<html>
<head>
<base href="https://bugs.llvm.org/">
</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 - [LLVM-COV] Dead code following a call site has wrong coverage."
href="https://bugs.llvm.org/show_bug.cgi?id=50839">50839</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>[LLVM-COV] Dead code following a call site has wrong coverage.
</td>
</tr>
<tr>
<th>Product</th>
<td>Runtime Libraries
</td>
</tr>
<tr>
<th>Version</th>
<td>11.0
</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>enhancement
</td>
</tr>
<tr>
<th>Priority</th>
<td>P
</td>
</tr>
<tr>
<th>Component</th>
<td>libprofile library
</td>
</tr>
<tr>
<th>Assignee</th>
<td>unassignedbugs@nondot.org
</td>
</tr>
<tr>
<th>Reporter</th>
<td>cnwy1996@outlook.com
</td>
</tr>
<tr>
<th>CC</th>
<td>llvm-bugs@lists.llvm.org
</td>
</tr></table>
<p>
<div>
<pre>$ clang -v
clang version 11.0.0
Target: x86_64-unknown-linux-gnu
Thread model: posix
InstalledDir: /home/wangyang/llvm-project/build/bin
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/7
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/7.5.0
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/8
Selected GCC installation: /usr/lib/gcc/x86_64-linux-gnu/7.5.0
Candidate multilib: .;@m64
Selected multilib: .;@m64
$ cat test.c
#include<stdio.h>
typedef unsigned int dev_t;
typedef unsigned int kdev_t;
static inline kdev_t to_kdev_t(int dev) {
int major, minor;
if (sizeof(kdev_t) == 16)
return (kdev_t)dev;
major = (dev >> 8);
minor = (dev & 0xff);
return (((major) << 22) | (minor));
}
void do_mknod(const char *filename, int mode, kdev_t dev) {
if (dev == 0x15800078)
exit(0);
else
abort();
}
int sys_mknod(const char *filename, int mode, dev_t dev) {
int error;
char *tmp;
tmp = (char *)((unsigned int)filename*5+1);
error = ((long)(tmp));
do_mknod(tmp, mode, to_kdev_t(dev));
printf("Executed!\n");
return error;
}
int main(void) {
if (sizeof(int) != 4)
exit(0);
return sys_mknod("test", 1, 0x12345678);
}
$ clang -w -O0 -g -fcoverage-mapping -fprofile-instr-generate=test.profraw
test.c; ./a.out; llvm-profdata merge test.profraw -o test.profdata; llvm-cov
show a.out -instr-profile=test.profdata test.c > test.lcov; cat test.lcov
1| |#include<stdio.h>
2| |typedef unsigned int dev_t;
3| |typedef unsigned int kdev_t;
4| |
5| 1|static inline kdev_t to_kdev_t(int dev) {
6| 1| int major, minor;
7| 1|
8| 1| if (sizeof(kdev_t) == 16)
9| 0| return (kdev_t)dev;
10| 1| major = (dev >> 8);
11| 1| minor = (dev & 0xff);
12| 1| return (((major) << 22) | (minor));
13| 1|}
14| |
15| 1|void do_mknod(const char *filename, int mode, kdev_t dev) {
16| 1| if (dev == 0x15800078)
17| 1| exit(0);
18| 0| else
19| 0| abort();
20| 1|}
21| |
22| 1|int sys_mknod(const char *filename, int mode, dev_t dev) {
23| 1| int error;
24| 1| char *tmp;
25| 1|
26| 1| tmp = (char *)((unsigned int)filename*5+1);
27| 1| error = ((long)(tmp));
28| 1| do_mknod(tmp, mode, to_kdev_t(dev));
29| 1| printf("Executed!\n");
30| 1| return error;
31| 1|}
32| |
33| 1|int main(void) {
34| 1| if (sizeof(int) != 4)
35| 0| exit(0);
36| 1|
37| 1| return sys_mknod("test", 1, 0x12345678);
38| 1|}
Line 29 and 30 were not executed.</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>