diff --git a/ChangeLog b/ChangeLog
index e3d0ce7f4d5..817ac56ee44 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2009-09-22  Ralf Wildenhues  <Ralf.Wildenhues@gmx.de>
+
+	PR bootstrap/32272
+	* configure.ac: Error out if $srcdir isn't '.' but contains
+	host-${host_noncanonical}.
+	* configure: Regenerate.
+
 2009-09-21  Ralf Wildenhues  <Ralf.Wildenhues@gmx.de>
 
 	* configure.ac: If bootstrapping a combined tree with
diff --git a/configure b/configure
index 720fa239c05..667b514b72c 100755
--- a/configure
+++ b/configure
@@ -2743,6 +2743,11 @@ fi
 # No prefix.
 target_subdir=${target_noncanonical}
 
+# Be sure to cover against remnants of an in-tree build.
+if test $srcdir != .  && test -d $srcdir/host-${host_noncanonical}; then
+  as_fn_error "building out of tree but $srcdir contains host-${host_noncanonical}.
+Use a pristine source tree when building in a separate tree" "$LINENO" 5
+fi
 
 # Skipdirs are removed silently.
 skipdirs=
diff --git a/configure.ac b/configure.ac
index 794a4191d56..e7d44db83dc 100644
--- a/configure.ac
+++ b/configure.ac
@@ -235,6 +235,11 @@ fi
 
 # Find the build and target subdir names.
 GCC_TOPLEV_SUBDIRS
+# Be sure to cover against remnants of an in-tree build.
+if test $srcdir != .  && test -d $srcdir/host-${host_noncanonical}; then
+  AC_MSG_ERROR([building out of tree but $srcdir contains host-${host_noncanonical}.
+Use a pristine source tree when building in a separate tree])
+fi
 
 # Skipdirs are removed silently.
 skipdirs=