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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 -Os and above in 32-bit mode on x86_64-linux-gnu"
href="https://llvm.org/bugs/show_bug.cgi?id=27804">27804</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>wrong code at -Os and above 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>chengniansun@gmail.com
</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 -Os, -O2, and -O3 in 32-bit
mode (not in 64-bit mode) on x86_64-linux-gnu.
$: clang-trunk -v
clang version 3.9.0 (trunk 269748)
Target: x86_64-unknown-linux-gnu
Thread model: posix
InstalledDir: /usr/local/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
Found candidate GCC installation:
/usr/local/bin/../lib/gcc/x86_64-unknown-linux-gnu/4.6.3
Found candidate GCC installation:
/usr/local/bin/../lib/gcc/x86_64-unknown-linux-gnu/4.7.4
Found candidate GCC installation:
/usr/local/bin/../lib/gcc/x86_64-unknown-linux-gnu/4.8.2
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 small.c -w -m32 -Os ; ./a.out
Floating point exception (core dumped)
$: clang-trunk small.c -w -m32 -O2 ; ./a.out
Floating point exception (core dumped)
$: clang-trunk small.c -w -m32 -O3 ; ./a.out
Floating point exception (core dumped)
$: clang-trunk small.c -w -m32 -O1 ; ./a.out
l_5906=1
$:
$: cat small.c
volatile short a, g, l = 1;
char b, e;
int c, d, h, i = -7L, k, m;
short f;
short j;
static short fn1() {
unsigned short n = 4;
for (; b >= 0; b--)
;
for (;;) {
int o = ~(e && f && j), p = ~(~(h % ~k ^ e) & b);
char q = ~(b | e) ^ (p && o ^ j) >> ~i;
short r = (n & h && q) | ~(o | (e | p)), s = (h && q && j && i % l) * e;
if (e)
k = r | b;
j = s;
if (!(c >= 0)) {
h++;
printf("g_5326=%lld\n", (long long)2);
}
a / b &&a;
short t = ~g;
n = t;
L1:
if (l) {
printf("l_5906=%lld\n", (long long)l);
goto L2;
}
continue;
L2:
if (d)
goto L1;
return m;
}
}
int main() { fn1(); }
$:</pre>
</div>
</p>
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