Quirrell's "death" in PS/SS

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No: HPFGUIDX 40299

Hi:  Longtime lurker, first-time poster. 

Was re-reading PS/SS recently and something struck me:  do we really 
know that Quirrell is dead?  In PS/SS 17, Dumbledore 
says "[Voldemort] left Quirrell to die."  This isn't the same thing 
as saying, "Voldemort killed Quirrell," or "Quirrell died when 
Voldemort fled his body," especially given the precision of JKR's 
prose.  You can "leave someone to die" without its resulting in the 
person's death.  

Are there any other canon references to Quirrell's death?

(Sorry if this has been discussed before.)

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