CNI changes (Was: Binary Compatibility)

Tom Tromey
Mon Aug 4 17:17:00 GMT 2003

Andrew> Besides, I have some vague memory that Java semantics actually
Andrew> require storing into an int field to be atomic.  [Looks it
Andrew> up.]  Oh yes, according to Section 8.3 of the VMspec that
Andrew> seems to be the case.  But a method pointer might on some
Andrew> machines be a long rather than an int, so synchronization may
Andrew> be required.  I get it now, I think.

I've never even been certain that we correctly implement the java
rules for atomicity of stores.  These rules are a requirement on us to
generate the correct code...

Changing the lookup code will make things a little worse.  We'll need
an extra function call and a synchronization for every JNI method.  It
would be nice not to do this if possible.  This is an area I really
don't know much about.  Can we tell gcc that we need a certain store
to be atomic?


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