Microsoft WindowsÔ can move segments dynamically. As a result of dynamic heap compaction, the contents of handles can be modified. The /Ow option specifies that your program does not perform any aliasing except between functions, so the compiler does not perform optimizations across function calls. See “Assuming No Aliasing (/Oa and /Ow)” for more information.
The /GA and /GD options optimize the entry/exit code for protected-mode Windows applications and DLLs, respectively. For more information on these options, see Chapter 13, “CL Command Reference,” of the Environment and Tools manual.