Supporting '-skey=value'

[ghost]

There's an issue happening when em++ is run with CMake, that some flags get reduced using the -s option, due to preexisting CMake behavior. For example:

target_compile_options(example PRIVATE -s key1=value -s key2=value)
# Becomes '-s key1=value key2=value

This is documented in the 3.12.4 and up, here. The working around is to use the SHELL syntax, but it causes extra verbosity.

target_compile_options(example PRIVATE "SHELL: -s key1=value -s key2=value")

I'd like to advocate supporting arguments like this:

em++ -skey1=value -skey2=value

I also believe this is related to #5852, which never got resolved.

[sbc100]

Seems like a reasonable request. That duplication feature of cmake seem pretty crazy/risky.

[ghost]

Thanks! Just to be clear, because I forgot to explicitly say it at first, adding support for the abbreviated version would allow these options to be used normally, like this:

# Doesn't reduce
target_compile_options(example PRIVATE -skey1=val -skey2=val)

Internally, CMake uses std::unordered_set, which is what reduces the options.

If I had to guess, they decided to document the behavior instead of break backwards compatibility by changing it.

[apples]

I am also running into this issue.

Regarding CMake, duplicate arguments can be handled with the SHELL: syntax. This is not ideal, and is an annoying hurdle for newcomers. But at least there is a way to deal with it. Lots of things in CMake are "risky" 😅

I am also running into microsoft/vscode-cmake-tools#1350, which is probably just a bug in CMake Tools since it also occurs when using the SHELL: syntax.