diff --git a/src/stub/scripts/check_whitespace.sh b/src/stub/scripts/check_whitespace.sh
index 487b7b1c..91f84269 100755
--- a/src/stub/scripts/check_whitespace.sh
+++ b/src/stub/scripts/check_whitespace.sh
@@ -11,6 +11,7 @@ find . \
     -type d -name '.hg' -prune -o \
     -type d -name 'build*' -prune -o \
     -type d -name 'tmp*' -prune -o \
+    -type d -name 'vendor' -prune -o \
     -type f -iname '*.bat' -prune -o \
     -type f -iname '*.exe' -prune -o \
     -type f -iname '*.o' -prune -o \
diff --git a/src/stub/scripts/check_whitespace_git.sh b/src/stub/scripts/check_whitespace_git.sh
index 2c488c89..92d1eea3 100755
--- a/src/stub/scripts/check_whitespace_git.sh
+++ b/src/stub/scripts/check_whitespace_git.sh
@@ -10,6 +10,7 @@ set -e; set -o pipefail
 git ls-files --full-name -z | perl -0 -n -e '
     s,^,./,;
     if (m,^\./src/lzma-sdk(\0|$),) { }
+    if (m,^\./vendor/,) { }
     elsif (m,\.bat(\0|$),) { }
     elsif (m,\.exe(\0|$),) { }
     else { print; }
diff --git a/src/stub/src/c/Makevars.lzma b/src/stub/src/c/Makevars.lzma
index 6537658c..cb4e336c 100644
--- a/src/stub/src/c/Makevars.lzma
+++ b/src/stub/src/c/Makevars.lzma
@@ -1,14 +1,14 @@
-# UPX unconditionally uses its own version in src/lzma-sdk because
+# UPX unconditionally uses its own version in vendor/lzma-sdk because
 # that version works fine since 2006 and that is the only version
 # that is actually sufficiently tested!!!
 
-override UPX_LZMADIR := $(top_srcdir)/src/lzma-sdk
+override UPX_LZMADIR := $(top_srcdir)/vendor/lzma-sdk
 override UPX_LZMA_VERSION := 0x443
 
 ifeq ($(wildcard $(UPX_LZMADIR)/C/7zip/.),)
   ifneq ($(wildcard $(top_srcdir)/.git/.),)
     $(error ERROR: missing git submodule; run 'git submodule update --init --recursive')
   else
-    $(error ERROR: missing directory src/lzma-sdk/; visit https://github.com/upx/upx-lzma-sdk )
+    $(error ERROR: missing directory vendor/lzma-sdk/; visit https://github.com/upx/upx-vendor-lzma-sdk )
   endif
 endif