revert back to rtools40

Author: thisisnic

.github/workflows/r.yml

@@ -205,7 +205,7 @@ jobs:
       fail-fast: false
       matrix:
         config:
-        - { rtools: 42, arch: 'ucrt64' }
+        - { rtools: 40, arch: 'ucrt64' }
     steps:
       - run: git config --global core.autocrlf false
       - name: Checkout Arrow
@@ -228,10 +228,10 @@ jobs:
             r-${{ matrix.config.rtools }}-ccache-mingw-${{ matrix.config.arch }}-
       - uses: r-lib/actions/setup-r@v2
         with:
-          # Note: RTools must be 42 here because RTools42 + ucrt is how we build the Arrow C++
-          # static library. The R is not used here but R 4.2 was the last R to use
-          # Rtools42.
-          r-version: "4.2"
+          # Note: RTools must be 40 here because RTools40 + ucrt is how we build the Arrow C++
+          # static library. The R is not used here but R 4.1 was the last R to use
+          # Rtools40.
+          r-version: "4.1"
           rtools-version: ${{ matrix.config.rtools }}
           Ncpus: 2
       - name: Build Arrow C++
@@ -284,14 +284,14 @@ jobs:
       - name: Download Timezone Database
         shell: bash
         run: |
-          # MinGW (non-MSVC) builds use the vendored date library for timezone
-          # handling, which requires a local copy of the IANA tzdata database.
+          # RTools 40 uses GCC 8.x which does not support C++20 chrono timezones,
+          # so Arrow uses the vendored date library which requires tzdata
           ci/scripts/download_tz_database.sh
       - run: mkdir r/windows
       - name: Download artifacts
         uses: actions/download-artifact@v8
         with:
-          name: libarrow-rtools42-ucrt64.zip
+          name: libarrow-rtools40-ucrt64.zip
           path: r/windows
       - name: Unzip and rezip libarrows
         shell: bash

ci/scripts/r_windows_build.sh

@@ -23,26 +23,8 @@ set -ex
 # Make sure it is absolute and exported
 export ARROW_HOME="$(cd "${ARROW_HOME}" && pwd)"
 
-# The RTools42 release (r-hub/rtools42) ships with 0-byte ca-bundle.crt files
-# due to an MSYS2 build bug (msys2/msys2-installer#40). Regenerate them from
-# the trust anchors that are already installed.
-if [ ! -s /usr/ssl/certs/ca-bundle.crt ]; then
-  update-ca-trust
-fi
-
-# The CI shell runs bash directly without --login, so MSYSTEM is unset and
-# the ucrt64 toolchain isn't on PATH. Both are needed for makepkg-mingw.
-export MSYSTEM=${MSYSTEM:-UCRT64}
-export PATH="/${MSYSTEM,,}/bin:$PATH"
-
-# RTools42's frozen MSYS2 keyring is too old for current mirror signatures.
-pacman-key --init
-pacman-key --populate msys2
 pacman --noconfirm -Syy
 
-# RTools42's ucrt64 toolchain doesn't include strip; install it for makepkg-mingw.
-pacman --noconfirm -S mingw-w64-ucrt-x86_64-binutils
-
 RWINLIB_LIB_DIR="lib"
 : ${MINGW_ARCH:="mingw32 mingw64 ucrt64"}
 
@@ -64,8 +46,8 @@ cd build
 # This may vary by system/CI provider
 MSYS_LIB_DIR="/c/rtools${RTOOLS_VERSION}"
 
-# Untar the builds we made (RTools42+ uses zstd compression instead of xz)
-ls *.zst *.xz 2>/dev/null | xargs -n 1 tar -xf
+# Untar the builds we made
+ls *.xz | xargs -n 1 tar -xJf
 mkdir -p $DST_DIR
 # Grab the headers from one, either one is fine
 # (if we're building twice to combine old and new toolchains, this may already exist)