Don't try to use the new code path on legacy rubies

Author: ivoanjo

ext/datadog_profiling_native_extension/collectors_thread_context.c

@@ -1,5 +1,6 @@
 #include <ruby.h>
 
+#include "datadog_ruby_common.h"
 #include "collectors_thread_context.h"
 #include "clock_id.h"
 #include "collectors_stack.h"
@@ -1688,35 +1689,41 @@ static VALUE _native_sample_skipped_allocation_samples(DDTRACE_UNUSED VALUE self
   return Qtrue;
 }
 
-static VALUE otel_context_storage_for(thread_context_collector_state *state, VALUE thread) {
-  if (state->otel_context_source == OTEL_CONTEXT_SOURCE_FIBER_IVAR) { // otel-api 1.5+
-    VALUE current_fiber = current_fiber_for(thread);
-    return current_fiber == Qnil ? Qnil : rb_ivar_get(current_fiber, otel_fiber_context_storage_id /* @opentelemetry_context */);
-  }
-
-  if (state->otel_context_source == OTEL_CONTEXT_SOURCE_FIBER_LOCAL) { // otel-api < 1.5
-    return rb_thread_local_aref(thread, otel_context_storage_id /* __opentelemetry_context_storage__ */);
-  }
+#ifndef NO_CURRENT_FIBER_FOR // Ruby 3.1+
+  static VALUE otel_context_storage_for(thread_context_collector_state *state, VALUE thread) {
+    if (state->otel_context_source == OTEL_CONTEXT_SOURCE_FIBER_IVAR) { // otel-api 1.5+
+      VALUE current_fiber = current_fiber_for(thread);
+      return current_fiber == Qnil ? Qnil : rb_ivar_get(current_fiber, otel_fiber_context_storage_id /* @opentelemetry_context */);
+    }
 
-  // If we got here, it means we never observed a context being set. Let's probe which one to use.
-  VALUE current_fiber = current_fiber_for(thread);
-  if (current_fiber != Qnil) {
-    VALUE context_storage = rb_ivar_get(current_fiber, otel_fiber_context_storage_id /* @opentelemetry_context */);
-    if (context_storage != Qnil) {
-      state->otel_context_source = OTEL_CONTEXT_SOURCE_FIBER_IVAR; // Remember for next time
-      return context_storage;
+    if (state->otel_context_source == OTEL_CONTEXT_SOURCE_FIBER_LOCAL) { // otel-api < 1.5
+      return rb_thread_local_aref(thread, otel_context_storage_id /* __opentelemetry_context_storage__ */);
     }
-  } else {
-    VALUE context_storage = rb_thread_local_aref(thread, otel_context_storage_id /* __opentelemetry_context_storage__ */);
-    if (context_storage != Qnil) {
-      state->otel_context_source = OTEL_CONTEXT_SOURCE_FIBER_LOCAL; // Remember for next time
-      return context_storage;
+
+    // If we got here, it means we never observed a context being set. Let's probe which one to use.
+    VALUE current_fiber = current_fiber_for(thread);
+    if (current_fiber != Qnil) {
+      VALUE context_storage = rb_ivar_get(current_fiber, otel_fiber_context_storage_id /* @opentelemetry_context */);
+      if (context_storage != Qnil) {
+        state->otel_context_source = OTEL_CONTEXT_SOURCE_FIBER_IVAR; // Remember for next time
+        return context_storage;
+      }
+    } else {
+      VALUE context_storage = rb_thread_local_aref(thread, otel_context_storage_id /* __opentelemetry_context_storage__ */);
+      if (context_storage != Qnil) {
+        state->otel_context_source = OTEL_CONTEXT_SOURCE_FIBER_LOCAL; // Remember for next time
+        return context_storage;
+      }
     }
-  }
 
-  // There's no context storage attached to the current thread
-  return Qnil;
-}
+    // There's no context storage attached to the current thread
+    return Qnil;
+  }
+#else
+  static inline VALUE otel_context_storage_for(DDTRACE_UNUSED thread_context_collector_state *state, VALUE thread) {
+    return rb_thread_local_aref(thread, otel_context_storage_id /* __opentelemetry_context_storage__ */);
+  }
+#endif
 
 // This method differs from trace_identifiers_for/ddtrace_otel_trace_identifiers_for to support the situation where
 // the opentelemetry ruby library is being used for tracing AND the ddtrace tracing bits are not involved at all.

ext/datadog_profiling_native_extension/gvl_profiling_helper.c

@@ -1,5 +1,7 @@
 #include <ruby.h>
 #include <ruby/thread.h>
+
+#include "datadog_ruby_common.h"
 #include "gvl_profiling_helper.h"
 
 #if !defined(NO_GVL_INSTRUMENTATION) && !defined(USE_GVL_PROFILING_3_2_WORKAROUNDS) // Ruby 3.3+

ext/datadog_profiling_native_extension/gvl_profiling_helper.h

@@ -39,14 +39,6 @@
 
   static inline void gvl_profiling_init(void) { }
 
-  // This header gets included in private_vm_access.c which can't include datadog_ruby_common.h so we replicate this
-  // helper here
-  #ifdef __GNUC__
-    #define DDTRACE_UNUSED  __attribute__((unused))
-  #else
-    #define DDTRACE_UNUSED
-  #endif
-
   // NOTE: This is a hack that relies on the knowledge that on Ruby 3.2 the
   // RUBY_INTERNAL_THREAD_EVENT_READY and RUBY_INTERNAL_THREAD_EVENT_RESUMED events always get called on the thread they
   // are about. Thus, we can use our thread local storage hack to get this data, even though the event doesn't include it.

ext/datadog_profiling_native_extension/private_vm_api_access.c

@@ -40,6 +40,13 @@
   #endif
 #endif
 
+// This file can't include datadog_ruby_common.h so we replicate this here
+#ifdef __GNUC__
+  #define DDTRACE_UNUSED  __attribute__((unused))
+#else
+  #define DDTRACE_UNUSED
+#endif
+
 #define PRIVATE_VM_API_ACCESS_SKIP_RUBY_INCLUDES
 #include "private_vm_api_access.h"
 
@@ -847,6 +854,8 @@ bool is_raised_flag_set(VALUE thread) { return thread_struct_from_object(thread)
     if (expected_current_fiber != actual_current_fiber) rb_raise(rb_eRuntimeError, "current_fiber_for() self-test failed");
   }
 #else
-  VALUE current_fiber_for(VALUE thread) { rb_raise(rb_eRuntimeError, "Not implemented for Ruby < 3.1"); }
+  NORETURN(VALUE current_fiber_for(DDTRACE_UNUSED VALUE thread));
+
+  VALUE current_fiber_for(DDTRACE_UNUSED VALUE thread) { rb_raise(rb_eRuntimeError, "Not implemented for Ruby < 3.1"); }
   void self_test_current_fiber_for(void) { } // Nothing to do
 #endif