This is a compiler bug. 

> On Oct 14, 2016, at 12:14 PM, Ted Woodward <ted.woodw...@codeaurora.org> 
> wrote:
> 
>> Probably a debug info problem. Before we know to look for addresses within
>> a compile unit, the compile unit must claim it has a function that contains 
>> this
>> address. So check the DWARF in the compile unit that contains 0x114720 (not
>> sure if there is a lookup by address in llmv-dwarfdump?) and make sure
>> there is a DW_TAG_subprogram that contains this address.
>> 
>> Greg
> 
> I'm changing gears here - I'm having the same issue with lldb-server, and 
> it's smaller, so I'm looking at that.
> 
> main calls main_gdbserver, which is in tools/lldb-server/lldb-gdbserver.cpp, 
> and has no line table info, according to lldb's list comm info.
> 
> 4: name = 'main_gdbserver', locations = 2
>  4.1: where = lldb-server`main_gdbserver(int, char**) + 32, address = 
> 0x00048964, unresolved, hit count = 0
>  4.2: where = lldb-server`main_gdbserver(int, char**) + 32, address = 
> 0x00048964, unresolved, hit count = 0
> 
> (lldb) list 0x48964
> error: address resolves to lldb-server[0x0000000000048964], but there is no 
> line table information available for this address.
> 
> 
> main_gdbserver has a DW_AT_subprogram entry:
> 0x000306a4:   DW_TAG_subprogram [106] *
>                DW_AT_low_pc [DW_FORM_addr]    (0x0000000000048944)
>                DW_AT_high_pc [DW_FORM_data4]  (0x00000da4)
>                DW_AT_frame_base [DW_FORM_exprloc]     (<0x1> 6e )
>                DW_AT_linkage_name [DW_FORM_strp]      ( 
> .debug_str[0x0006577b] = "_Z14main_gdbserveriPPc")
>                DW_AT_name [DW_FORM_strp]      ( .debug_str[0x00065792] = 
> "main_gdbserver")
>                DW_AT_decl_file [DW_FORM_data1]        
> ("/local/mnt/workspace/ted/linux/llvm/tools/lldb/tools/lldb-server/lldb-gdbserver.cpp")
>                DW_AT_decl_line [DW_FORM_data2]        (326)
>                DW_AT_type [DW_FORM_ref4]      (cu + 0x003b => {0x00011c13})
>                DW_AT_external [DW_FORM_flag_present]  (true)
> 
> And a linetable entry:
> 0x0000000000048944    327      0      1   0             0  is_stmt
> 0x0000000000048964    328    11      1   0             0  is_stmt prologue_end
> 
> 
> 
> --
> Qualcomm Innovation Center, Inc.
> The Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a 
> Linux Foundation Collaborative Project
> 
>> -----Original Message-----
>> From: Greg Clayton [mailto:gclay...@apple.com]
>> Sent: Tuesday, October 11, 2016 1:34 PM
>> To: Ted Woodward <ted.woodw...@codeaurora.org>
>> Cc: LLDB <lldb-dev@lists.llvm.org>
>> Subject: Re: [lldb-dev] LLDB can't find source...but it can?
>> 
>> 
>>> On Oct 7, 2016, at 4:53 PM, Ted Woodward via lldb-dev <lldb-
>> d...@lists.llvm.org> wrote:
>>> 
>>> Background – I’m working on getting LLDB to run on Hexagon Linux, built
>> with an LLVM toolchain. We’re using libc++ and MUSL. The loader is a bit
>> squirrelly right now, so I’ve built LLDB statically.
>>> 
>>> I’ve got full source debugging in the driver, but when I step into
>> SBDebugger::Create, I don’t have any source. I’ve got symbols:
>>> (lldb) bt
>>> * thread #1: tid = 1, 0x00114730 lldb`lldb::SBDebugger::Create(bool) + 16,
>> stop reason = breakpoint 2.1
>>>  * frame #0: 0x00114730 lldb`lldb::SBDebugger::Create(bool) + 16
>>>    frame #1: 0x000001dc lldb`Driver::Driver(this=0x7ffefc50) + 124 at
>> Driver.cpp:150
>>>    frame #2: 0x00006aa0 lldb`main(argc=1, argv=0x7ffefd34) + 240 at
>> Driver.cpp:1350
>>>    frame #3: 0x04744384 lldb`__libc_start_main + 48
>>> 
>>> list SBDebugger::Create fails, but list SBDebugger::Create(bool) gives me
>> source.
>>> (lldb) list SBDebugger::Create
>>> (lldb) list SBDebugger::Create(bool)
>>> File:
>> \local\mnt\workspace\ted\linux\llvm\tools\lldb\source\API\SBDebugger.cp
>> p
>>>   172      return SBDebugger::Create(false, nullptr, nullptr);
>>>   173  }
>>>   174
>>>   175  SBDebugger
>>>   176  SBDebugger::Create(bool source_init_files)
>>>   177  {
>>>   178      return SBDebugger::Create (source_init_files, nullptr, nullptr);
>>>   179  }
>>>   180
>>>   181  SBDebugger
>>>   182  SBDebugger::Create(bool source_init_files, lldb::LogOutputCallback
>> callback, void *baton)
>>>   183
>>> 
>>> Finally, I try to list based on the address of the function:
>>> (lldb) list 0x114720
>>> error: address resolves to lldb[0x0000000000114720], but there is no line
>> table information available for this address.
>>> 
>>> But there is line table information for 0x114720 (from llvm-dwarfdump):
>>> 0x0000000000114720    177      0     80   0             0  is_stmt
>>> 0x0000000000114730    178     32     80   0             0  is_stmt 
>>> prologue_end
>>> 0x0000000000114734    178     12     80   0             0
>>> 0x0000000000114754    178      5     80   0             0
>>> 
>>> 
>>> 
>>> My breakpoint at SBDebugger::Create resolved to prologue_end:
>>> (lldb) break list
>>> Current breakpoints:
>>> 1: name = 'main', locations = 1, resolved = 1, hit count = 1
>>>  1.1: where = lldb`main + 32 at Driver.cpp:1335, address = 0x000069d0,
>> resolved, hit count = 1
>>> 
>>> 2: name = 'SBDebugger::Create', locations = 3, resolved = 3, hit count = 1
>>>  2.1: where = lldb`lldb::SBDebugger::Create(bool) + 16, address =
>> 0x00114730, resolved, hit count = 1
>>>  2.2: where = lldb`lldb::SBDebugger::Create() + 8, address = 0x001143c0,
>> resolved, hit count = 0
>>>  2.3: where = lldb`lldb::SBDebugger::Create(bool, void (*)(char const*,
>> void*), void*) + 40, address = 0x00114404, resolved, hit count = 0
>>> 
>>> 
>>> So – why can LLDB find the source when I specify the function explicitly, or
>> find the line table info when I set a breakpoint, but not when I am in the
>> function or list an address?
>>> 
>> 
>> 
>>> Ted
>>> 
>>> --
>>> Qualcomm Innovation Center, Inc.
>>> The Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
>> a Linux Foundation Collaborative Project
>>> 
>>> _______________________________________________
>>> lldb-dev mailing list
>>> lldb-dev@lists.llvm.org
>>> http://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-dev
> 
> 

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