to work.  */
-  DIAG_IGNORE_NEEDS_COMMENT (7, "-Walloc-size-larger-than=");
-#endif
-  char *path = malloc (path_len);
-  DIAG_POP_NEEDS_COMMENT;
+  struct support_blob_repeat repeat
+    = support_blob_repeat_allocate ("a", 1, path_len);
+  char *path = repeat.start;
   if (path == NULL)
     {
-      printf ("malloc (%zu): %m\n", path_len);
+      printf ("Repeated allocation (%zu bytes): %m\n", path_len);
       /* On 31-bit s390 the malloc will always fail as we do not have
 	 so much memory, and we want to mark the test unsupported.
 	 Likewise on systems with little physical memory the test will
@@ -62,7 +58,6 @@ do_test (void)
   /* Construct very long path = "/tmp/bz22786.XXXX/symlink/aaaa....."  */
   char *p = mempcpy (path, lnk, strlen (lnk));
   *(p++) = '/';
-  memset (p, 'a', path_len - (p - path) - 2);
   p[path_len - (p - path) - 1] = '\0';
 
   /* This call crashes before the fix for bz22786 on 32-bit platforms.  */
@@ -76,6 +71,7 @@ do_test (void)
 
   /* Cleanup.  */
   unlink (lnk);
+  support_blob_repeat_free (&repeat);
 
   return 0;
 }