即使我没有显示它的路径，windbg也会找到我的应用程序pdb文件

Question

1. I created a simple demo application (app.exe) in default projects folder under my documents.
2. I copied the app.exe to c:\\test\\app folder without copying the pdb file.

I run this executable with windbg (File menu > Open executable). I expect it NOT to find the symbol file but it does!

I set sympath to .sympath srv*c:\\test\\Symbols*https://msdl.microsoft.com/download/symbols

The output for lm is

0:000> lm
start    end        module name
013b0000 013b8000   App      C (private pdb symbols)  c:\users\username\documents\visual studio 2013\Projects\App\Release\App.pdb
0f500000 0f571000   MSVCP120   (private pdb symbols)  c:\test\symbols\msvcp120.i386.pdb\0B631FCA474F4F6FBBE54C497C5821361\msvcp120.i386.pdb
0f740000 0f82e000   MSVCR120   (private pdb symbols)  c:\test\symbols\msvcr120.i386.pdb\16F5E2EF340A453ABC8B8F67DC6FD8082\msvcr120.i386.pdb
76860000 768a7000   KERNELBASE   (pdb symbols)          c:\test\symbols\wkernelbase.pdb\90BA6126FA6340F1ABFAE58DB8B7FB7D1\wkernelbase.pdb
769e0000 76af0000   kernel32   (pdb symbols)          c:\test\symbols\wkernel32.pdb\515F42F53681439D989AC0FC08F7F8F72\wkernel32.pdb
77210000 77390000   ntdll      (pdb symbols)          c:\test\symbols\wntdll.pdb\B5ACAC3B4A6C4515AF416D60366399652\wntdll.pdb

So the executable I am running is in c:\\test\\app\\app.exe , how does it finds its pdb file in my documents folder?

I verified, it is not cached.

Answer 1

Applications contain the path to the PDB file in the executable itself. You can make that visible in various ways:

1. You can verify that eg with Sysinternals Strings utility:

    strings app.exe | findstr ".pdb" 

   will output the full path to the PDB.

2. Another tool (a bit more specific to debugging) to achieve a similar result is DebugDir :

    E:\\[...]\\DebugDir>DebugDir.exe "E:\\[...]\\Reporter.exe" File: E:\\[...]\\Reporter.exe Number of entries in debug directory: 1 Debug directory entry 1: Type: 2 ( CodeView ) TimeStamp: 5772e493 Characteristics: 0 MajorVer: 0 MinorVer: 0 Size: 120 RVA: 000ba482 FileOffset: 000b8682 CodeView format: RSDS Signature: {eac36e37-78c5-47c5-bc95-7c6e5896f694} Age: 1 PdbFile: E:\\[...]\\obj\\Debug\\Reporter.pdb 

3. In WinDbg itself, use !lmi

    0:009> !lmi Reporter [...] Debug Data Dirs: Type Size VA Pointer CODEVIEW 77, 82cf2, 80ef2 RSDS - GUID: {588CF7EE-FA7C-44F9-850C-382520749BE8} Age: 1, Pdb: E:\\[...]\\obj\\Debug\\Reporter.pdb Symbol Type: DEFERRED - No error - symbol load deferred Load Report: no symbols loaded 

   Alternatively, first find out the address of the module and then dump the headers (which is quite verbose).

    0:009> lm m Reporter start end module name 002c0000 00350000 Reporter (deferred) 0:009> !dh 002c0000 [...] Debug Directories(1) Type Size Address Pointer cv 77 82cf2 80ef2 Format: RSDS, guid, 1, E:\\[...]\\obj\\Debug\\Reporter.pdb 

If you don't want the path to be part of your executable, check if there's a compiler/linker setting that turns this feature off, eg /pdbpath:none for the Microsoft Visual C++ compiler.

If you don't want the debugger to find the PDB, move the PDB into a different folder instead of the executable.