Use newer APIs for ruby head/4.1 support

[rwstauner]

The deprecated ones have been removed from ruby as of 2026-04-12
ruby/ruby@b66b500

This resolves a compilation error with ruby head:

rbtrace.c:1160:37: error: incompatible function pointer types passing 'VALUE (VALUE, VALUE)' (aka 'unsigned long (unsigned long, unsigned long)') to parameter of
      type 'rb_block_call_func_t' (aka 'unsigned long (*)(unsigned long, unsigned long, int, const unsigned long *, unsigned long)') [-Wincompatible-function-pointer-types]
 1160 |   signal_handler_proc = rb_proc_new(signal_handler_wrapper, Qnil);
      |                                     ^~~~~~~~~~~~~~~~~~~~~~

[rwstauner]

@SamSaffron I would appreciate a review if you have time to look at this fix for newer ruby versions. Thanks!

[SamSaffron]

I follow, the challenge I have here is that I am not mega familiar with all the new APIs so I am stuck trusting my robot testing skills :)

feedback from robot analysis:

• rbtrace -h is failing, not your fault, but we should clean up. Do you mind fixing? (missing a require 'objspace') - also oddly we are missing a test for this

• looks like 4.1 are removing ObjectSpace._id2ref which we lean on, we should clean that up. Perhaps something along the lines of:

diff --git a/ext/rbtrace.c b/ext/rbtrace.c
index 9bc259a..1e5c6c8 100644
--- a/ext/rbtrace.c
+++ b/ext/rbtrace.c
@@ -491,8 +491,9 @@ event_hook(rb_event_t event, NODE *node, VALUE self, ID mid, VALUE klass)
             val = rb_inspect(rb_ivar_get(self, rb_intern(expr)));
 
           } else {
-            snprintf(buffer, len+150, "(begin; ObjectSpace._id2ref(%ld).instance_eval{ %s }; rescue Exception => e; e; end).inspect", NUM2LONG(rb_obj_id(self)), expr);
-            val = rb_eval_string_protect(buffer, 0);
+            snprintf(buffer, len+150, "proc { |__rbtrace_receiver__| (begin; __rbtrace_receiver__.instance_eval { %s }; rescue Exception => e; e; end).inspect }", expr);
+            VALUE expr_proc = rb_eval_string_protect(buffer, 0);
+            val = rb_funcall(expr_proc, rb_intern("call"), 1, self);
           }
 
           if (RTEST(val) && TYPE(val) == T_STRING) {
diff --git a/server.rb b/server.rb
index 20b5314..05806fc 100644
--- a/server.rb
+++ b/server.rb
@@ -32,6 +32,7 @@ while true
         Dir.pwd
         Process.pid
         'hello'.multiply_vowels(3){ :ohai }
+        'hello'.upcase
         sleep rand*0.5
 
         ENV['blah']
diff --git a/test.sh b/test.sh
index bd735d7..ccedf51 100755
--- a/test.sh
+++ b/test.sh
@@ -51,11 +51,34 @@ assert_trace() {
   echo
 }
 
+assert_timed_trace() {
+  expected="$1"
+  shift
+  output=$(mktemp)
+
+  echo ------------------------------------------
+  echo ./bin/rbtrace -p $PID "$@"
+  echo ------------------------------------------
+  bundle exec ./bin/rbtrace -p $PID "$@" >"$output" 2>&1 &
+  tracer_pid=$!
+  sleep 2
+  kill "$tracer_pid" 2>/dev/null || true
+  wait "$tracer_pid" 2>/dev/null || true
+  cat "$output"
+  if ! grep -F "$expected" "$output" >/dev/null; then
+    rm -f "$output"
+    return 1
+  fi
+  rm -f "$output"
+  echo
+}
+
 trace -m Test.run --devmode
 trace -m sleep
 trace -m sleep Dir.chdir Dir.pwd Process.pid "String#gsub" "String#*"
 trace -m "Kernel#"
 trace -m "String#gsub(self,@test)" "String#*(self,__source__)" "String#multiply_vowels(self,self.length,num)"
+assert_timed_trace 'String#upcase(self.class=String)' -m 'String#upcase(self.class)'
 assert_trace '=> 2' -e 'p(1 + 1)'
 trace -h
 trace --gc --slow=200

• CI is not testing on head, do you mind adding to the CI checks so we keep it honest

[rwstauner]

Awesome, thank you @SamSaffron!

• added tests for --heapdump and --shapesdump to ensure objspace is loaded.
• used your proc replacement idea for id2ref
• added head to CI

[SamSaffron]

Looks good ... will cut a new version!

[rwstauner]

Thank you!

[SamSaffron]

Thanks Randy, if there are any other changes you feel we need happy to add them in.