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 [EMAIL PROTECTED] Home Page: http://www.roberthancock.com/
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