description | title | ms.date | f1_keywords | helpviewer_keywords | ms.assetid | |||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Learn more about: /J (Default char Type Is unsigned) |
/J (Default char Type Is unsigned) |
11/04/2016 |
|
|
50973667-6638-491e-9c41-bff73acae19f |
Changes the default char
type from signed char
to unsigned char
, and the char
type is zero-extended when it is widened to an int
type.
/J
If a char
value is explicitly declared as signed
, the /J option does not affect it, and the value is sign-extended when it is widened to an int
type.
The /J option defines _CHAR_UNSIGNED
, which is used with #ifndef
in the LIMITS.h file to define the range of the default char
type.
ANSI C and C++ do not require a specific implementation of the char
type. This option is useful when you are working with character data that will eventually be translated into a language other than English.
Note
If you use this compiler option with ATL/MFC, an error might be generated. Although you could disable this error by defining _ATL_ALLOW_CHAR_UNSIGNED
, this workaround is not supported and may not always work.
-
Open your project's Property Pages dialog box. For details, see Set C++ compiler and build properties in Visual Studio.
-
Select the Configuration Properties > C/C++ > Command Line property page.
-
In Additional Options, enter the /J compiler option.
- See xref:Microsoft.VisualStudio.VCProjectEngine.VCCLCompilerTool.DefaultCharIsUnsigned%2A.
MSVC Compiler Options
MSVC Compiler Command-Line Syntax
Set C++ compiler and build properties in Visual Studio