MJIT: Cancel all on disastrous situations (#7019)

I noticed this while running test_yjit with --mjit-call-threshold=1, 
which redefines `Integer#<`. When Ruby is monkey-patched, 
MJIT itself could be broken.

Similarly, Ruby scripts could break MJIT in many different ways. I
prepared the same set of hooks as YJIT so that we could possibly
override it and disable it on those moments. Every constant under
RubyVM::MJIT is private and thus it's an unsupported behavior though.

1 files changed, 2 insertions, 0 deletions

diff --git a/ractor.c b/ractor.c
index fddcec382b..e608e4e232 100644
--- a/ractor.c
+++ b/ractor.c
@@ -17,6 +17,7 @@
 #include "gc.h"
 #include "transient_heap.h"
 #include "yjit.h"
+#include "mjit.h"
 
 VALUE rb_cRactor;
 
@@ -1606,6 +1607,7 @@ ractor_create(rb_execution_context_t *ec, VALUE self, VALUE loc, VALUE name, VAL
     r->debug = cr->debug;
 
     rb_yjit_before_ractor_spawn();
+    rb_mjit_before_ractor_spawn();
     rb_thread_create_ractor(r, args, block);
 
     RB_GC_GUARD(rv);