diff --git a/gnu/usr.bin/cc/Makefile.inc b/gnu/usr.bin/cc/Makefile.inc
index 79c573e10a3..62f86bebc6f 100644
--- a/gnu/usr.bin/cc/Makefile.inc
+++ b/gnu/usr.bin/cc/Makefile.inc
@@ -29,6 +29,9 @@ version!=	sed -e 's/.*\"\([^ \"]*\)[ \"].*/\1/' < ${GCCDIR}/version.c
 
 CFLAGS+=	-DFREEBSD_NATIVE -DIN_GCC -DHAVE_CONFIG_H
 CFLAGS+=	-DPREFIX=\"${TOOLS_PREFIX}/usr\"
+
+# If building 64-bit longs for the i386, "_LARGE_LONG" should also be defined
+# to get the proper sizes in limits.h
 .if defined(LONG_TYPE_SIZE)
 CFLAGS+=	-DLONG_TYPE_SIZE=${LONG_TYPE_SIZE}
 .endif