Improve finding Python library/includes (#8718)

On macOS, find_package(PythonLibs ...) does not find the Python
include directory or library when they were installed via homebrew.
find_package(Python ...) is more robust, but only available on newer
versions of CMake. If we are compiling cvc5 on macOS and we have a newer
version of CMake available, this tries to use find_package(Python ...)
to find the paths.

diff --git a/src/api/python/CMakeLists.txt b/src/api/python/CMakeLists.txt
index b5c7b917b88ce2fce85fd3aa5dc4b4dd140962e5..eb9d6ec311eb95cb062bbd3f287042d7f1b6f977 100644 (file)
--- a/src/api/python/CMakeLists.txt
+++ b/src/api/python/CMakeLists.txt
@@ -44,6 +44,20 @@ endif()
 list(APPEND CMAKE_MODULE_PATH ${SKBUILD_CMAKE_MODULE_PATH})
 
 find_package(PythonExtensions REQUIRED)
+
+if(CMAKE_SYSTEM_NAME STREQUAL "Darwin" AND
+   CMAKE_VERSION VERSION_GREATER_EQUAL "3.12")
+  # On macOS, find_package(PythonLibs ...) does not find the Python include
+  # directory or library when they were installed via homebrew.
+  # find_package(Python ...) is more robust, but only available on newer
+  # versions of CMake. If we are compiling cvc5 on macOS and we have a newer
+  # version of CMake available, we try to use find_package(Python ...) to find
+  # the paths.
+  find_package(Python COMPONENTS Development)
+  set(PYTHON_INCLUDE_DIRS "${Python_INCLUDE_DIRS}")
+  set(PYTHON_LIBRARY "${Python_LIBRARIES}")
+endif()
+
 find_package(Cython 0.29 REQUIRED)
 
 set(CYTHON_FLAGS "-X embedsignature=True")