<div dir="ltr">Hi,<div><br></div><div style>I am new to lldb and creating a patch to support Linux coredumps.</div><div style>This plugin is based on mach-core plugin.</div><div style>Currently it can parss the NOTE segments and loads all the threads found in the corefile(x86_64).</div>
<div style>That is "thread list" works fine.</div><div style><br></div><div style>It also reads the PRSTATUS structure and populates the register infromation.</div><div style>That is "register read" works fine.</div>
<div style><br></div><div style>However lldb is not using the symbol files while using the core file. Because of this it is not using DWARF structures while creating frames. That is frame variables and arguments are not available. Also lldb not resolving address to symbols.<br>
</div><div style><br></div><div style><div>$lldb</div><div>(lldb) target create -c ./core</div><div>Core file '/mts/home3/jacobs/test/core' (x86_64) was loaded.</div><div>Process 0 stopped</div><div>* thread #1: tid = 0x0000, 0x00000000004004c4, stop reason = signal SIGCONT</div>
<div> frame #0: 0x00000000004004c4</div><div>error: core file does not contain 0x4004c4</div><div>(lldb) target modules add ./a.out</div><div>(lldb) image lookup --address 0x4004c4</div><div> Address: a.out[0x00000000004004c4] (a.out..text + 244)</div>
<div> Summary: a.out`function4 + 16 at test.c:4</div><div>(lldb) bt</div><div>* thread #1: tid = 0x0000, 0x00000000004004c4, stop reason = signal SIGCONT</div><div> frame #0: 0x00000000004004c4</div><div> frame #1: 0x00000000004004d7</div>
<div> frame #2: 0x00000000004004e7</div><div> frame #3: 0x00000000004004f7</div><div> frame #4: 0x0000000000400507</div><div>(lldb) image lookup --address 0x00000000004004d7</div><div> Address: a.out[0x00000000004004d7] (a.out..text + 263)</div>
<div> Summary: a.out`function3 + 11 at test.c:8</div><div><br></div></div><div style>In the above example the IP's are not resolved to symbol in "bt" although lldb is able to resolve the addresses using "image lookukp" . What command should be used to link a target with symbol file?</div>
<div style><br></div><div style>Here is the program that I used which compiled with "gcc -O0 -g3"<br></div><div style><div>$cat test.c</div><div>void function4(unsigned int arg)</div><div>{</div><div> char *local = 0;</div>
<div> *local = 0;</div><div>}</div><div>void function3()</div><div>{</div><div> function4(-1);</div><div>}</div><div>void function2(long arg)</div><div>{</div><div> function3();</div><div>}</div><div>void function1(int arg1, long arg2, char *str)</div>
<div>{</div><div> function2(1);</div><div>}</div><div>void main()</div><div>{</div><div> function1(0, 1L, "Test\n");</div><div>}</div><div><br></div><div style>GDB output</div><div style><br></div><div style>
<div>$gdb --quiet a.out core</div><div>Reading symbols from /mts/home3/jacobs/test/a.out...done.</div><div><br></div><div>warning: exec file is newer than core file.</div><div>[New LWP 26718]</div><div><br></div><div>warning: Can't read pathname for load map: Input/output error.</div>
<div>Core was generated by `./a.out'.</div><div>Program terminated with signal 11, Segmentation fault.</div><div>#0 0x00000000004004c4 in function4 (arg=0) at test.c:4</div><div>4 *local = 0;</div><div>(gdb) bt</div>
<div>#0 0x00000000004004c4 in function4 (arg=0) at test.c:4</div><div>#1 0x00000000004004d7 in function3 () at test.c:8</div><div>#2 0x00000000004004e7 in function2 (arg=4195559) at test.c:11</div><div>#3 0x00000000004004f7 in function1 (arg1=0, arg2=140736328348032, str=0x4004e7 <incomplete sequence \370\270>) at test.c:15</div>
<div>#4 0x0000000000400507 in function1 (arg1=0, arg2=140736328348048, str=0x4004f7 "\345H\203\354\030\211}\374H\211u\360H\211U\350\277\001") at test.c:15</div><div>#5 0x00007fbcdfe6c76d in __libc_start_main () from /lib/x86_64-linux-gnu/libc.so.6</div>
<div>#6 0x00000000004003f9 in _start ()</div><div><br></div><div style>I can post the patch if anyone interested(but it needs to be cleaned up).</div></div></div><div style><br></div><div style>Thanks</div><div style>Samuel </div>
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