diff --git a/src/c/symbols_list.h b/src/c/symbols_list.h
index 811624381..3f7b993df 100755
--- a/src/c/symbols_list.h
+++ b/src/c/symbols_list.h
@@ -1847,6 +1847,7 @@ cl_symbols[] = {
 {EXT_ "LISP-STACK", EXT_ORDINARY, NULL, -1, OBJNULL},
 {EXT_ "C-STACK", EXT_ORDINARY, NULL, -1, OBJNULL},
 {EXT_ "HEAP-SIZE", EXT_ORDINARY, NULL, -1, OBJNULL},
+{EXT_ "ILLEGAL-INSTRUCTION", EXT_ORDINARY, NULL, -1, OBJNULL},
 {EXT_ "SET-LIMIT", EXT_ORDINARY, si_set_limit, 2, OBJNULL},
 {EXT_ "GET-LIMIT", EXT_ORDINARY, si_get_limit, 1, OBJNULL},
 {EXT_ "SEGMENTATION-VIOLATION", EXT_ORDINARY, NULL, -1, OBJNULL},
diff --git a/src/c/symbols_list2.h b/src/c/symbols_list2.h
index 42052a18e..a0773b1a3 100644
--- a/src/c/symbols_list2.h
+++ b/src/c/symbols_list2.h
@@ -1847,6 +1847,7 @@ cl_symbols[] = {
 {EXT_ "LISP-STACK",NULL},
 {EXT_ "C-STACK",NULL},
 {EXT_ "HEAP-SIZE",NULL},
+{EXT_ "ILLEGAL-INSTRUCTION",NULL},
 {EXT_ "SET-LIMIT","si_set_limit"},
 {EXT_ "GET-LIMIT","si_get_limit"},
 {EXT_ "SEGMENTATION-VIOLATION",NULL},
diff --git a/src/c/unixint.d b/src/c/unixint.d
index d2cea00ff..0310a5e4e 100644
--- a/src/c/unixint.d
+++ b/src/c/unixint.d
@@ -362,6 +362,10 @@ handler_fn_protype(lisp_signal_handler, int sig, siginfo_t *info, void *aux)
 	case SIGBUS:
                 return @'ext::segmentation-violation';
 #endif
+#ifdef SIGILL
+	case SIGILL:
+                return @'ext::illegal-instruction';
+#endif
 #ifdef SIGCHLD
         case SIGCHLD:
                 return SYM_FUN(@'si::wait-for-all-processes');
@@ -845,21 +849,21 @@ ecl_interrupt_process(cl_object process, cl_object function)
          * - In POSIX systems it sends a user level interrupt to
          *   the thread, which then decides how to act.
          */
-	/* Trivial spinlock to ensure that the process is past
-	 * the section where it establishes a CATCH */
-	while (process->process.phase == ECL_PROCESS_BOOTING)
-		ecl_musleep(0.0, 0);
-	/* And then only care when the process is really active, for
-	 * otherwise the signal will be ignored. */
-	if (process->process.phase == ECL_PROCESS_ACTIVE) {
-		/* If FUNCTION is NIL, we just intend to wake up the
-		 * process from some call to ecl_musleep() */
-		if (!Null(function)) {
+	if (!Null(function)) {
+		/* Trivial spinlock to ensure that the process is past
+		 * the section where it establishes a CATCH */
+		while (process->process.phase == ECL_PROCESS_BOOTING)
+			ecl_musleep(0.0, 0);
+		/* And then only care when the process is really active, for
+		 * otherwise the signal will be ignored. */
+		if (process->process.phase == ECL_PROCESS_ACTIVE) {
+			/* If FUNCTION is NIL, we just intend to wake up the
+			 * process from some call to ecl_musleep() */
 			function = si_coerce_to_function(function);
 			queue_signal(process->process.env, function);
 		}
-		do_interrupt_thread(process);
 	}
+	do_interrupt_thread(process);
 }
 #endif /* ECL_THREADS */
 
@@ -920,7 +924,7 @@ _ecl_w32_exception_filter(struct _EXCEPTION_POINTERS* ep)
                         return EXCEPTION_CONTINUE_EXECUTION;
 		/* Catch illegal instruction */
 		case EXCEPTION_ILLEGAL_INSTRUCTION:
-			handle_or_queue(MAKE_FIXNUM(SIGILL), 0);
+			handle_or_queue(@'ext::illegal-instruction', 0);
 			return EXCEPTION_CONTINUE_EXECUTION;
 		/* Do not catch anything else */
 		default:
@@ -1207,6 +1211,11 @@ install_synchronous_signal_handlers()
 		mysignal(SIGPIPE, non_evil_signal_handler);
 	}
 #endif
+#ifdef SIGILL
+	if (ecl_get_option(ECL_OPT_TRAP_SIGILL)) {
+		mysignal(SIGILL, non_evil_signal_handler);
+	}
+#endif
 }
 
 /*
diff --git a/src/clos/conditions.lsp b/src/clos/conditions.lsp
index 4220316ee..bd152be78 100644
--- a/src/clos/conditions.lsp
+++ b/src/clos/conditions.lsp
@@ -511,6 +511,10 @@ or return to an outer frame, undoing all the function calls so far."
   (:REPORT "Memory limit reached. Please jump to an outer pointer, quit program and enlarge the
 memory limits before executing the program again."))
 
+(define-condition ext:illegal-instruction (serious-condition)
+  ()
+  (:REPORT "Illegal instruction."))
+
 (define-condition ext:unix-signal-received ()
   ((code :type fixnum
          :initform 0