diff --git a/build/scripts/build_cross_tools b/build/scripts/build_cross_tools
index 218a825509..cc7c63d3c4 100755
--- a/build/scripts/build_cross_tools
+++ b/build/scripts/build_cross_tools
@@ -97,7 +97,7 @@ cd $binutilsObjDir
 CFLAGS="-O2" CXXFLAGS="-O2" $buildToolsDir/binutils/configure \
 	--prefix=$installDir --target=i586-pc-haiku --disable-nls \
 	--enable-shared=yes --disable-werror || exit 1
-make $additionalMakeArgs || exit 1
+make -j1 $additionalMakeArgs || exit 1
 make $additionalMakeArgs install || exit 1
 
 PATH=$PATH:$installDir/bin
@@ -157,7 +157,7 @@ eval "sed $sedExpr Makefile.bak > Makefile" || exit 1
 rm Makefile.bak
 
 # make gcc
-make cross || {
+make -j1 cross || {
 	echo "ERROR: Building gcc failed." >&2
 	exit 1
 }