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copied!<p>I ran into this breaking change when I used GCC. The compiler printed an error for code like this:</p> <pre><code>void foo(const unsigned long long &i) { unsigned int a[2] = {i & 0xFFFFFFFF, i >> 32}; } </code></pre> <blockquote> <p>In function <code>void foo(const long long unsigned int&)</code>:</p> <p>error: narrowing conversion of <code>(((long long unsigned int)i) & 4294967295ull)</code> from <code>long long unsigned int</code> to <code>unsigned int</code> inside { }</p> <p>error: narrowing conversion of <code>(((long long unsigned int)i) >> 32)</code> from <code>long long unsigned int</code> to <code>unsigned int</code> inside { }</p> </blockquote> <p>Fortunately, the error messages were straightforward and the fix was simple:</p> <pre><code>void foo(const unsigned long long &i) { unsigned int a[2] = {static_cast<unsigned int>(i & 0xFFFFFFFF), static_cast<unsigned int>(i >> 32)}; } </code></pre> <p>The code was in an external library, with only two occurrences in one file. I don't think the breaking change will affect much code. Novices might <a href="https://stackoverflow.com/questions/4490111/have-narrowing-conversion-error-in-c-arm-from-android-ndk" title="Have narrowing conversion error in C++ arm from Android NDK - Stack Overflow">get</a> <a href="https://stackoverflow.com/questions/3719848/char-and-initializer-lists" title="conversion - char and initializer lists - Stack Overflow">confused,</a> though.</p>

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