diff -ruN gc-8.2.2.orig/configure.ac gc-8.2.2/configure.ac
--- gc-8.2.2.orig/configure.ac	2022-08-26 20:44:49.000000000 +0200
+++ gc-8.2.2/configure.ac	2023-01-17 10:24:04.342866823 +0100
@@ -833,13 +833,15 @@
 AS_IF([test "$THREADS" = posix],
   [AC_MSG_CHECKING(for pthread_setname_np)
    old_CFLAGS="$CFLAGS"
-   CFLAGS="$CFLAGS $CFLAGS_EXTRA -Werror"
-   AC_TRY_COMPILE([#include <pthread.h>],
+   CFLAGS="$CFLAGS $CFLAGS_EXTRA -Werror -pthread"
+   AC_TRY_COMPILE([#define _GNU_SOURCE
+                  #include <pthread.h>],
                   [pthread_setname_np("thread-name")],
      [AC_MSG_RESULT([yes (w/o tid)])
       AC_DEFINE([HAVE_PTHREAD_SETNAME_NP_WITHOUT_TID], [1],
                 [Define to use 'pthread_setname_np(const char*)' function.])],
-     [AC_TRY_COMPILE([#include <pthread.h>],
+     [AC_TRY_COMPILE([#define _GNU_SOURCE
+                     #include <pthread.h>],
                      [pthread_setname_np(pthread_self(), "thread-name-%u", 0)],
        [AC_MSG_RESULT([yes (with tid and arg)])
         AC_DEFINE([HAVE_PTHREAD_SETNAME_NP_WITH_TID_AND_ARG], [1],