diff --git a/gcc/ada/libgnat/system-linux-arm.ads b/gcc/ada/libgnat/system-linux-arm.ads
--- a/gcc/ada/libgnat/system-linux-arm.ads
+++ b/gcc/ada/libgnat/system-linux-arm.ads
@@ -70,7 +70,7 @@ package System is
 
    Storage_Unit : constant := 8;
    Word_Size    : constant := Standard'Word_Size;
-   Memory_Size  : constant := 2 ** Long_Integer'Size;
+   Memory_Size  : constant := 2 ** Word_Size;
 
    --  Address comparison