GHA/windows: apply MSYS2 runtime downgrades to v3.5.x, leave v3.6.x as-is

windows-runners 20250420.1.0 come with msys2-runtime 3.6.x. It has
the perf regression issue fixed, so stop downgrading it.

This makes CI jobs settle on this version when supplied by
the runner image or the msys2/setup-msys2 action:
MINGW64_NT-10.0-20348 fv-az980-636 3.6.1-0cfedd4f.x86_64 2025-04-12 01:44 UTC x86_64 Msys

With 3.6.1, we've seen issues launching `perl.exe` before this patch:
https://github.com/curl/curl/discussions/14854#discussioncomment-12908214
https://github.com/curl/curl/discussions/14854#discussioncomment-12921007

Follow-up to b06c12b7248592cf001e621d7cd8dc78a827212b #16574
Closes #17151

diff --git a/.github/workflows/windows.yml b/.github/workflows/windows.yml
index 58c85025093adb7b28e021bc1c81a435377f5163..f75e1c2fd84c9f040ea0f821322ab53e0f7692fa 100644 (file)
--- a/.github/workflows/windows.yml
+++ b/.github/workflows/windows.yml
@@ -349,7 +349,8 @@ jobs:
         timeout-minutes: 2
         # Downgrade to a known good MSYS2 runtime version to avoid the performance regression
         # causing runtests.pl to run at 2-3x reduced speed.
-        run: exec /usr/bin/pacman --noconfirm --noprogressbar --upgrade https://mirror.msys2.org/msys/x86_64/msys2-runtime-3.5.4-8-x86_64.pkg.tar.zst
+        run: |
+          [[ "$(uname -a)" = *' 3.5'* ]] && exec /usr/bin/pacman --noconfirm --noprogressbar --upgrade https://mirror.msys2.org/msys/x86_64/msys2-runtime-3.5.4-8-x86_64.pkg.tar.zst
 
       - name: 'run tests'
         if: ${{ matrix.tflags != 'skipall' && matrix.tflags != 'skiprun' }}
@@ -520,7 +521,8 @@ jobs:
         timeout-minutes: 2
         # Downgrade to a known good MSYS2 runtime version to avoid the performance regression
         # causing runtests.pl to run at 2-3x reduced speed.
-        run: exec /usr/bin/pacman --noconfirm --noprogressbar --upgrade https://mirror.msys2.org/msys/x86_64/msys2-runtime-3.5.4-8-x86_64.pkg.tar.zst
+        run: |
+          [[ "$(uname -a)" = *' 3.5'* ]] && exec /usr/bin/pacman --noconfirm --noprogressbar --upgrade https://mirror.msys2.org/msys/x86_64/msys2-runtime-3.5.4-8-x86_64.pkg.tar.zst
 
       - name: 'run tests'
         if: ${{ matrix.tflags != 'skipall' && matrix.tflags != 'skiprun' }}
@@ -996,7 +998,8 @@ jobs:
         timeout-minutes: 2
         # Downgrade to a known good MSYS2 runtime version to avoid the performance regression
         # causing runtests.pl to run at 2-3x reduced speed.
-        run: exec /usr/bin/pacman --noconfirm --noprogressbar --upgrade https://mirror.msys2.org/msys/x86_64/msys2-runtime-3.5.4-8-x86_64.pkg.tar.zst
+        run: |
+          [[ "$(uname -a)" = *' 3.5'* ]] && exec /usr/bin/pacman --noconfirm --noprogressbar --upgrade https://mirror.msys2.org/msys/x86_64/msys2-runtime-3.5.4-8-x86_64.pkg.tar.zst
 
       - name: 'run tests'
         if: ${{ matrix.tflags != 'skipall' && matrix.tflags != 'skiprun' }}