fix #17351

[cooldome]

fix #17351. Initialization of parent struct in C++ appeared only in C++17. https://stackoverflow.com/questions/47333843/using-initializer-list-for-a-struct-with-inheritance

[cooldome]

Looks like CI is using gcc 5.5 which doesn't support required C++ feature. The best option is to upgrade the CI

[cooldome]

If I got it correctly mingw is taken from nim website https://nim-lang.org/download/mingw64.7z. Who has permission to upgrade it?

[Araq]

Who has permission to upgrade it?

Me. What version of mingw should we ship?

[cooldome]

The first gcc version that has the necessary feature is 8.0. https://sourceforge.net/projects/mingw-w64/files/Toolchains%20targetting%20Win64/Personal%20Builds/mingw-builds/8.1.0/threads-win32/seh/x86_64-8.1.0-release-win32-seh-rt_v6-rev0.7z/download should work. Let me test it later today.

[nc-x]

nim with gcc v8 had bugs https://github.com/nim-lang/Nim/issues/9375 no idea if there are still any issues. anyways, is there any reason to not update to latest mingw?

[cooldome]

I have tried gcc 8.1 I have proposed above and I haven't experienced any issues, checked for issues mentioned in #9375 as well. I think it is ok to upgrade.

[cooldome]

If there si objection to gcc 8.1 there is tdm-gcc 9.2 https://jmeubank.github.io/tdm-gcc/articles/2020-03/9.2.0-release. I also had good experience with it but it comes with installer.

[timotheecour]

can you please check whether upgrading C compiler would fix these windows-specific bugs affecting math issues https://github.com/nim-lang/Nim/issues/17017?

[cooldome]

tested, #17017 is not a problem on mingw 8.1

[timotheecour]

tested, #17017 is not a problem on mingw 8.1

great, just to clarify, what's the output you get for:

import math

func c_frexp2(x: cdouble, exponent: var cint): cdouble {.
    importc: "frexp", header: "<math.h>".}

var x = cdouble(-0.0)
var exponent: cint

echo c_frexp2(x, exponent)
echo sqrt(-1.0)
echo gamma(-1.0)

?

it should be:

-0.0
nan
nan

[nc-x]

Even if nim-lang.org/download/mingw64.7z is updated, most people won't get to know that a newer gcc is required for some bug fixes. is the mingw download integrated into choosenim, so that when the nim version is upgraded, newer mingw will be downloaded as well?

[Araq]

The MingW we ship with Nim has been updated. The next release will have it.

[stale[bot]]

This pull request has been automatically marked as stale because it has not had recent activity. If you think it is still a valid PR, please rebase it on the latest devel; otherwise it will be closed. Thank you for your contributions.

[ringabout]

Succeeded by https://github.com/nim-lang/Nim/pull/20407