<div dir="ltr"><br><br><div class="gmail_quote"><div dir="ltr">On Mon, Jan 9, 2017 at 11:22 AM Sean Callanan via Phabricator <<a href="mailto:reviews@reviews.llvm.org">reviews@reviews.llvm.org</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">spyffe added a comment.<br class="gmail_msg">
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According to the GCC 5 changelist <<a href="https://gcc.gnu.org/gcc-5/changes.html" rel="noreferrer" class="gmail_msg" target="_blank">https://gcc.gnu.org/gcc-5/changes.html</a>>, support for `std::aligned_union` was introduced with GCC 5.<br class="gmail_msg">
I was able to verify with Compiler Explorer <<a href="http://gcc.godbolt.org" rel="noreferrer" class="gmail_msg" target="_blank">http://gcc.godbolt.org</a>> that `std::aligned_union` is **unsupported** (as in, not found) by 4.9.5. It is supported by 5.1.<br class="gmail_msg"></blockquote><div><br>Ah, pity - thanks for checking!<br><br>I was going off <a href="https://gcc.gnu.org/projects/cxx-status.html#cxx11">https://gcc.gnu.org/projects/cxx-status.html#cxx11</a> which mentions 4.8 for library alignment features, evidently not all of them.<br> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
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According to Microsoft <<a href="https://msdn.microsoft.com/en-us/library/dn986846.aspx" rel="noreferrer" class="gmail_msg" target="_blank">https://msdn.microsoft.com/en-us/library/dn986846.aspx</a>>, Visual Studio 2015 supports `std::aligned_union`.<br class="gmail_msg">
I was able to verify with "Compile Visual Studio C++ Online" <<a href="http://rextester.com/l/cpp_online_compiler_visual" rel="noreferrer" class="gmail_msg" target="_blank">http://rextester.com/l/cpp_online_compiler_visual</a>> that Visual C++ 2015 supports it.<br class="gmail_msg">
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<a href="https://reviews.llvm.org/D28429" rel="noreferrer" class="gmail_msg" target="_blank">https://reviews.llvm.org/D28429</a><br class="gmail_msg">
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