/UName, /u - Remove Predefined Names (Windows CE 5.0)
These options undefine previously defined symbols. /U undefines the specified symbol. /u undefines all previously defined symbols.
These names are useful in writing portable programs. For instance, you can use them with compiler directives to conditionally compile parts of a program, depending what processor and operating system you use.
One or more spaces can separate /U and Name. You can specify more than one /U option on the same command line. You can define an unlimited number of identifiers.
Neither option can undefine symbols created with the #define directive.
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