Rtools40 msys2 runtime packages
A few core msys2 runtime packages that were altered from upstream msys2 to work better for R and CRAN.
These packages are only needed to build the rtools40 runtime environment itself, regular R users and package developers don't need to be concerned with this at all. The mingw-w64 toolchains and c/c++ libraries for building R and R packages are in the rtools-packages repository.
The Rtools40 runtime consists of subset of msys2 with a few alterations:
- rtools-mirrors replaces
pacman-mirrorswith our custom rtools-packages repos - gnupg uses gpg1 instead of the much heavier gpg2
- curl uses our custom curl-ca-bundle instead of the annoying ca-certificates
- pacman has been rebuild with the above.
- tar has some custom patch from BDR for backward compatibility with old rtools
- texindex-bat MikTeX compatible wrapper for texindex
- libxml2 disabled ICU which doesn't work on CRAN (Because Windows Vista)
- make has a patch to find
shwhen called from cmd instead of bash
For the other msys2 packages in rtools (including dependencies of the above) we use upstream msys2 builds. This means we may need to rebuild our binaries when an upstream dependency has a major upgrades which breaks the dll ABI.
Finally note that pacman is fully statically linked so it has no dll dependencies. Make sure our custom version of curl is installed when building pacman because all curl settings will be hardcoded in pacman.exe.
These binaries are automatically downloaded when building the rtools-installer bundle.