/Za - Disable Language Extensions (Windows CE 5.0)
This option disables language extensions to the ANSI C standard. Language extensions are enabled when the /Ze - Enable Language Extensions option is in effect, and disabled when the /Za option is in effect. For more information about these extensions, see Microsoft Extensions to C and C++.
Use the /Za option if you plan to port your program to other environments. The /Za option tells the compiler to treat extended keywords as simple identifiers and to disable the other extensions listed previously.
When you specify /Za, the compiler automatically defines the __STDC__ identifier. In the include files provided with the C run-time libraries, this identifier is used with #ifndef to control use of the __cdecl keyword on library function prototypes.
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