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<p class="MsoNormal">I was looking at the wrong file. Thanks for the pointer and quick reply!<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><b><span style="font-size:12.0pt;color:black">From: </span></b><span style="font-size:12.0pt;color:black">Eric Fiselier <eric@efcs.ca><br>
<b>Date: </b>Monday, November 18, 2019 at 7:12 PM<br>
<b>To: </b>Shoaib Meenai <smeenai@fb.com><br>
<b>Cc: </b>Libc++ Dev <libcxx-dev@lists.llvm.org><br>
<b>Subject: </b>Re: [libcxx-dev] exception_ptr reference counting<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">The relevant implementation of exception_ptr is here (<a href="https://github.com/llvm-mirror/libcxx/blob/master/src/support/runtime/exception_pointer_cxxabi.ipp">https://github.com/llvm-mirror/libcxx/blob/master/src/support/runtime/exception_pointer_cxxabi.ipp</a>)<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">The exception header is reference counted, my very quick and dirty reading of the implementation suggests that we handle the reference counting correctly.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">please let me know if I've overlooked something.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt"><o:p> </o:p></p>
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<p class="MsoNormal">On Mon, Nov 18, 2019, 9:34 PM Shoaib Meenai via libcxx-dev <<a href="mailto:libcxx-dev@lists.llvm.org" target="_blank">libcxx-dev@lists.llvm.org</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">According to cppreference [1]:<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">> The exception object referenced by an std::exception_ptr remains valid as long as there remains at least one std::exception_ptr that is referencing it: std::exception_ptr is a
shared-ownership smart pointer<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">I don’t actually see any code in libc++’s implementation to prolong the lifetime of an exception object in case there are exception_ptrs pointing to it. I feel like I’m missing
something obvious; how is this case handled?<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">[1]
<a href="https://urldefense.proofpoint.com/v2/url?u=https-3A__en.cppreference.com_w_cpp_error_exception-5Fptr&d=DwMFaQ&c=5VD0RTtNlTh3ycd41b3MUw&r=o3kDXzdBUE3ljQXKeTWOMw&m=VkjyXAuvjXpKf__9-xKnfAMLxP0JPRm6FDBryIjUaqw&s=sn4cT-nnVjBLwB3x9VvB7MdoYr7XLmxbVTTcG1VolR0&e=" target="_blank">
https://en.cppreference.com/w/cpp/error/exception_ptr</a><o:p></o:p></p>
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<p class="MsoNormal">_______________________________________________<br>
libcxx-dev mailing list<br>
<a href="mailto:libcxx-dev@lists.llvm.org" target="_blank">libcxx-dev@lists.llvm.org</a><br>
<a href="https://urldefense.proofpoint.com/v2/url?u=https-3A__lists.llvm.org_cgi-2Dbin_mailman_listinfo_libcxx-2Ddev&d=DwMFaQ&c=5VD0RTtNlTh3ycd41b3MUw&r=o3kDXzdBUE3ljQXKeTWOMw&m=VkjyXAuvjXpKf__9-xKnfAMLxP0JPRm6FDBryIjUaqw&s=_gIdEQ4hi3njB56qBEa-SO0y_Tyfsf-SldapOSyU3IM&e=" target="_blank">https://lists.llvm.org/cgi-bin/mailman/listinfo/libcxx-dev</a><o:p></o:p></p>
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