<html>
<head>
<base href="http://llvm.org/bugs/" />
</head>
<body><table border="1" cellspacing="0" cellpadding="8">
<tr>
<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW --- - MS ABI: layout of class with vbptr and vfptr is wrong"
href="http://llvm.org/bugs/show_bug.cgi?id=19180">19180</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>MS ABI: layout of class with vbptr and vfptr is wrong
</td>
</tr>
<tr>
<th>Product</th>
<td>clang
</td>
</tr>
<tr>
<th>Version</th>
<td>unspecified
</td>
</tr>
<tr>
<th>Hardware</th>
<td>PC
</td>
</tr>
<tr>
<th>OS</th>
<td>Linux
</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>LLVM Codegen
</td>
</tr>
<tr>
<th>Assignee</th>
<td>unassignedclangbugs@nondot.org
</td>
</tr>
<tr>
<th>Reporter</th>
<td>david.majnemer@gmail.com
</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>consider:
extern "C" int printf(const char *, ...);
static char buffer[419430400];
inline void *operator new(size_t, void *pv) { return pv; }
struct A {
char fiel;
A() {
printf("A(fiel): %d\n", &fiel - buffer);
}
};
struct B {
char fiel;
B() {
printf("B(fiel): %d\n", &fiel - buffer);
}
virtual void OverrideMethod() {}
};
struct C {
char fiel;
C() {
printf("C(fiel): %d\n", &fiel - buffer);
}
};
struct D : public A, public B, public virtual C {
D() {
printf("D(this): %d\n", (char *)this - buffer);
printf("D(A ): %d\n", (char *)(A *)this - buffer);
printf("D(B ): %d\n", (char *)(B *)this - buffer);
printf("D(C ): %d\n", (char *)(C *)this - buffer);
}
};
int main() { new (buffer) D; }
MSVC gives:
C(fiel): 16
A(fiel): 12
B(fiel): 4
D(this): 0
D(A ): 12
D(B ): 0
D(C ): 16
clang gives:
C(fiel): 20
A(fiel): 8
B(fiel): 4
D(this): 0
D(A ): 8
D(B ): 0
D(C ): 20</pre>
</div>
</p>
<hr>
<span>You are receiving this mail because:</span>
<ul>
<li>You are on the CC list for the bug.</li>
</ul>
</body>
</html>