diff --git a/cmake/FindPythonCairo.cmake b/cmake/FindPythonCairo.cmake
--- a/cmake/FindPythonCairo.cmake
+++ b/cmake/FindPythonCairo.cmake
@@ -1,6 +1,6 @@
 if(CMAKE_VERSION VERSION_LESS 3.12.0)
     find_package(PythonInterp 3 REQUIRED)
-    set(PYTHON_EXECUTABLE "${Python3_EXECUTABLE}")
+    # PythonInterp sets PYTHON_EXECUTABLE
 else()
     find_package(Python3 COMPONENTS Interpreter REQUIRED)
     set(PYTHON_EXECUTABLE "${Python3_EXECUTABLE}")