struct test{

int a=1111111;

}test;

vincentdeMacBook-Air:datasturte vincent$ g++ struct.cpp -o structppstruct.cpp:4:6: warning: in-class initialization of non-static data member is a      C++11 extension [-Wc++11-extensions]int a=11111111;     ^1 warning generated.

struct test{

const int a=1111111;

}test;

vincentdeMacBook-Air:datasturte vincent$ g++ struct.cpp -o structppstruct.cpp:4:12: warning: in-class initialization of non-static data member is a      C++11 extension [-Wc++11-extensions]const int a=11111111;           ^struct.cpp:29:4: error: cannot assign to non-static data member 'a' with      const-qualified type 'const int'q.a=10;~~~^struct.cpp:4:11: note: non-static data member 'a' declared const hereconst int a=11111111;~~~~~~~~~~^~~~~~~~~~1 warning and 1 error generated.vincentdeMacBook-Air:datasturte vincent$ g++ struct.cpp -o structppstruct.cpp:29:4: error: cannot assign to static data member 'a' with      const-qualified type 'const int'q.a=10;~~~^

struct test{

static int a=11111111;

}test;

 

struct.cpp:4:18: note: static data member 'a' declared const herestatic const int a=11111111;~~~~~~~~~~~~~~~~~^~~~~~~~~~1 error generated. vincentdeMacBook-Air:datasturte vincent$ g++ struct.cpp -o structppstruct.cpp:4:12: error: non-const static data member must be initialized out of      linestatic int a=11111111;           ^ ~~~~~~~~1 error generated.

　　同样问题：http://stackoverflow.com/questions/13662441/c11-allows-in-class-initialization-of-non-static-and-non-const-members-what-c