support older CMake

ginkgo-project · May 21, 2023 · df98da7 · df98da7
1 parent b5aff96
commit df98da7
Showing 1 changed file with 5 additions and 1 deletion.
diff --git a/third_party/nlohmann_json/CMakeLists.txt b/third_party/nlohmann_json/CMakeLists.txt
@@ -6,4 +6,8 @@ FetchContent_Declare(
     GIT_TAG        bc889afb4c5bf1c0d8ee29ef35eaaf4c8bef8a5d
 )
 set(JSON_BuildTests OFF CACHE INTERNAL "")
-FetchContent_MakeAvailable(nlohmann_json)
+FetchContent_GetProperties(nlohmann_json)
+if(NOT nlohmann_json_POPULATED)
+    FetchContent_Populate(nlohmann_json)
+    add_subdirectory(${nlohmann_json_SOURCE_DIR} ${nlohmann_json_BINARY_DIR} EXCLUDE_FROM_ALL)
+endif()