Enable linker optimizations when needed on windows

[ryuukk]

This significantly reduce the executable file size

And this is what LDC is doing: https://github.com/ldc-developers/ldc/blob/3b9665bac69df0c27bc1888cca8a442df656d948/driver/linker-msvc.cpp#L130

Discussion: https://forum.dlang.org/post/dcbqjmaqjpdgylpykvab@forum.dlang.org

[dlang-bot]

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Testing this PR locally

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dub run digger -- build "master + dmd#14418"

[ryuukk]

I don't know if that PR is valid, if it is not, then please make appropriate changes, i'm not willing to dive deeper into DMD code base, i don't have the time

[ryuukk]

As per review, i removed the dead code, even though i believe it was needed, but i lack skills so that's a story for an other PR

[maxhaton]

I'll show you how in a few hours

[RazvanN7]

This seems to fail 2 tests on Windows. The failures are linker errors.

[RazvanN7]

@ryuukk any progress on this?

[ryuukk]

I can't run the test myself since the instruction on the wiki doesn't work, it's outdated

https://wiki.dlang.org/Building_under_Windows#Using_DigitalMars_make_for_running_the_test_suite

If one could update the instructions, that would be nice (make related, wich one exactly to get, and from where)

I tried this: https://sourceforge.net/projects/gnuwin32/ but it doesn't work

make.exe: error while loading shared libraries: ?: cannot open shared object file: No such file or directory

[RazvanN7]

Indeed the instructions are outdated. However, both for building the compiler and running the tests we now have d scripts.

I don't have a windows machine, but I expect that if you run the run.d script from compiler/test directory that should run the tests. You can pass a specific directory to the program or a specific test:

run.exe fail_compilation              -> will run all fail compilation tests
run.exe fail_compilation/test123456.d -> will run that specific test

[ryuukk]

It's time for me to quit