c++ - Initialization during construction? -

i wrote following code:

struct a{     int a;     int b;     a(int c): a(c), b(a){ } };   int main() {     b(10); }

now, i'm not sure initializing b a a(c), b(a). ok or may cause ub?

yes, okay. members initialized in order declared in class. note order of initializers doesn't matter, work (but not practice):

struct a{     int a;     int b;     a(int c): b(a), a(c) { } };

but not work:

struct a{     int b;     int a;     a(int c) : a(c), b(a) { }  };

some compilers can give warning if initializer order doesn't match declaration order.

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