/U, /u (Undefine Symbols)
Visual Studio .NET 2003
/U[ ]symbol /u
where:
- symbol
- The symbol you want undefined.
Remarks
These options undefine previously defined symbols. /U undefines the specified symbol. /u undefines all previously defined symbols.
Neither option can undefine symbols created with the #define directive.
/u undefines the following Microsoft-specific macros. /U can undefine these options also.
| Symbol | Function |
|---|---|
| _CHAR_UNSIGNED | Default char type is unsigned. Defined when /J is specified. |
| _CPPRTTI | Defined for code compiled with the /GR (Enable Run-Time Type Information) option. |
| _CPPUNWIND | Defined for code compiled with the /GX (Enable Exception Handling) option. |
| _DLL | Defined when /MD is specified. |
| _M_IX86 | 1Defined as 500 for Blend (/GB), 300 for 80386 (/G3), 400 for 80486 (/G4), 500 for Pentium (/G5), and 600 for Pentium Pro, Pentium II, and Pentium III (/G6). |
| _MSC_VER | See Predefined Macros for more information. |
| _WIN32 | 1Defined for applications for WIN32. Always defined. |
| _MT | Defined when /MD or /MT is specified. |
1 x86 specific
To set this compiler option in the Visual Studio development environment
- Open the project's Property Pages dialog box. For details, see Setting Visual C++ Project Properties.
- Click the C/C++ folder.
- Click the Advanced property page.
- Modify the Undefine Preprocessor Definitions or Undefine All Preprocessor Definitions properties.
To set this compiler option programmatically
See UndefineAllPreprocessorDefinitions Property or UndefinePreprocessorDefinitions Property.
