Note: Keep the 2.41 symbol until we rebuild packages against the 2.42
symbol.

Index: glibc-upstream/sysdeps/htl/pt-once.c
===================================================================
--- glibc-upstream.orig/sysdeps/htl/pt-once.c
+++ glibc-upstream/sysdeps/htl/pt-once.c
@@ -58,5 +58,8 @@ libc_hidden_def (__pthread_once)
 versioned_symbol (libc, __pthread_once, pthread_once, GLIBC_2_42);
 
 #if OTHER_SHLIB_COMPAT (libpthread, GLIBC_2_12, GLIBC_2_42)
+compat_symbol (libpthread, __pthread_once, pthread_once, GLIBC_2_41);
+#endif
+#if OTHER_SHLIB_COMPAT (libpthread, GLIBC_2_12, GLIBC_2_42)
 compat_symbol (libpthread, __pthread_once, pthread_once, GLIBC_2_12);
 #endif
Index: glibc-upstream/sysdeps/mach/hurd/i386/libc.abilist
===================================================================
--- glibc-upstream.orig/sysdeps/mach/hurd/i386/libc.abilist
+++ glibc-upstream/sysdeps/mach/hurd/i386/libc.abilist
@@ -2588,6 +2588,7 @@ GLIBC_2.41 pthread_mutexattr_setpshared
 GLIBC_2.41 pthread_mutexattr_setrobust F
 GLIBC_2.41 pthread_mutexattr_setrobust_np F
 GLIBC_2.41 pthread_mutexattr_settype F
+GLIBC_2.41 pthread_once F
 GLIBC_2.41 pthread_sigmask F
 GLIBC_2.42 __inet_ntop_chk F
 GLIBC_2.42 __inet_pton_chk F
Index: glibc-upstream/sysdeps/mach/hurd/x86_64/libc.abilist
===================================================================
--- glibc-upstream.orig/sysdeps/mach/hurd/x86_64/libc.abilist
+++ glibc-upstream/sysdeps/mach/hurd/x86_64/libc.abilist
@@ -2271,6 +2271,7 @@ GLIBC_2.41 pthread_mutexattr_setpshared
 GLIBC_2.41 pthread_mutexattr_setrobust F
 GLIBC_2.41 pthread_mutexattr_setrobust_np F
 GLIBC_2.41 pthread_mutexattr_settype F
+GLIBC_2.41 pthread_once F
 GLIBC_2.41 pthread_sigmask F
 GLIBC_2.42 __inet_ntop_chk F
 GLIBC_2.42 __inet_pton_chk F
Index: glibc-upstream/htl/Versions
===================================================================
--- glibc-upstream.orig/htl/Versions
+++ glibc-upstream/htl/Versions
@@ -148,6 +148,7 @@ libc {
     pthread_mutexattr_setpshared;
     pthread_mutexattr_setrobust; pthread_mutexattr_setrobust_np;
     pthread_mutexattr_settype;
+    pthread_once;
     pthread_sigmask;
   }