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<base href="https://llvm.org/bugs/" />
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<body><table border="1" cellspacing="0" cellpadding="8">
<tr>
<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW --- - wrong code at -O3 in 32-bit mode on x86_64-linux-gnu"
href="https://llvm.org/bugs/show_bug.cgi?id=27611">27611</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>wrong code at -O3 in 32-bit mode on x86_64-linux-gnu
</td>
</tr>
<tr>
<th>Product</th>
<td>clang
</td>
</tr>
<tr>
<th>Version</th>
<td>trunk
</td>
</tr>
<tr>
<th>Hardware</th>
<td>PC
</td>
</tr>
<tr>
<th>OS</th>
<td>All
</td>
</tr>
<tr>
<th>Status</th>
<td>NEW
</td>
</tr>
<tr>
<th>Severity</th>
<td>normal
</td>
</tr>
<tr>
<th>Priority</th>
<td>P
</td>
</tr>
<tr>
<th>Component</th>
<td>-New Bugs
</td>
</tr>
<tr>
<th>Assignee</th>
<td>unassignedclangbugs@nondot.org
</td>
</tr>
<tr>
<th>Reporter</th>
<td>su@cs.ucdavis.edu
</td>
</tr>
<tr>
<th>CC</th>
<td>llvm-bugs@lists.llvm.org
</td>
</tr>
<tr>
<th>Classification</th>
<td>Unclassified
</td>
</tr></table>
<p>
<div>
<pre>The following code is miscompiled by the trunk at -O3 in the 32-bit mode (but
not in the 64-bit mode) on x86_64-linux-gnu.
This is a regression from 3.8.x.
$ clang-trunk -v
clang version 3.9.0 (trunk 268212)
Target: x86_64-unknown-linux-gnu
Thread model: posix
InstalledDir: /usr/local/tools/bin
Found candidate GCC installation: /usr/lib/gcc/i686-linux-gnu/4.9
Found candidate GCC installation: /usr/lib/gcc/i686-linux-gnu/4.9.3
Found candidate GCC installation: /usr/lib/gcc/i686-linux-gnu/5.3.0
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.4
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.4.7
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.6
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.6.4
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.7
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.7.3
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.8
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.8.5
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.9
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.9.3
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/5.3.0
Selected GCC installation: /usr/lib/gcc/x86_64-linux-gnu/4.9
Candidate multilib: .;@m64
Candidate multilib: 32;@m32
Candidate multilib: x32;@mx32
Selected multilib: .;@m64
$
$ clang-trunk -m32 -O2 small.c; ./a.out
$ clang-3.8 -m32 -O3 small.c; ./a.out
$ clang-trunk -m64 -O3 small.c; ./a.out
$
$ clang-trunk -m32 -O3 small.c
$ ./a.out
Floating point exception (core dumped)
$
-----------------------------------------
int printf (const char *, ...);
unsigned a;
int h, e, g, i;
static int c = 7, f;
char j = 6, d;
struct S1
{
char f1;
char f2;
int f3;
} b;
void
fn1 ()
{
int k = 6, o = 248, l = 0;
struct S1 n = { 4, 0, 0 };
if (j)
{
int q = g;
lbl:
l = l << h / (q || c << 0) << n.f2;
if (k)
n.f3 = ~(-e | (o - 94967289));
if (!n.f3)
{
printf ("\n");
goto lbl;
}
if (!c)
{
n = b;
goto lbl;
}
if (b.f2)
{
n.f2 = f;
for (; k > 5; k = 8)
;
}
}
o = a;
char s = i / n.f1;
d = s;
if (!n.f1)
goto lbl;
if (l)
c = 0;
}
int
main ()
{
fn1 ();
return 0;
}</pre>
</div>
</p>
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