Here is the Stack overflow link that i have shared the problem (http://stackoverflow.com/questions/16798079/captured-variable-hides-passed-variable-in-lambda-how-to-unhide/16798406#16798406)

I will expand the example here

int main()
{
    int a = 1;
    std::cout<<[=,&a](int a,int b){return a+b;}(99,1);
    return 0;
}

Here the output is 2 rather than 100.

as the answer in the link says this problem in present in gcc 4.7.2 and gcc 4.8