<p dir="auto"><a class="user-mention notranslate" data-hovercard-type="user" data-hovercard-url="/users/alexcrichton/hovercard" data-octo-click="hovercard-link-click" data-octo-dimensions="link_type:self" href="https://github.com/alexcrichton">@alexcrichton</a> has indicated this may be related to using newer versions of gcc, which might explain why it doesn't fail on the buildbot machines.</p>
<p dir="auto">The segfault occurs while running the <code class="notranslate">tailcallelim</code> llvm pass on <code class="notranslate">ast::Pat_::drop()</code>, possibly during the prerequisite <code class="notranslate">tti</code> analysis.</p>
<p dir="auto">Turning on any kind of debug information for either rust or llvm causes the problem to disappear.</p>
<p dir="auto">Just a heads-up to others: mingw-w64 (not sure about other platforms) GCC 5.x appears to be subtly mis-compiling LLVM, which results in a segmentation fault during rustc's codegen.<br>
I've seen this with x86_64-5.1.0- and i686-5.2.0- toolchains.  In the former case LLVM had to be compiled with asserts (--enable-llvm-assertions) for this to occur.</p>
<p dir="auto">GCC 4.9.3 seems to be OK.</p>