sourceFileMap not being applied to compileCommands

[therealkenc]

• OS and Version: Windows 18922
• VS Code Version: 1.36.1
• C/C++ Extension Version: 0.24.0

To reproduce, set up a launch.json with a "sourceFileMap", for example mine looks like:

            "sourceFileMap": {
                "/": "c:/Users/there/msys64/"
            }

Then in c_cpp_properties.json, enable "compileCommands". Mine looks like:

            "compileCommands": "${workspaceFolder}/build/compile_commands.json"

I am getting the following error from IntelliSense.

The build line from compile_commands.json looks like:

{
  "directory": "/home/there/Devel/mintty/build",
  "command": "/usr/bin/cc.exe    -std=gnu99 -include /home/there/Devel/mintty/src/std.h -Wall -Wextra -Wundef -Werror -g   -o src/CMakeFiles/wslterm.dir/winmain.c.o   -c /home/there/Devel/mintty/src/winmain.c",
  "file": "/home/there/Devel/mintty/src/winmain.c"
},

Debugging (breakpoints etc) works fine naturally, because the paths are being mapped okay. But it appears IntelliSense is unable to grok the paths in compile_commands.json, presumably because the path to winmain.c is not being mapped to c:/Users/there/msys64/home.../src. Which of course it isn't, because IntelliSense has no idea that mapping exists in launch.json (nor can it).

I guess the concrete ask is to add a "sourceFileMap" property to c_cpp_properties.json.

Or, I'm "doing it wrong".

[pieandcakes]

I know that the language service today does not query the launch.json for its settings. I'll let them answer as to how to determine where that file is.

[therealkenc]

Thanks Pierson. I had said "nor can it" (with "it" being the language service) above but having slept on it for a few hours I'm thinking maybe (?) the two can be plumbed together after all.

[pieandcakes]

@sean-mcmanus @bobbrow Is there a workaround for what @therealkenc wants?

[sean-mcmanus]

Why does your compile commands contain Linux paths? Bob and I don't know of any workaround. This is not a feature we plan to implement. You would have to write some code to convert the paths yourself.

[therealkenc]

Why does your compile commands contain Linux paths?

Those aren't Linux paths. They're just paths. Paths that need to be mapped. Which is reason existence launch.json's sourceMap.

This is not a feature we plan to implement.

Good to know, thanks.

[bobbrow]

The compile_commands.json format doesn't have any mapping features as far as we know. According to the documentation, all paths need to be absolute or relative to the "directory". @sean-mcmanus and I were trying to understand which build system is generating this seemingly invalid compile_commands.json.

[therealkenc]

The compile_commands.json format doesn't have any mapping features as far as we know.

Path translation is not a function of compile_commands.json. It would be a function of the language server.

The environment I happened to be using is MSYS2. That is a detail not unique to the ask, which is path mapping for any scenario under which a path mapping is required.

GDB has had subsititute-path for since ever. clangd has very recently implemented the same. The previous response from Sean ("this is not a feature we plan to implement [in our language server ]") is understood, is sufficient, and the response given is appreciated. No worries.

[rsvargas]

It would be nice to have something like sourceFileMap for file path translation for when build commands are executed inside a container, as their path roots will be different than the ones seen by vscode.

I'm currently using sed to change the paths, but it needs to be rebuilt every so often.