gh-96398: Purge Emscripten code from configure.ac

[erlend-aasland]

See gh-113632 and python/peps#3612: Emscripten is no longer supported

• Issue: configure.ac: using $CC to check compiler names may result in erroneous judgements #96398

[erlend-aasland]

cc. @corona10

[corona10]

What about this change? #117819

[erlend-aasland]

What about this change? #117819

IMO that should remain. We want to filter emcc out in ac_cv_cc_name switches.

[corona10]

#if defined(__EMSCRIPTEN__)
emcc

But this code is no reason to remain if we purge them no?

[erlend-aasland]

#if defined(__EMSCRIPTEN__)
emcc

But this code is no reason to remain if we purge them no?

emcc also defines __clang__ and __GNUC__ :(

[corona10]

Okay, so to filter out emcc, we need emcc :(

Would you like to add a comment on that code to annotate that we do not support each according to PEP?

[erlend-aasland]

Okay, so to filter out emcc, we need emcc :(

Or to put it another way: to filter out emcc, we need to know how to identify it :)

Would you like to add a comment on that code to annotate that we do not support each according to PEP?

We already have the switch in L1130. Did you think about a comment in the check that defines ac_cv_cc_name?

[erlend-aasland]

Alternatively, we can just keep this code; there is not a huge maintenance burden; a solution could be to add a comment above the lines that are proposed to be purged by this PR.

[vstinner]

I don't get why this code has to be removed right now. CPython is full of code specific to "unsupported" platforms such as MinGW or OpenBSD. There are CPython users using this build mode: build CPython for the browser.

[erlend-aasland]

I don't get why this code has to be removed right now. CPython is full of code specific to "unsupported" platforms such as MinGW or OpenBSD. There are CPython users using this build mode: build CPython for the browser.

Yes, let's go with my suggestion from #117836 (comment).

[vstinner]

"CPython in the browser" is a top topic with https://pyodide.org/ and https://pyscript.net/ projects.