/Obn - Control Inline Expansion

This option controls the inline expansion of functions, where n is a digit from zero through two. The following table shows the values for n.

Value	Description
0	Disables inline expansion, the default value. This option allows you to turn off inlining.
1	Expands only functions marked as inline or __inline or in a C++ member function defined within a class declaration, which is default with /O1, /O2, and /Ox.
2	Expands functions marked as inline or __inline and any other function that the compiler chooses. Expansion occurs at compiler discretion, often referred to as auto-inlining.

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