Visible to Intel only — GUID: GUID-E9DEC854-3E5F-45F5-B250-C3DDCA6715FC
Visible to Intel only — GUID: GUID-E9DEC854-3E5F-45F5-B250-C3DDCA6715FC
U
Undefines any definition currently in effect for the specified macro.
Syntax
Linux: |
-Uname |
macOS: |
-Uname |
Windows: |
/Uname |
Arguments
name |
Is the name of the macro to be undefined. |
Default
OFF |
Macro definitions are in effect until they are undefined. |
Description
This option undefines any definition currently in effect for the specified macro. It is equivalent to an #undef preprocessing directive.
On Windows systems, use the /u option to undefine all previously defined preprocessor values.
IDE Equivalent
Visual Studio: Preprocessor > Undefine Preprocessor Definitions
Eclipse: Preprocessor > Undefine Preprocessor Definitions
Xcode: Preprocessor > Undefine Preprocessor Definitions
Alternate Options
None
Example
To undefine a macro, enter the following command:
On Windows* systems:
icl /Uia64 prog1.cpp
On Linux* systems:
icpc -Uia64 prog1.cpp
On macOS systems:
icpc -Uia64 prog1.cpp
If you attempt to undefine an ANSI C macro, the compiler will emit an error:
invalid macro undefinition: <name of macro>