Should I free this memory?

Hello,

My C function:

PG_FUNCTION_INFO_V1(my_function);
Datum my_function(PG_FUNCTION_ARGS)
{
MemoryContext old_context;
int * p = NULL;
float f = 0.0;

old_context = MemoryContextSwitchTo(fcinfo->flinfo->fn_mcxt);
p = palloc(100);
MemoryContextSwitchTo(old_context);

// do some other stuff

PG_RETURN_FLOAT8(f); // I didn't call pfree(p)
}

Should I free the memory allocated for p? I'm getting memory leaks
when I don't free the memory, and they disappear when I call pfree(p);

I think the response is "yes", I should free the memory (looking at
the results), but I'm not sure why. So, maybe my real doubt is: which
memory context are fcinfo->flinfo->fn_mcxt and old_context? In which
context should I work and why?

Many thanks in advance, and best regards

--
Jorge Arévalo
Internet & Mobilty Division, DEIMOS
jorge(dot)arevalo(at)deimos-space(dot)com
http://es.linkedin.com/in/jorgearevalo80
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