diff --git a/ament_cmake_auto/CMakeLists.txt b/ament_cmake_auto/CMakeLists.txt
index a8d2919b..fb35123e 100644
--- a/ament_cmake_auto/CMakeLists.txt
+++ b/ament_cmake_auto/CMakeLists.txt
@@ -1,4 +1,4 @@
-cmake_minimum_required(VERSION 2.8.3)
+cmake_minimum_required(VERSION 3.5)
 
 project(ament_cmake_auto NONE)
 
diff --git a/ament_cmake_auto/cmake/ament_auto_add_executable.cmake b/ament_cmake_auto/cmake/ament_auto_add_executable.cmake
index 02e6742c..ba0b6763 100644
--- a/ament_cmake_auto/cmake/ament_auto_add_executable.cmake
+++ b/ament_cmake_auto/cmake/ament_auto_add_executable.cmake
@@ -74,7 +74,7 @@ macro(ament_auto_add_executable target)
       "${CMAKE_CURRENT_SOURCE_DIR}/include")
   endif()
   # link against other libraries of this package
-  if(NOT "${${PROJECT_NAME}_LIBRARIES} " STREQUAL " " AND
+  if(NOT ${PROJECT_NAME}_LIBRARIES STREQUAL "" AND
       NOT ARG_NO_TARGET_LINK_LIBRARIES)
     target_link_libraries("${target}" ${${PROJECT_NAME}_LIBRARIES})
   endif()
diff --git a/ament_cmake_auto/cmake/ament_auto_add_library.cmake b/ament_cmake_auto/cmake/ament_auto_add_library.cmake
index 9ddb717c..ce2e063d 100644
--- a/ament_cmake_auto/cmake/ament_auto_add_library.cmake
+++ b/ament_cmake_auto/cmake/ament_auto_add_library.cmake
@@ -74,7 +74,7 @@ macro(ament_auto_add_library target)
       "${CMAKE_CURRENT_SOURCE_DIR}/include")
   endif()
   # link against other libraries of this package
-  if(NOT "${${PROJECT_NAME}_LIBRARIES} " STREQUAL " " AND
+  if(NOT ${PROJECT_NAME}_LIBRARIES STREQUAL "" AND
       NOT ARG_NO_TARGET_LINK_LIBRARIES)
     target_link_libraries("${target}" ${${PROJECT_NAME}_LIBRARIES})
   endif()
diff --git a/ament_cmake_auto/cmake/ament_auto_package.cmake b/ament_cmake_auto/cmake/ament_auto_package.cmake
index 43ac1d67..c5d040e1 100644
--- a/ament_cmake_auto/cmake/ament_auto_package.cmake
+++ b/ament_cmake_auto/cmake/ament_auto_package.cmake
@@ -50,7 +50,7 @@ macro(ament_auto_package)
   endif()
 
   # export and install all libraries
-  if(NOT "${${PROJECT_NAME}_LIBRARIES} " STREQUAL " ")
+  if(NOT ${PROJECT_NAME}_LIBRARIES STREQUAL "")
     ament_export_libraries(${${PROJECT_NAME}_LIBRARIES})
     install(
       TARGETS ${${PROJECT_NAME}_LIBRARIES}
@@ -61,7 +61,7 @@ macro(ament_auto_package)
   endif()
 
   # install all executables
-  if(NOT "${${PROJECT_NAME}_EXECUTABLES} " STREQUAL " ")
+  if(NOT ${PROJECT_NAME}_EXECUTABLES STREQUAL "")
     install(
       TARGETS ${${PROJECT_NAME}_EXECUTABLES}
       ARCHIVE DESTINATION lib