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ament_cmake_core/cmake/core/python.cmake

@@ -18,7 +18,16 @@
 #   find_package(Python3 3.8 REQUIRED)
 #   find_package(ament_cmake REQUIRED)
 if(NOT TARGET Python3::Interpreter)
-  if(NOT Python3_EXECUTABLE)
+  # We expect that Python dependencies are met for whatever Python interpreter
+  # is invoked by the "python3" executable, however this may not be the latest
+  # Python version installed on the system. The default behavior of
+  # find_package(Python3) would be to use the latest version, so we
+  # specifically look for a "python3" executable and if found, instruct
+  # find_package(Python3) to use that.
+  # On Windows, the find_package(Python3) logic is different and doesn't
+  # appear to prefer specific versions (i.e. python3.12) over plain
+  # "python.exe" so this extra logic is unnecessary there.
+  if(NOT WIN32 AND NOT Python3_EXECUTABLE)
     find_program(Python3_EXECUTABLE python3)
   endif()
   find_package(Python3 REQUIRED COMPONENTS Interpreter)