Developer Guide and Reference

Contents

U

Undefines any definition currently in effect for the specified
macro
.

Syntax

Linux:
-U
name
macOS:
-U
name
Windows:
/U
name
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.
Alternate Options
None
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>