CDB loads variables very slowly in Qt Creator

Question

I have tried a lots of advice to help to set up the CDB debugger in Qt Creator but when using it that thing still takes ages to load up local variables.

My setup:

• Windows 10 64-bit
• Qt 5.6 (installed with sources)
• Qt Creator 3.6.1
• Microsoft Visual Studio 14 (2015) (both 32-bit and 64-bit compilers)
• Windows SDK (for debugging tools = CDB)

The General tab in Options->Debugging lists auto-detected sources:

Source: Q:/qt5_workdir/w/s
Target: C:\Qt\5.6\Src

My symbols server and cache are set up in CDB Paths like this:

srv*http://msdl.microsoft.com/download/symbols
cache*C:\Qt\CDB-symbols-cache

On first run of the debugger it populates this directory with 70mb of (presumably downloaded) data but it does not seem to change afterwards on subsequent runs.

I suspect either the sources being loaded takes a long time (although I have a SSD) or that the CDB is re-downloading the symbols instead of using the cache. Any advice?

EDIT: As per request, result of .sympath command on my system:

Symbol search path is: srv*

Expanded Symbol search path is: cache*;SRV*https://msdl.microsoft.com/download/symbols

************* Symbol Path validation summary **************

Response Time (ms) Location

Deferred
srv*

Answer 1

I had the same problem with QtCreator 4.12 which was solved by removing AppData\Roaming\QtProject\default.qws as suggested by Abstraction in the comments above.