--- a/atomic/unix/mutex64.c	2023/02/09 12:45:02	1907540

+++ b/atomic/unix/mutex64.c	2023/02/09 13:36:18	1907541

@@ -96,7 +96,26 @@

 APR_DECLARE(apr_uint64_t) apr_atomic_read64(volatile apr_uint64_t *mem)

 {

+    /* On 32bit CPUs this loads with two instructions (tearing),

+     * so a lock is needed to ensure atomicity.

+     *

+     * APR_SIZEOF_VOIDP is probably not the right check for 32 vs 64 bits CPUs

+     * but it spares an (hardly-)exhaustive list of supported CPUs (and using

+     * assembly). If APR_SIZEOF_VOIDP==4 means that the compiler generates

+     * 32bit instructions (-m32 or whatever) then it's the right check though.

+     */

+#if APR_SIZEOF_VOIDP >= 8

     return *mem;

+#else

+    apr_uint64_t cur_value;

+    DECLARE_MUTEX_LOCKED(mutex, mem);

+

+    cur_value = *mem;

+

+    MUTEX_UNLOCK(mutex);

+

+    return cur_value;

+#endif

 }

 APR_DECLARE(void) apr_atomic_set64(volatile apr_uint64_t *mem, apr_uint64_t val)