feature check

Author: scivision

.github/workflows/ci.yml

@@ -90,7 +90,7 @@ jobs:
     - name: install compilers
       run: |
         apt update -y
-        apt install -y --no-install-recommends ca-certificates gpg curl ninja-build ${{ env.CC }} ${{ env.CXX }} ${{ env.FC }}
+        apt install -y --no-install-recommends ca-certificates gpg curl make ninja-build ${{ env.CC }} ${{ env.CXX }} ${{ env.FC }}
 
     - name: install CMake
       run: |

test/iterator/CMakeLists.txt

@@ -1,3 +1,10 @@
+include(CheckCXXSymbolExists)
+
+check_cxx_symbol_exists(__cpp_lib_to_address "memory" cpp20_to_address)
+if(NOT cpp20_to_address)
+  return()
+endif()
+
 add_library(int_iterator OBJECT lib.cpp)
 target_include_directories(int_iterator PUBLIC ${CMAKE_CURRENT_SOURCE_DIR})