diff --git a/config/libc/glibc.in.2 b/config/libc/glibc.in.2
index 9d3c2e10..93b7b59b 100644
--- a/config/libc/glibc.in.2
+++ b/config/libc/glibc.in.2
@@ -136,12 +136,15 @@ config LIBC_LOCALES
       which is required in order to support internationalization.
 
 if LIBC_glibc && LIBC_LOCALES
-comment "WARNING!                                                     "
+comment "WARNING!                                                      "
 comment "|  The built locales will be usable if and only if the build  "
 comment "|  machine and the target:                                    "
 comment "|   - have the same endianness,                               "
 comment "|   - and have the same alignment requirements for uint32_t.  "
 comment "|  You will have to check by yourself (for now).              "
+comment "WARNING!                                                      "
+comment "|  Building GLIBC locales requires that GLIBC supports        "
+comment "|  the build machine as the target.                           "
 endif # LIBC_glibc && LIBC_LOCALES
 
 if KERNEL_linux