diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7336f19d..f15af2ad 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -25,6 +25,10 @@ if(BUILD_4 AND BUILD_D)
   set(kinds "4" "d")
 elseif(BUILD_4 AND NOT BUILD_D)
   set(kinds "4")
+  if(BUILD_TESTING)
+    set(BUILD_TESTING OFF)
+    message(WARNING "Disabling build testing for BUILD_4-only case")
+  endif()
 elseif(BUILD_D AND NOT BUILD_4)
   set(kinds "d")
 else()
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 6877cbaa..f5d8c33f 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -29,7 +29,6 @@ endif()
 
 # We build a version of the library with 4-byte reals (_4), and one
 # with 8-byte reals (_d).
-set(kinds "4" "d")
 foreach(kind ${kinds})
   set(lib_name ${PROJECT_NAME}_${kind})
   set(module_dir "${CMAKE_CURRENT_BINARY_DIR}/include_${kind}")