This is causing a regression with coredumps of all gtk-demos and majority
of the integrated tests

core 'core' of 4134:    gtk4-demo
------------  lwp# 1 / thread# 1  ---------------
 00007fc35911a7b6 gtk_css_node_invalidate () + 26
 00007fc35911a8ef gtk_css_node_do_ensure_style () + 7f
 00007fc35911adb6 gtk_css_node_validate_internal () + c6
 00007fc35911ae17 gtk_css_node_validate_internal () + 127
 00007fc35911ae17 gtk_css_node_validate_internal () + 127
 00007fc35911ae17 gtk_css_node_validate_internal () + 127
 00007fc35911ae17 gtk_css_node_validate_internal () + 127
 00007fc35911cbe2 gtk_css_node_validate () + 62
 00007fc3590d9052 gtk_window_show () + 32
 00007fc3584397a0 _g_closure_invoke_va () + d0
 00007fc358459ebf g_signal_emit_valist () + f6f
 00007fc35845a3dd g_signal_emit () + 7d
 00007fc3590babf9 gtk_widget_show () + 129
 00007fc35a2447f8 command_line () + 218
 00007fc35814f1a3 _g_cclosure_marshal_INT__OBJECT () + 53
 00007fc3584395a5 g_closure_invoke () + c5
 00007fc35844eda6 ???????? ()
 00007fc358459688 g_signal_emit_valist () + 738
 00007fc35845a3dd g_signal_emit () + 7d
 00007fc3581ad453 g_application_call_command_line () + a3
 00007fc3581af7f1 g_application_real_local_command_line () + 221
 00007fc3581af933 g_application_run () + f3
 00007fc35a2449d4 main () + 1a4
 00007fc35a2174b3 _start () + 43

--- gtk-4.16.6/meson.build.orig
+++ gtk-4.16.6/meson.build
@@ -225,17 +225,6 @@
   endif
 endforeach
 
-# We use links() because sigsetjmp() is often a macro hidden behind other macros
-cdata.set('HAVE_SIGSETJMP',
-  cc.links('''#define _POSIX_SOURCE
-              #include <setjmp.h>
-              int main (void) {
-                sigjmp_buf env;
-                sigsetjmp (env, 0);
-                return 0;
-              }''', name: 'sigsetjmp'),
-)
-
 # Check for __uint128_t (gcc) by checking for 128-bit division
 uint128_t_src = '''int main() {
 static __uint128_t v1 = 100;