Sourcemap absolute path issue

[dwz8]

Please include the following in your bug report:

Version of emscripten/emsdk:
Please include the output emcc -v here
emcc (Emscripten gcc/clang-like replacement + linker emulating GNU ld) 3.1.32 (eab98ad)
clang version 17.0.0 (https://github.com/llvm/llvm-project df82394e7a2d06506718cafa347bf7827c79fc4f)
Target: wasm32-unknown-emscripten
Thread model: posix
InstalledDir: C:\Users\diete\emsdk\upstream\bin

emscripten is installed on drive C:
the project is installed on drive D:
sourcemap entries point correctly to relative paths on D:
sourcemap entries use an unusable absolute path for emscripten related files

Test project including a simple sourcemap:
https://github.com/dwz8/emtest

[sbc100]

To be clear, this issue also occurs if emscripten and the project are on the same drive right?

You mentioned on the mailing list that the source map contained a path that looked like: myArea/myApp/C:/Users/myName/emsdk/upstream/emscripten.

It seems like that both is simply broken, regardless of which drive emsdk is on. Or is it the cast that these bad paths are not generated when emsdk is on the same drive as the project?

[dwz8]

If emscripten and the project are on the same drive, the source will contain relative paths to the emscripten files:

{"version":3,"sources":["test.c","../Users/diete/emsdk/upstream/emscripten/system/lib/libc/emscripten_get_heap_size.c","...

So it looks as if the bad paths are only generated when emsdk and project reside on different drives.

[sbc100]

What does that emscripten_get_heap_size.c line looks like in the broken source map?

[dwz8]

{"version":3,"sources":["test.c","C:/Users/diete/emsdk/upstream/emscripten/system/lib/libc/emscripten_get_heap_size.c","C:/Users/diete/emsdk...

[sbc100]

That looks correct to me. Do you know where the bad path (myArea/myApp/C:/Users/myName/emsdk/upstream/emscripten) path in your original report comes from?

[dwz8]

C:/Users/myName/emsdk/upstream/emscripten is the correct installation path on my computer. The map file has of course been generated by emsdk.
The issue may be that localhost can not manage any references across local drives. So localhost (or any other server) can only find the emsdk files if they are in the same "myArea" tree as the source files I think.

[sbc100]

I'm not sure what you mean by "localhost" here. Are you referring to the http server you are using to serve your source files? If its asked to serve C:/Users/myName/emsdk/upstream/emscripten what can't it do that? Is there some fundamental reason? Is there any other solution you can imagine other than fixing the server here?

[dwz8]

sorry for the confusion.
For testing purposes I have Internet Information Server running on my computer. If I launch the project in a browser the URL will be http://localhost/myArea/myApp, because the default directory is set to D:\myArea.
emsdk produces the sourcemap with relative paths for my source files, which is correct. The paths to emsdk files can't be relative (and could never be unless emsdk is installed on the same drive), so it uses the local file path, which can't work.

So either it is a prerequisite to keep emsdk and all projects on the same drive, or another way must be found so that the browser can find the emsdk files. For local testing as in my use case the local file path may suffice if the browser is able to use it.

[sbc100]

so it uses the local file path, which can't work.

Why do you say it cannot work? Its seems like a limitation of the server "Internet Information Server"? Perhaps it is configurable or perhaps you could try a different server that does support absolute paths somehow?

It seems like either you need to find or configure as server that allows absolute paths, or you need to put emsdk in a place where it can be found using a relative path. I'm not sure this is something that can be fixed on the emscripten side.

[dwz8]

Thanks for the suggestion, I will have a look at that.
Chrome turns the absolute path in the map into
file:myArea/myApp/C:/Users/diete/emsdk/upstream/emscripten
So perhaps the issue is there. I will examine this further.
Thanks for your attention!

[sbc100]

Thanks for the suggestion, I will have a look at that. Chrome turns the absolute path in the map into file:myArea/myApp/C:/Users/diete/emsdk/upstream/emscripten

Oh I see.. that does seem wrong. So in that case no request is actually being sent to the server? That seems pretty strange.

[dwz8]

I just ran the project in Firefox. It seems to sort out the absolute path correctly, however, when accessing the source file I see an error:
unsupported protocol for sourcemap request c:/Users/diete/emsdk/upstream/emscripten/system/lib/dlmalloc.c