diff --git a/vm_exec.h b/vm_exec.h
index 34d3403453..7480a807da 100644
--- a/vm_exec.h
+++ b/vm_exec.h
@@ -11,6 +11,8 @@
 
 **********************************************************************/
 
+#include "ruby/internal/has/attribute.h"
+
 typedef long OFFSET;
 typedef unsigned long lindex_t;
 typedef VALUE GENTRY;
@@ -60,18 +62,20 @@ error !
 /************************************************/
 #elif OPT_TAILCALL_THREADED_CODE
 
-/* Same as __attribute__((musttail)), but slightly wider support (GCC 15) */
-#define MUSTTAIL [[clang::musttail]]
+#if !RBIMPL_HAS_ATTRIBUTE(musttail)
+#error support for musttail attribute is required for tailcall threading
+#endif
+
+/* Declares that the function call MUST be tailcall optimized */
+#define MUSTTAIL __attribute__((musttail))
 
 #define LABEL(x)  insn_func_##x
 #define ELABEL(x)
 #define LABEL_PTR(x) &LABEL(x)
 
-#if defined __has_attribute
-#if __has_attribute (preserve_none)
+#if RBIMPL_HAS_ATTRIBUTE(preserve_none)
 #define ATTR_PRESERVE_NONE __attribute__((preserve_none))
 #endif
-#endif
 
 #ifdef ATTR_PRESERVE_NONE
 #define INSN_FUNC_CONV ATTR_PRESERVE_NONE
diff --git a/vm_opts.h b/vm_opts.h
index 5f3dd4dd8a..56d08bb6c8 100644
--- a/vm_opts.h
+++ b/vm_opts.h
@@ -10,6 +10,8 @@
 
 **********************************************************************/
 
+#include "ruby/internal/has/attribute.h"
+
 /* Compile options.
  * You can change these options at runtime by VM::CompileOption.
  * Following definitions are default values.
@@ -34,9 +36,13 @@
  * 2: call (function call for each insn dispatch)
  * 3: call continuation (musttail attribute)
  */
-//#ifndef OPT_THREADED_CODE
+#ifndef OPT_THREADED_CODE
+#if RBIMPL_HAS_ATTRIBUTE(musttail)
 #define OPT_THREADED_CODE 3
-//#endif
+#else
+#define OPT_THREADED_CODE 0
+#endif
+#endif
 
 #define OPT_DIRECT_THREADED_CODE   (OPT_THREADED_CODE == 0)
 #define OPT_TOKEN_THREADED_CODE    (OPT_THREADED_CODE == 1)