[Bazel] [Potential solution] Cannot build multiple emscripten binaries in parallel with bazel

[kalmard0]

On bazel with sandboxing disabled (or when not available, e.g. Windows), multiple parallel binaries will fail to build due to a shared file being written by the compiler: tmp.tar.

This filename comes from

emsdk/bazel/emscripten_toolchain/link_wrapper.py

Line 162 in ce74ca2

cmd = ['tar', 'cf', 'tmp.tar'] + files

I believe this can be easily solved by changing tmp.tar to a filename that includes the current build rule's name, to make it unique. But I haven't managed to test this.

[walkingeyerobot]

That sounds like a reasonable solution. I'm happy to accept a PR that renames tmp.tar.