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<base href="https://llvm.org/bugs/" />
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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW " title="NEW --- - WinEHPrepare failed to demote instruction" href="https://urldefense.proofpoint.com/v2/url?u=https-3A__llvm.org_bugs_show-5Fbug.cgi-3Fid-3D23884&d=AwMBaQ&c=8hUWFZcy2Z-Za5rBPlktOQ&r=pF93YEPyB-J_PERP4DUZOJDzFVX5ZQ57vQk33wu0vio&m=hFkR_ZBVNA_A4RUBVco0Mn_-r3gXH_AAYmlogi8bkpA&s=HGHlwOcZIpsY-o4En3_TecohkU_lCkonITI2gUJpLGw&e=">23884</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>WinEHPrepare failed to demote instruction
</td>
</tr>
<tr>
<th>Product</th>
<td>libraries
</td>
</tr>
<tr>
<th>Version</th>
<td>trunk
</td>
</tr>
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<th>Hardware</th>
<td>PC
</td>
</tr>
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<th>OS</th>
<td>All
</td>
</tr>
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<th>Status</th>
<td>NEW
</td>
</tr>
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<th>Severity</th>
<td>normal
</td>
</tr>
<tr>
<th>Priority</th>
<td>P
</td>
</tr>
<tr>
<th>Component</th>
<td>Common Code Generator Code
</td>
</tr>
<tr>
<th>Assignee</th>
<td>unassignedbugs@nondot.org
</td>
</tr>
<tr>
<th>Reporter</th>
<td>alex@crichton.co
</td>
</tr>
<tr>
<th>CC</th>
<td>llvmbugs@cs.uiuc.edu
</td>
</tr>
<tr>
<th>Classification</th>
<td>Unclassified
</td>
</tr></table>
<p>
<div>
<pre>Compiling this IR:
```
target triple = "x86_64-pc-windows-msvc"
declare i32 @__C_specific_handler(...)
declare void @bar()
declare void @baz()
declare void @free(i8*)
define void @foo() {
invoke void @baz()
to label %normal unwind label %unwind1
normal:
unreachable
unwind1:
%lp5 = landingpad { i8*, i32 } personality i32 (...)* @__C_specific_handler
cleanup
%rem = load i8*, i8** undef, align 8
invoke void @bar()
to label %normal unwind label %unwind2
unwind2:
%lp6 = landingpad { i8*, i32 } personality i32 (...)* @__C_specific_handler
cleanup
invoke void @baz()
to label %normal2 unwind label %unwind3
normal2:
call void @free(i8* %rem)
unreachable
unwind3:
%lp4 = landingpad { i8*, i32 } personality i32 (...)* @__C_specific_handler
cleanup
unreachable
}
```
will end up yielding the following when compiled with llc:
Failed to demote instruction used in exception handler of function foo:
%rem = load i8*, i8** undef, align 8
LLVM ERROR: WinEHPrepare failed to demote instruction
This may be a dupe of one of these bugs, but I didn't see a reduced version of
them so I wasn't sure unfortnately:
* <a class="bz_bug_link
bz_status_NEW " title="NEW --- - WinEHPrepare failed to demote instruction" href="show_bug.cgi?id=23427">https://llvm.org/bugs/show_bug.cgi?id=23427</a>
* <a class="bz_bug_link
bz_status_NEW " title="NEW --- - WinEHPrepare failed to demote instruction" href="show_bug.cgi?id=23557">https://llvm.org/bugs/show_bug.cgi?id=23557</a></pre>
</div>
</p>
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