Dear all, I've been trying to submit a package update, and I found a completely new issue that I'm failing to replicate locally: at https://win-builder.r-project.org/incoming_pretest/EmbedSOM_2.2.1_20260308_225310/Windows/00install.out the builder fails with this error: d:/rtools45/x86_64-w64-mingw32.static.posix/include/sys/types.h:10:2: error: #error Only Win32 target is supported! 10 | #error Only Win32 target is supported! The error is triggered by including a std c++ <thread> header from a .cpp file. As far as I can tell this might be a compiler setup that doesn't support #include<thread> at all. Is there any way to make the threads work on windows? Notably, the source files seem to build right with my local copy of mingw (but that one is likely different from the one used at the build machine.) The package in question is EmbedSOM, source is at https://github.com/exaexa/EmbedSOM . I mirrored the build log to https://pastebin.com/rmePqADD just to be sure it doesn't disappear too early. A skim through the packaging guide didn't reveal any obvious mistake that I'd be doing. Any help or even hints on where to start logging is very welcome. Thanks a lot!
[R-pkg-devel] failure on windows builder ("only Win32 target is supported")
3 messages · Miroslav Kratochvil, Ivan Krylov
Dear Miroslav & Uwe, On Mon, 9 Mar 2026 10:14:31 +0100
Miroslav Kratochvil <exa.exa at gmail.com> wrote:
Here's the strange part:
using C++ compiler: 'g++ (GCC) 15.2.0'
The currently available version of RTools 4.5 only has GCC 14.3 (and compiles EmbedSOM without a problem). Judging by the include paths containing /usr/lib/gcc/x86_64-pc-cygwin/, it might be a %PATH% problem on Win-Builder, with the MSYS/Cygwin toolchain being picked up instead of the desired UCRT one.
Best regards, Ivan
1 day later
Hello, I see that Uwe has re-triggered the build, and now it looks like that all went through just right. Thanks for help to both of you! -mk
On Mon, 9 Mar 2026 at 16:31, Ivan Krylov <ikrylov at disroot.org> wrote:
Dear Miroslav & Uwe, On Mon, 9 Mar 2026 10:14:31 +0100 Miroslav Kratochvil <exa.exa at gmail.com> wrote:
Here's the strange part:
using C++ compiler: 'g++ (GCC) 15.2.0'
The currently available version of RTools 4.5 only has GCC 14.3 (and compiles EmbedSOM without a problem). Judging by the include paths containing /usr/lib/gcc/x86_64-pc-cygwin/, it might be a %PATH% problem on Win-Builder, with the MSYS/Cygwin toolchain being picked up instead of the desired UCRT one. -- Best regards, Ivan