diff --git a/BUILDING b/BUILDING
index 50efcc318314..46098c35eff4 100644
--- a/BUILDING
+++ b/BUILDING
@@ -28,7 +28,8 @@ REQUIREMENTS
      host system to create a build toolchain for the target architecture.  The
      host system must have at least C and C++ compilers in order to create the
      toolchain (make is not required); all other tools are created as part of
-     the NetBSD build process.
+     the NetBSD build process.  (See the environment variables section below
+     if you need to override or manually select your compilers.)
 
 FILES
    Source tree layout
@@ -93,6 +94,10 @@ CONFIGURATION
    Environment variables
      Several environment variables control the behaviour of NetBSD builds.
 
+     HOST_CC           Path name to C compiler used to create the toolchain.
+
+     HOST_CXX          Path name to C++ compiler used to create the toolchain.
+
      MACHINE           Machine type.
 
      MACHINE_ARCH      Machine architecture.
diff --git a/doc/BUILDING.mdoc b/doc/BUILDING.mdoc
index b61f2abccf3a..b8162235bcec 100644
--- a/doc/BUILDING.mdoc
+++ b/doc/BUILDING.mdoc
@@ -1,4 +1,4 @@
-.\"	$NetBSD: BUILDING.mdoc,v 1.37 2004/10/12 04:07:09 jmc Exp $
+.\"	$NetBSD: BUILDING.mdoc,v 1.38 2005/02/15 18:41:18 reed Exp $
 .\"
 .\" Copyright (c) 2001-2004 The NetBSD Foundation, Inc.
 .\" All rights reserved.
@@ -94,6 +94,8 @@ compilers in order to create the toolchain
 is not required); all other tools are created as part of the
 .Nx
 build process.
+(See the environment variables section below if you need
+to override or manually select your compilers.)
 .
 .Sh FILES
 .
@@ -187,6 +189,13 @@ builds.
 .
 .Bl -tag -width "MAKEOBJDIRPREFIX"
 .
+.
+.It Sy HOST_CC
+Path name to C compiler used to create the toolchain.
+.
+.It Sy HOST_CXX
+Path name to C++ compiler used to create the toolchain.
+.
 .It Sy MACHINE
 Machine type.
 .