Deprecate -m32mscoff

[thewilsonator]

It is synonymous with -m32 on Windows and cannot be used for other platforms.

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Testing this PR locally

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dub run digger -- build "master + dmd#13563"

[ljmf00]

Looks good. Perhaps reference #13110 or https://issues.dlang.org/show_bug.cgi?id=18964 somewhere. The other PR is probably old and there should be some cross-referencing to document it. (either on this or the PR I mentioned, I don't know where it fits the best)

[ibuclaw]

Changelog, both the deprecation and the library renaming.

[thewilsonator]

@MoonlightSentinel seems like all tests with a // LINK: directive seem to be still looking for phobos32mscoff.lib, I'm not sure where in tools/d_do_test.d this is coming from. Any ideas?

[MoonlightSentinel]

LINK: just changes whether d_do_test passes -c to dmd when compiling the test

[MoonlightSentinel]

The issue here is the switch from MODEL=32mscoff to MODEL=32 - which causes the makefiles to name Druntime / Phobos as druntime32.lib / phobos32.lib instead of druntime32mscoff.lib / phobos32mscoff.lib

[thewilsonator]

which causes the makefiles to name Druntime / Phobos as druntime32.lib / phobos32.lib

which is the intended outcome.

An example failing command

\path\to\dmd.exe -conf= -m32 -Ifail_compilation -verrors=0 -Icompilable  -odD:\a\1\s\test\test_results\fail_compilation -ofD:\a\1\s\test\test_results\fail_compilation\needspkgmod_0.exe -i=, fail_compilation\needspkgmod.d

envData.model is clearly 32 here which is what it should be. So the only place I can imagine 32mscoff is coming from is the conf, but we explicitly pass -conf= so I don't understand where it is coming from.

[MoonlightSentinel]

which is the intended outcome.

Okay. run.d currently set the LIB environment variable here:

dmd/test/run.d

Line 535 in 843ae86

env["LIB"] = phobosPath ~ ";" ~ environment.get("LIB");

Note that you'll need to change the MODEL in the druntime / phobos workflows as well.

[MoonlightSentinel]

Relevant configuration files that are currently unchanged:

dmd/src/build.d

Lines 308 to 317 in 4c3701d

	enum conf = `[Environment]
	DFLAGS="-I%@P%\..\..\..\..\..\druntime\import" "-I%@P%\..\..\..\..\..\phobos"
	LIB="%@P%\..\..\..\..\..\phobos"
	[Environment64]
	DFLAGS=%DFLAGS% -L/OPT:NOICF
	[Environment32mscoff]
	DFLAGS=%DFLAGS% -L/OPT:NOICF
	`;

and

https://github.com/dlang/dmd/blob/master/ini/windows/bin/sc.ini