Compiler Warning (level 3) C4640
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Compiler Warning (level 3) C4640

Error Message

'instance' : construction of local static object is not thread-safe

A static instance of an object is not thread safe.

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

The following sample generates C4640:

// C4640.cpp
// compile with: /W3
#pragma warning(default:4640)

class X {
   X() {

void f() {
   static X aX;   // C4640

int main() {
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