<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 - Regression: JITed Code Debugging Broken on LLDB 6.0 Release Branch"
href="https://bugs.llvm.org/show_bug.cgi?id=36209">36209</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>Regression: JITed Code Debugging Broken on LLDB 6.0 Release Branch
</td>
</tr>
<tr>
<th>Product</th>
<td>lldb
</td>
</tr>
<tr>
<th>Version</th>
<td>6.0
</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>All Bugs
</td>
</tr>
<tr>
<th>Assignee</th>
<td>lldb-dev@lists.llvm.org
</td>
</tr>
<tr>
<th>Reporter</th>
<td>stefan.graenitz@gmail.com
</td>
</tr>
<tr>
<th>CC</th>
<td>llvm-bugs@lists.llvm.org
</td>
</tr></table>
<p>
<div>
<pre>Created <span class=""><a href="attachment.cgi?id=19797" name="attach_19797" title="Full logs from LLDB 6.0, LLDB 5.0 and LLDB 4.0">attachment 19797</a> <a href="attachment.cgi?id=19797&action=edit" title="Full logs from LLDB 6.0, LLDB 5.0 and LLDB 4.0">[details]</a></span>
Full logs from LLDB 6.0, LLDB 5.0 and LLDB 4.0
With LLDB built from branch release_60 it is no longer possible to set a
breakpoint in JIT-compiled code. This worked well for release_50. LLDB 6.0
fails with error message:
warning: failed to set breakpoint site at 0x4 for breakpoint 1.1: error: 2
sending the breakpoint request
Repro with a default configuration of LLVM/Clang/LLDB on Linux Mint 18:
$ cat hellow.cpp
#include <stdio.h>
void jitbp() {
printf("Hello World!\n");
}
int main() {
jitbp();
return 0;
}
$ clang -g -c -S -emit-llvm hellow.cpp
$ ./lli hellow.ll
Hello World!
$ ./lldb -- lli
(lldb) target create "lli"
Current executable set to 'lli' (x86_64).
(lldb) b jitbp
Breakpoint 1: no locations (pending).
WARNING: Unable to resolve breakpoint to any actual locations.
(lldb) log enable lldb jit
(lldb) r hellow.ll
Actual output with LLDB 6.0:
lldb JITLoaderGDB::SetJITBreakpoint looking for JIT register hook
lldb JITLoaderGDB::SetJITBreakpoint looking for JIT register hook
Process 17664 launched: '/media/LLVM/llvm60/build-debug-clang-lld-lldb/bin/lli'
(x86_64)
intern-state JITLoaderGDB::SetJITBreakpoint looking for JIT register hook
...
intern-state JITLoaderGDB::SetJITBreakpoint looking for JIT register hook
intern-state JITLoaderGDB::SetJITBreakpoint setting JIT breakpoint
intern-state JITLoaderGDB::JITDebugBreakpointHit hit JIT breakpoint
intern-state JITLoaderGDB::ReadJITDescriptorImpl registering JIT entry at
0x781230 (3432 bytes)
warning: failed to set breakpoint site at 0x4 for breakpoint 1.1: error: 2
sending the breakpoint request
1 location added to breakpoint 1
warning: failed to set breakpoint site at 0x4 for breakpoint 1.1: error: 2
sending the breakpoint request
Hello World!
intern-state JITLoaderGDB::JITDebugBreakpointHit hit JIT breakpoint
intern-state JITLoaderGDB::ReadJITDescriptorImpl unregistering JIT entry at
0x781230
Process 17664 exited with status = 0 (0x00000000)
(lldb) q
Expected output, tested with LLDB 5.0 and LLDB 4.0:
JITLoaderGDB::SetJITBreakpoint looking for JIT register hook
JITLoaderGDB::SetJITBreakpoint looking for JIT register hook
Process 16807 launched: '/media/LLVM/llvm50/build-debug-clang-lld-lldb/bin/lli'
(x86_64)
JITLoaderGDB::SetJITBreakpoint looking for JIT register hook
...
JITLoaderGDB::SetJITBreakpoint looking for JIT register hook
JITLoaderGDB::SetJITBreakpoint setting JIT breakpoint
JITLoaderGDB::JITDebugBreakpointHit hit JIT breakpoint
JITLoaderGDB::ReadJITDescriptorImpl registering JIT entry at 0x754850 (3432
bytes)
1 location added to breakpoint 1
Process 16807 stopped
* thread #1, name = 'lli', stop reason = breakpoint 1.1
frame #0: 0x00007ffff7fee004 JIT(0x754850)`jitbp() at hellow.cpp:4
1 #include <stdio.h>
2
3 void jitbp() {
-> 4 printf("Hello World!\n");
5 }
6
7 int main() {
(lldb) n
Hello World!
Process 16807 stopped
* thread #1, name = 'lli', stop reason = step over
frame #0: 0x00007ffff7fee01c JIT(0x754850)`jitbp() at hellow.cpp:5
2
3 void jitbp() {
4 printf("Hello World!\n");
-> 5 }
6
7 int main() {
8 jitbp();
(lldb) c
Process 16807 resuming
JITLoaderGDB::JITDebugBreakpointHit hit JIT breakpoint
JITLoaderGDB::ReadJITDescriptorImpl unregistering JIT entry at 0x754850
Process 16807 exited with status = 0 (0x00000000)
(lldb) q
The same issue can be reproduced with a slightly modified version of LLDB that
allows debugging JITed code on Mac OS X. Please find attached the full logs.</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>