diff --git a/Tests/FindBLAS/Test/CMakeLists.txt b/Tests/FindBLAS/Test/CMakeLists.txt
index 3183776f22..6d9461b35e 100644
--- a/Tests/FindBLAS/Test/CMakeLists.txt
+++ b/Tests/FindBLAS/Test/CMakeLists.txt
@@ -4,6 +4,9 @@ include(CTest)
 
 find_package(BLAS REQUIRED)
 
+# Configure the test case to match BLAS's integer type ABI.
+# FindBLAS defaults to 32-bit integers if BLA_SIZEOF_INTEGER
+# is not already set in the cache.
 if(NOT BLA_SIZEOF_INTEGER)
   set(BLA_SIZEOF_INTEGER 4)
 endif()
diff --git a/Tests/FindLAPACK/Test/CMakeLists.txt b/Tests/FindLAPACK/Test/CMakeLists.txt
index 55cd1ee073..439d02654b 100644
--- a/Tests/FindLAPACK/Test/CMakeLists.txt
+++ b/Tests/FindLAPACK/Test/CMakeLists.txt
@@ -4,6 +4,9 @@ include(CTest)
 
 find_package(LAPACK REQUIRED)
 
+# Configure the test case to match LAPACK's integer type ABI.
+# FindLAPACK defaults to 32-bit integers if BLA_SIZEOF_INTEGER
+# is not already set in the cache.
 if(NOT BLA_SIZEOF_INTEGER)
   set(BLA_SIZEOF_INTEGER 4)
 endif()