WARNING: I can't guarantee the veracity of this answer. I'm still mostly a novice when it comes to Perl internals.

Looking at the definition of ENTER and LEAVE I see: 

#define ENTER push_scope()
#define LEAVE pop_scope()

[download]

And SAVETMPS and FREETMPS are: 

#define SAVETMPS save_int((int*)&PL_tmps_floor), PL_tmps_floor = PL_tm
+ps_ix
#define FREETMPS if (PL_tmps_ix > PL_tmps_floor) free_tmps()

[download]

So ENTER/LEAVE is responsible for managing the scope stack (growing it, adjusting pointers) and SAVETMPS/FREETMPS just handles the temp stack, and calls free_tmps() if needed.

I imagine that leaves you with more questions than you came in with, but I'll have to leave it at that. No time to dig further now...

-sam

In reply to Re: ENTER vs. SAVETMPS by samtregar
in thread ENTER vs. SAVETMPS by rsteinke

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