I may have found the answer. My Perl distro (ActiveState, which is a 5.6.1 Win32 port), is compiled without either USE_THREADS or USE_ITHREADS. I'm not sure why that should matter (aren't these just for INTERNAL Perl threading?) but I've discovered that if I call eval_pv() from a __different O/S thread__ than the one I initialized the interpreter in, it traps. If I call from the same thread, it doesn't. I debugged it a little and found some calls to various TLS functions, so it appears that the simple expedient of storing my_perl in a global variable wasn't enough. Behind the scenes a pointer to it was getting stashed in thread-local storage, so that when I switched context over to my other thread, the pointer was null (different TLS instance) and we trapped as soon as we tried to use the interpreter pointer. VERY non-intuitive... As a C++ coder, I assume that if I dereference a global variable, it will have the same value over all functions in the module (assuming it isn't changed locally). However, this doesn't seem to match the actual behavior I'm seeing...

In reply to Re: Re: Unorthodox Embedding/XS madness! by Ouroborous
in thread Unorthodox Embedding/XS madness! by Ouroborous

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