ci: Add CI test for MSVS 2026 (#5060)

And some minor fixes discovered along the way.

---------

Signed-off-by: Larry Gritz <lg@larrygritz.com>

Author: lgritz

.github/workflows/ci.yml

@@ -686,17 +686,23 @@ jobs:
           - desc: Windows-2022 VS2022
             runner: windows-2022
             nametag: windows-2022
-            vsver: 2022
             generator: "Visual Studio 17 2022"
             python_ver: "3.12"
             ctest_test_timeout: "240"
             setenvs: export OPENIMAGEIO_PYTHON_LOAD_DLLS_FROM_PATH=1
           - desc: Windows-2025 VS2022
             runner: windows-2025
             nametag: windows-2025
-            vsver: 2022
             generator: "Visual Studio 17 2022"
             python_ver: "3.12"
             ctest_test_timeout: "240"
             setenvs: export OPENIMAGEIO_PYTHON_LOAD_DLLS_FROM_PATH=1
             benchmark: 1
+          - desc: Windows-2025 VS2026
+            runner: windows-2025-vs2026
+            nametag: windows-2025-vs2026
+            generator: "Visual Studio 18 2026"
+            python_ver: "3.12"
+            ctest_test_timeout: "240"
+            setenvs: export OPENIMAGEIO_PYTHON_LOAD_DLLS_FROM_PATH=1
+            benchmark: 1

src/build-scripts/build_opencolorio.bash

@@ -19,8 +19,8 @@ OPENCOLORIO_SOURCE_DIR=${OPENCOLORIO_SOURCE_DIR:=${LOCAL_DEPS_DIR}/OpenColorIO}
 OPENCOLORIO_BUILD_DIR=${OPENCOLORIO_BUILD_DIR:=${LOCAL_DEPS_DIR}/OpenColorIO-build}
 OPENCOLORIO_INSTALL_DIR=${OPENCOLORIO_INSTALL_DIR:=${LOCAL_DEPS_DIR}/dist}
 OPENCOLORIO_BUILD_TYPE=${OPENCOLORIO_BUILD_TYPE:=Release}
-OPENCOLORIO_CXX=${OPENCOLORIO_CXX:=g++}
-OPENCOLORIO_CXX_FLAGS=${OPENCOLORIO_CXX_FLAGS:="-Wno-unused-function -Wno-deprecated-declarations -Wno-cast-qual -Wno-write-strings"}
+OPENCOLORIO_CXX=${OPENCOLORIO_CXX:=${CXX}}
+OPENCOLORIO_CXX_FLAGS=${OPENCOLORIO_CXX_FLAGS:=}
 # Just need libs:
 OPENCOLORIO_BUILDOPTS="-DOCIO_BUILD_APPS=OFF -DOCIO_BUILD_NUKE=OFF \
                        -DOCIO_BUILD_DOCS=OFF -DOCIO_BUILD_TESTS=OFF \

src/build-scripts/gh-win-installdeps.bash

@@ -24,18 +24,18 @@ export LD_LIBRARY_PATH="$LD_LIBRARY_PATH:$DEP_DIR/lib:$VCPKG_INSTALLATION_ROOT/i
 #ls -l "C:/Program Files (x86)/Microsoft Visual Studio" && true
 
 
-if [[ "$PYTHON_VERSION" == "3.7" ]] ; then
-    export CMAKE_PREFIX_PATH="$CMAKE_PREFIX_PATH;/c/hostedtoolcache/windows/Python/3.7.9/x64"
-    export Python_EXECUTABLE="/c/hostedtoolcache/windows/Python/3.7.9/x64/python.exe"
-    export PYTHONPATH=$OpenImageIO_ROOT/lib/python${PYTHON_VERSION}/site-packages
-elif [[ "$PYTHON_VERSION" == "3.9" ]] ; then
+if [[ "$PYTHON_VERSION" == "3.9" ]] ; then
     export CMAKE_PREFIX_PATH="$CMAKE_PREFIX_PATH;/c/hostedtoolcache/windows/Python/3.9.13/x64"
     export Python_EXECUTABLE="/c/hostedtoolcache/windows/Python/3.9.13/x64/python3.exe"
     export PYTHONPATH=$OpenImageIO_ROOT/lib/python${PYTHON_VERSION}/site-packages
 elif [[ "$PYTHON_VERSION" == "3.12" ]] ; then
     export CMAKE_PREFIX_PATH="$CMAKE_PREFIX_PATH;/c/hostedtoolcache/windows/Python/3.12.10/x64"
     export Python_EXECUTABLE="/c/hostedtoolcache/windows/Python/3.12.10/x64/python3.exe"
     export PYTHONPATH=$OpenImageIO_ROOT/lib/python${PYTHON_VERSION}/site-packages
+elif [[ "$PYTHON_VERSION" == "3.14" ]] ; then
+    export CMAKE_PREFIX_PATH="$CMAKE_PREFIX_PATH;/c/hostedtoolcache/windows/Python/3.14.3/x64"
+    export Python_EXECUTABLE="/c/hostedtoolcache/windows/Python/3.14.3/x64/python3.exe"
+    export PYTHONPATH=$OpenImageIO_ROOT/lib/python${PYTHON_VERSION}/site-packages
 fi
 pip install numpy
 
@@ -77,6 +77,13 @@ if [[ "$OPENEXR_VERSION" != "" ]] ; then
     # the above line is admittedly sketchy
 fi
 
+echo "OPENCOLORIO_VERSION='${OPENCOLORIO_VERSION}'"
+if [[ "$OPENCOLORIO_VERSION" != "" ]] ; then
+    OPENCOLORIO_INSTALL_DIR=$DEP_DIR
+    source src/build-scripts/build_opencolorio.bash
+    export PATH="$OPENCOLORIO_INSTALL_DIR/bin:$OPENCOLORIO_INSTALL_DIR/lib:$PATH"
+fi
+
 cp $DEP_DIR/lib/*.lib $DEP_DIR/bin || true
 cp $DEP_DIR/bin/*.dll $DEP_DIR/lib || true
 echo "DEP_DIR $DEP_DIR :"

src/cmake/build_expat.cmake

@@ -47,7 +47,7 @@ set (expat_DIR ${expat_ROOT}/lib/cmake/expat-${expat_VERSION})
 if (WIN32)
     # Set the expat_LIBRARY variable to the full path to ${EXPAT_LIBRARIES}.
     # For some reason, find_package(expat) behaves differently on Windows
-    find_package (EXPAT ${expat_BUILD_VERSION} EXACT REQUIRED)
+    find_package (expat ${expat_BUILD_VERSION} EXACT REQUIRED)
     set_cache(expat_LIBRARY ${EXPAT_LIBRARIES} "Full path to the expat library")
     message(STATUS "expat_LIBRARY = ${expat_LIBRARY}")
 endif ()