c++ - Why a C-style typecasting is mandatory while initializing a POD data in initializer list? -

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struct pod { int i, j; };     class {   pod m_pod; public:   a() : m_pod({1,2}) {} // error   a() : m_pod(static_cast<pod>({1,2})) {} // error   a() : m_pod((pod) {1,2}) {} // ok! };

i see in old production code compiled g++34, until din't know feature.
g++ specific feature ? if not then, why typecasting needed , that's c-style cast allowed ?

the syntax you're using isn't initializer lists, it's initialization of class types outside of declarations. example:

pod p; p = (pod) {1, 2};

these called compound literals; added c in c99. aren't supported in c++; gcc allows them in c++ (and c89) extension. c++11 adds syntax:

p = pod({1, 2});

or in case:

a() : m_pod(pod({1,2})) {}

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