Re: Big GCC bug!!! [Was: Re: Do not misuse Coverity please]

[Robert Hancock]

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
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Home Page: http://www.roberthancock.com/

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