Type: Debugger
Input information below

Describe the bug

• OS and Version: Microsoft Windows [Version 10.0.18875.1000]
• VS Code Version:

Version: 1.33.1 (user setup)
Commit: 51b0b28134d51361cf996d2f0a1c698247aeabd8
Date: 2019-04-11T08:27:14.102Z
Electron: 3.1.6
Chrome: 66.0.3359.181
Node.js: 10.2.0
V8: 6.6.346.32
OS: Windows_NT x64 10.0.18875

• C/C++ Extension Version:

Name: C/C++
Id: ms-vscode.cpptools
Description: C/C++ IntelliSense, debugging, and code browsing.
Version: 0.22.2-insiders
Publisher: Microsoft
VS Marketplace Link: https://marketplace.visualstudio.com/items?itemName=ms-vscode.cpptools

• Other extensions you installed (and if the issue persists after disabling them): N/A
• A clear and concise description of what the bug is:

Debug configuration could be configured to be slightly more dynamic:

"sourceFileMap": {"/mnt/c": "${env:systemdrive}/"}

To Reproduce
Steps to reproduce the behavior:

1. Open .vscode/launch.json
2. While in C++ Launch/(gdb) Bash on Windows Launch/ configuration scroll down to sourceFileMap
3. replace existing sourceFileMap with improved more dynamic one:

   "sourceFileMap": {
   	"/mnt/c": "${env:systemdrive}/"
   }

4. Unfortunately the /mnt/c could not be optimized further because using $(wslpath $SYSTEMDRIVE/) does not seem to work