diff --git a/extras/buildbot-checker.sh b/extras/buildbot-checker.sh
index 483d40e..6c9a5f7 100755
--- a/extras/buildbot-checker.sh
+++ b/extras/buildbot-checker.sh
@@ -45,10 +45,8 @@ if [ -z "$MAKE" ]; then
 fi
 
 echo "\$MAKE is '$MAKE'"
-
-# Unset $MAKE so submakes don't use it.
-MAKECOMMAND="$MAKE"
-unset MAKE
+MAKECMD="$MAKE"
+unset MAKE  # prevent warnings about jobserver mode.
 
 set -x
 set -e
@@ -74,7 +72,7 @@ PATH="$CHECKERDIR/bin:$PATH" scan-build -o analysis cmake -Wno-dev -DPHYSFS_BUIL
 #CC="$CHECKERDIR/libexec/ccc-analyzer" CFLAGS="-O0 -Wno-deprecated-declarations" LDFLAGS="-Wno-liblto" ../configure --enable-assertions=enabled
 
 rm -rf analysis
-PATH="$CHECKERDIR/bin:$PATH" scan-build -o analysis $MAKECOMMAND
+PATH="$CHECKERDIR/bin:$PATH" scan-build -o analysis $MAKECMD
 
 if [ `ls -A analysis |wc -l` == 0 ] ; then
     mkdir analysis/zarro
diff --git a/extras/buildbot-emscripten.sh b/extras/buildbot-emscripten.sh
index b1d00d6..e96e8ac 100755
--- a/extras/buildbot-emscripten.sh
+++ b/extras/buildbot-emscripten.sh
@@ -43,6 +43,8 @@ if [ -z "$MAKE" ]; then
 fi
 
 echo "\$MAKE is '$MAKE'"
+MAKECMD="$MAKE"
+unset MAKE  # prevent warnings about jobserver mode.
 
 echo "Setting up Emscripten SDK environment..."
 source "$ENVSCRIPT"
@@ -58,7 +60,7 @@ echo "Configuring..."
 emcmake cmake -G "Unix Makefiles" -DPHYSFS_BUILD_SHARED=False -DCMAKE_BUILD_TYPE=MinSizeRel .. || exit $?
 
 echo "Building..."
-emmake $MAKE || exit $?
+emmake $MAKECMD || exit $?
 
 set -e
 rm -rf "$TARBALL" physfs-emscripten
diff --git a/extras/buildbot-raspberrypi.sh b/extras/buildbot-raspberrypi.sh
index 9b7ed7d..61064d6 100755
--- a/extras/buildbot-raspberrypi.sh
+++ b/extras/buildbot-raspberrypi.sh
@@ -28,6 +28,10 @@ if [ "x$MAKE" == "x" ]; then
     MAKE="make -j$NCPU"
 fi
 
+echo "\$MAKE is '$MAKE'"
+MAKECMD="$MAKE"
+unset MAKE  # prevent warnings about jobserver mode.
+
 BUILDBOTDIR="raspberrypi-buildbot"
 PARENTDIR="$PWD"
 
@@ -51,7 +55,7 @@ cmake -G "Unix Makefiles" \
     -DCMAKE_FIND_ROOT_PATH_MODE_INCLUDE=ONLY \
     ..
 
-$MAKE
+$MAKECMD
 
 rm -rf "$TARBALL" physfs-raspberrypi
 mkdir -p physfs-raspberrypi