diff -ru a/libsanitizer/sanitizer_common/sanitizer_common_interceptors_ioctl.inc b/libsanitizer/sanitizer_common/sanitizer_common_interceptors_ioctl.inc
--- a/libsanitizer/sanitizer_common/sanitizer_common_interceptors_ioctl.inc	2014-09-23 17:59:53.000000000 +0000
+++ b/libsanitizer/sanitizer_common/sanitizer_common_interceptors_ioctl.inc	2021-10-30 19:48:38.690007561 +0000
@@ -358,15 +358,6 @@
 
 #if SANITIZER_LINUX && !SANITIZER_ANDROID
   // _(SIOCDEVPLIP, WRITE, struct_ifreq_sz); // the same as EQL_ENSLAVE
-  _(CYGETDEFTHRESH, WRITE, sizeof(int));
-  _(CYGETDEFTIMEOUT, WRITE, sizeof(int));
-  _(CYGETMON, WRITE, struct_cyclades_monitor_sz);
-  _(CYGETTHRESH, WRITE, sizeof(int));
-  _(CYGETTIMEOUT, WRITE, sizeof(int));
-  _(CYSETDEFTHRESH, NONE, 0);
-  _(CYSETDEFTIMEOUT, NONE, 0);
-  _(CYSETTHRESH, NONE, 0);
-  _(CYSETTIMEOUT, NONE, 0);
   _(EQL_EMANCIPATE, WRITE, struct_ifreq_sz);
   _(EQL_ENSLAVE, WRITE, struct_ifreq_sz);
   _(EQL_GETMASTRCFG, WRITE, struct_ifreq_sz);
diff -ru a/libsanitizer/sanitizer_common/sanitizer_platform_limits_posix.cc b/libsanitizer/sanitizer_common/sanitizer_platform_limits_posix.cc
--- a/libsanitizer/sanitizer_common/sanitizer_platform_limits_posix.cc	2021-10-30 19:40:51.805824323 +0000
+++ b/libsanitizer/sanitizer_common/sanitizer_platform_limits_posix.cc	2021-10-30 19:51:13.640403192 +0000
@@ -143,7 +143,6 @@
 #include <sys/statvfs.h>
 #include <sys/timex.h>
 #include <sys/user.h>
-#include <linux/cyclades.h>
 #include <linux/if_eql.h>
 #include <linux/if_plip.h>
 #include <linux/lp.h>
@@ -392,7 +391,6 @@
 
 #if SANITIZER_LINUX && !SANITIZER_ANDROID
   unsigned struct_ax25_parms_struct_sz = sizeof(struct ax25_parms_struct);
-  unsigned struct_cyclades_monitor_sz = sizeof(struct cyclades_monitor);
 #if EV_VERSION > (0x010000)
   unsigned struct_input_keymap_entry_sz = sizeof(struct input_keymap_entry);
 #else
@@ -759,15 +757,6 @@
 #endif  // SANITIZER_LINUX || SANITIZER_FREEBSD
 
 #if SANITIZER_LINUX && !SANITIZER_ANDROID
-  unsigned IOCTL_CYGETDEFTHRESH = CYGETDEFTHRESH;
-  unsigned IOCTL_CYGETDEFTIMEOUT = CYGETDEFTIMEOUT;
-  unsigned IOCTL_CYGETMON = CYGETMON;
-  unsigned IOCTL_CYGETTHRESH = CYGETTHRESH;
-  unsigned IOCTL_CYGETTIMEOUT = CYGETTIMEOUT;
-  unsigned IOCTL_CYSETDEFTHRESH = CYSETDEFTHRESH;
-  unsigned IOCTL_CYSETDEFTIMEOUT = CYSETDEFTIMEOUT;
-  unsigned IOCTL_CYSETTHRESH = CYSETTHRESH;
-  unsigned IOCTL_CYSETTIMEOUT = CYSETTIMEOUT;
   unsigned IOCTL_EQL_EMANCIPATE = EQL_EMANCIPATE;
   unsigned IOCTL_EQL_ENSLAVE = EQL_ENSLAVE;
   unsigned IOCTL_EQL_GETMASTRCFG = EQL_GETMASTRCFG;
diff -ru a/libsanitizer/sanitizer_common/sanitizer_platform_limits_posix.h b/libsanitizer/sanitizer_common/sanitizer_platform_limits_posix.h
--- a/libsanitizer/sanitizer_common/sanitizer_platform_limits_posix.h	2021-10-30 19:40:51.698824053 +0000
+++ b/libsanitizer/sanitizer_common/sanitizer_platform_limits_posix.h	2021-10-30 19:51:39.680469814 +0000
@@ -875,7 +875,6 @@
 
 #if SANITIZER_LINUX && !SANITIZER_ANDROID
   extern unsigned struct_ax25_parms_struct_sz;
-  extern unsigned struct_cyclades_monitor_sz;
   extern unsigned struct_input_keymap_entry_sz;
   extern unsigned struct_ipx_config_data_sz;
   extern unsigned struct_kbdiacrs_sz;
@@ -1220,15 +1219,6 @@
 #endif  // SANITIZER_LINUX || SANITIZER_FREEBSD
 
 #if SANITIZER_LINUX && !SANITIZER_ANDROID
-  extern unsigned IOCTL_CYGETDEFTHRESH;
-  extern unsigned IOCTL_CYGETDEFTIMEOUT;
-  extern unsigned IOCTL_CYGETMON;
-  extern unsigned IOCTL_CYGETTHRESH;
-  extern unsigned IOCTL_CYGETTIMEOUT;
-  extern unsigned IOCTL_CYSETDEFTHRESH;
-  extern unsigned IOCTL_CYSETDEFTIMEOUT;
-  extern unsigned IOCTL_CYSETTHRESH;
-  extern unsigned IOCTL_CYSETTIMEOUT;
   extern unsigned IOCTL_EQL_EMANCIPATE;
   extern unsigned IOCTL_EQL_ENSLAVE;
   extern unsigned IOCTL_EQL_GETMASTRCFG;