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Compiler Warning (level 4) C4431

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missing type specifier - int assumed. Note: C no longer supports default-int

This error can be generated as a result of compiler conformance work that was done for Visual Studio 2005: Visual C++ no longer creates untyped identifiers as int by default. The type of an identifier must be specified explicitly.

This warning is off by default. See Compiler Warnings That Are Off by Default for more information.

Example

The following sample generates C4431.

// C4431.c
// compile with: /c /W4
#pragma warning(default:4431)
i;   // C4431
int i;   // OK