Fix undefined behaviour. * lib/bitrotate.h (rotl16, rotr16, rotl8, rotr8): Case x to 'unsigned int', to avoid shift operations on 'int'. * lib/xmemdup0.c (xmemdup0): Don't invoke memcpy with a zero size. * tests/test-count-leading-zeros.c (main): Use a random number that has as many bits as TYPE, not only 2*15 or 2*31 bits. * tests/test-count-trailing-zeros.c (main): Likewise. * tests/test-count-one-bits.c (main): Likewise. * tests/test-memmem.c: Don't include "null-ptr.h". (main): Use zerosize_ptr() instead of null_ptr(). * modules/memmem-tests (Files): Remove tests/null-ptr.h.

--- a/tests/test-memmem.c	Sat Mar 09 00:27:19 2019 +0100
+++ b/tests/test-memmem.c	Sat Mar 09 20:32:25 2019 +0100
@@ -26,7 +26,6 @@
 #include <stdlib.h>
 #include <unistd.h>
 
-#include "null-ptr.h"
 #include "zerosize-ptr.h"
 #include "macros.h"
 
@@ -81,7 +80,7 @@
 
   {
     const char input[] = "foo";
-    const char *result = memmem (input, strlen (input), null_ptr (), 0);
+    const char *result = memmem (input, strlen (input), zerosize_ptr (), 0);
     ASSERT (result == input);
   }