Okay, things are not quite working right (and I forgot about shared builds not being available on MinGW-w64). Set up the next round of debugging early, and debug our PowerShell now.

azure-pipelines.yml

@@ -4,34 +4,6 @@ variables:
   releaseExamples: 'controlgallery cpp-multithread datetime drawtext histogram tester timer'
 
 jobs:
-- job: windows_386_mingw_shared
-  displayName: 'Windows 386 MinGW-w64 Shared'
-  pool:
-    vmImage: 'vs2017-win2016'
-  workspace:
-    clean: all
-  steps:
-  - template: azure-pipelines/setup-python3.yml
-  - template: azure-pipelines/install-latest-meson.yml
-  - template: azure-pipelines/windows-install-ninja.yml
-  - template: azure-pipelines/windows-setup-mingw.yml
-    parameters:
-      which: mingw32
-  - template: azure-pipelines/configure.yml
-    parameters:
-      defaultLibrary: shared
-  - template: azure-pipelines/build.yml
-    parameters:
-      afterBuild: dir build\meson-out
-#  - template: azure-pipelines/windows-artifacts.yml
-#    parameters:
-#      os: windows
-#      arch: 386
-#      toolchain: mingw
-#      libtype: shared
-#      libfiles: libui.dll
-#      osHeader: ui_windows.h
-
 - job: windows_386_mingw_static
   displayName: 'Windows 386 MinGW-w64 Static'
   pool:
@@ -60,3 +32,32 @@ jobs:
 #      libtype: static
 #      libfiles: libui.lib
 #      osHeader: ui_windows.h
+
+- job: windows_amd64_mingw_static
+  displayName: 'Windows amd64 MinGW-w64 Static'
+  pool:
+    vmImage: 'vs2017-win2016'
+  workspace:
+    clean: all
+  steps:
+  - template: azure-pipelines/setup-python3.yml
+  - template: azure-pipelines/install-latest-meson.yml
+  - template: azure-pipelines/windows-install-ninja.yml
+  - template: azure-pipelines/windows-setup-mingw.yml
+    parameters:
+      which: mingw64
+  - template: azure-pipelines/configure.yml
+    parameters:
+      defaultLibrary: static
+  - template: azure-pipelines/build.yml
+    parameters:
+      afterBuild: dir build\meson-out
+#      afterBuild: ren build\meson-out\libui.a libui.lib
+#  - template: azure-pipelines/windows-artifacts.yml
+#    parameters:
+#      os: windows
+#      arch: amd64
+#      toolchain: mingw
+#      libtype: static
+#      libfiles: libui.lib
+#      osHeader: ui_windows.h

azure-pipelines/build.yml

@@ -7,6 +7,6 @@ parameters:
 steps:
 - script: |
     ${{ parameters.beforeBuild }}
-    ninja -C build
+    ninja -C build -v
     ${{ parameters.afterBuild }}
   displayName: 'Build'

azure-pipelines/windows-setup-mingw.yml

@@ -8,5 +8,6 @@ steps:
     $chocopath = where.exe choco.exe | Get-Item
     # apparently they didn't think to add this functionality from the start (multiple joins was only added in PowerShell 6 and Azure Pipelines is using 5.x), and the direct-CLR approach actually behaves differently (and I would need to check which version of .net Azure Pipelines is using anyway, since our use case isn't one of those cases where it behaves differently)
     $chocopath = Join-Path -Path $chocopath.Directory -ChildPath "install" | Join-Path -ChildPath "${{ parameters.which }}" | Join-Path -ChildPath "bin"
-    echo "##vso[task.prependpath]$chocopath"
+    echo "abcdef##vso[task.prependpath]$chocopath"
+    exit 1
   displayName: 'Set Up MinGW-w64'