diff -ru iperf-3.17.1.orig/src/iperf_api.h iperf-3.17.1/src/iperf_api.h

--- iperf-3.17.1.orig/src/iperf_api.h	2024-05-13 20:40:55.000000000 +0200

+++ iperf-3.17.1/src/iperf_api.h	2024-07-02 20:05:03.818580250 +0200

@@ -44,7 +44,7 @@

 #include <stdatomic.h>

 #else

 #warning "No <stdatomic.h> available"

-typedef u_int64_t atomic_uint_fast64_t;

+typedef uint64_t atomic_uint_fast64_t;

 #endif // HAVE_STDATOMIC_H

 struct iperf_test;

diff -ru iperf-3.17.1.orig/src/main.c iperf-3.17.1/src/main.c

--- iperf-3.17.1.orig/src/main.c	2024-05-13 20:40:55.000000000 +0200

+++ iperf-3.17.1/src/main.c	2024-07-02 20:04:06.908582670 +0200

@@ -65,15 +65,6 @@

      * know how to check this on GCC. GCC on CentOS 7 / RHEL 7 is the

      * targeted use case for these check.

      */

-#ifndef HAVE_STDATOMIC_H

-#ifdef __GNUC__

-    if (! __atomic_always_lock_free (sizeof (u_int64_t), 0)) {

-#endif // __GNUC__

-        fprintf(stderr, "Warning: Cannot guarantee lock-free operation with 64-bit data types\n");

-#ifdef __GNUC__

-    }

-#endif // __GNUC__

-#endif // HAVE_STDATOMIC_H

     // XXX: Setting the process affinity requires root on most systems.

     //      Is this a feature we really need?

Only in iperf-3.17.1/src: main.c.orig