Add activated_cfg for ccache

[nornagon]

With this missing, ccache was never being added to PATH, and _EMCC_CCACHE wasn't being set.

[sbc100]

CCACHE is not a recognized setting the emscripten config file as far as I can tell.

The valid config settings are listed here: https://github.com/emscripten-core/emscripten/blob/7cdfa8d9f22562e7c08789a5ae29ad9a1025a8e4/tools/config.py#L122-L140 (not the CACHE is unrelated to ccache).

[nornagon]

Ah, should I add a CCACHE setting there then? FWIW, when I made this change locally, it worked fine without adding it to the config.py list.

[sbc100]

This line should add ccache to your PATH. You would need to be sure to include it in your emsdk activate command line though I think.

[nornagon]

Without activated_cfg, this clause causes ccache to not be added to the path:

emsdk/emsdk.py

Lines 1733 to 1735 in c18280c

	activated_cfg = self.activated_config()
	if not activated_cfg:
	return len(deps) > 0

[sbc100]

activated_cfg doesn't have anything to do with the PATH. activated_cfg is used to add things to the emscripten config file. As far as I know ccache has not place in the emscripten config file.

The things that adds to your PATH is activated_path.

[nornagon]

Okay, then it would seem we need to change L1733-L1735 here, as this results in any tool without an activated_cfg and no deps being excluded. ccache is the only tool without an activated_cfg as far as I can tell.

[nornagon]

I think if we change L1735 to return True then this will result in ccache always being active if it's installed? I'm not super familiar with how emsdk works—where is the list of currently activated tools stored?

[sbc100]

Yes, it looks like we can completely remove those lines I think.

I'm not sure why would declare a tool inactive simply because it has no dependencies.

[sbc100]

@juj any idea why these lines exist?