Date: Wed, 30 Mar 2005 17:57:49 -0600
From: Robert Hancock <hancockr@shaw.ca>
Subject: Re: Big GCC bug!!! [Was: Re: Do not misuse Coverity please]
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Kyle Moffett wrote:
> Dereferencing null pointers is relied upon by a number of various
> emulators and such, and is "platform-defined" in the standard, so
> since Linux allows mmap at NULL, GCC shouldn't optimize that case
> any differently.

 From the GCC manual: "The compiler assumes that dereferencing a null 
pointer would have halted the program. If a pointer is checked after it 
has already been dereferenced, it cannot be null. In some environments, 
this assumption is not true, and programs can safely dereference null 
pointers. Use -fno-delete-null-pointer-checks to disable this 
optimization for programs which depend on that behavior. "

-- 
Robert Hancock      Saskatoon, SK, Canada
To email, remove "nospam" from hancockr@nospamshaw.ca
Home Page: http://www.roberthancock.com/

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