diff --git a/diff-sha.sh b/diff-sha.sh
index 5e064a68ef1..74b28b99f66 100644
--- a/diff-sha.sh
+++ b/diff-sha.sh
@@ -230,7 +230,7 @@ else
     PREVIOUS_SHA=$(git rev-parse origin/"$TARGET_BRANCH") && exit_status=$? || exit_status=$?
     DIFF=".."
 
-    if ! git diff --name-only --ignore-submodules=all "$PREVIOUS_SHA$DIFF$CURRENT_SHA" 1>/dev/null 2>&1; then
+    if ! git diff --name-only --ignore-submodules=all "$CURRENT_SHA$DIFF$PREVIOUS_SHA" 1>/dev/null 2>&1; then
       echo "::error::Unable find a diff between $PREVIOUS_SHA and $CURRENT_SHA"
       exit 1
     fi
diff --git a/get-changed-paths.sh b/get-changed-paths.sh
index bff1402becc..e3c87f0008f 100755
--- a/get-changed-paths.sh
+++ b/get-changed-paths.sh
@@ -46,27 +46,27 @@ function get_dirname_max_depth() {
 }
 
 function get_diff() {
-  local base="$1"
-  local sha="$2"
+  local base_sha="$1"
+  local head_sha="$2"
   local filter="$3"
 
   while IFS='' read -r sub; do
-    sub_commit_pre="$(git diff "$base$DIFF$sha" -- "$sub" | { grep '^[-]Subproject commit' || true; } | awk '{print $3}')" && exit_status=$? || exit_status=$?
+    sub_commit_pre="$(git diff "$head_sha$DIFF$base_sha" -- "$sub" | { grep '^[-]Subproject commit' || true; } | awk '{print $3}')" && exit_status=$? || exit_status=$?
     if [[ $exit_status -ne 0 ]]; then
-      echo "::error::Failed to get previous commit for submodule ($sub) between: $base$DIFF$sha"
+      echo "::error::Failed to get previous commit for submodule ($sub) between: $head_sha$DIFF$base_sha"
       exit 1
     fi
 
-    sub_commit_cur="$(git diff "$base$DIFF$sha" -- "$sub" | { grep '^[+]Subproject commit' || true; } | awk '{print $3}')" && exit_status=$? || exit_status=$?
+    sub_commit_cur="$(git diff "$head_sha$DIFF$base_sha" -- "$sub" | { grep '^[+]Subproject commit' || true; } | awk '{print $3}')" && exit_status=$? || exit_status=$?
     if [[ $exit_status -ne 0 ]]; then
-      echo "::error::Failed to get current commit for submodule ($sub) between: $base$DIFF$sha"
+      echo "::error::Failed to get current commit for submodule ($sub) between: $head_sha$DIFF$base_sha"
       exit 1
     fi
 
     if [ -n "$sub_commit_cur" ]; then
       (
         cd "$sub" && (
-          # the strange magic number is a hardcoded "empty tree" commit sha
+          # the strange magic number is a hardcoded "empty tree" commit base_sha
           get_diff "${sub_commit_pre:-4b825dc642cb6eb9a060e54bf8d69288fbee4904}" "${sub_commit_cur}" "$filter" | awk -v r="$sub" '{ print "" r "/" $0}'
         )
       )
@@ -74,36 +74,36 @@ function get_diff() {
   done < <(git submodule | awk '{print $2}')
 
   if [[ "$INPUT_DIR_NAMES" == "true" ]]; then
-    git diff --diff-filter="$filter" --name-only --ignore-submodules=all --no-merges "$base$DIFF$sha" | xargs -I {} dirname {} | get_dirname_max_depth | uniq && exit_status=$? || exit_status=$?
+    git diff --diff-filter="$filter" --name-only --ignore-submodules=all "$head_sha$DIFF$base_sha" | xargs -I {} dirname {} | get_dirname_max_depth | uniq && exit_status=$? || exit_status=$?
 
     if [[ $exit_status -ne 0 ]]; then
-      echo "::error::Failed to get changed directories between: $base$DIFF$sha"
+      echo "::error::Failed to get changed directories between: $head_sha$DIFF$base_sha"
       exit 1
     fi
   else
-    git diff --diff-filter="$filter" --name-only --ignore-submodules=all --no-merges "$base$DIFF$sha" && exit_status=$? || exit_status=$?
+    git diff --diff-filter="$filter" --name-only --ignore-submodules=all "$head_sha$DIFF$base_sha" && exit_status=$? || exit_status=$?
 
     if [[ $exit_status -ne 0 ]]; then
-      echo "::error::Failed to get changed files between: $base$DIFF$sha"
+      echo "::error::Failed to get changed files between: $head_sha$DIFF$base_sha"
       exit 1
     fi
   fi
 }
 
 function get_renames() {
-  local base="$1"
-  local sha="$2"
+  local base_sha="$1"
+  local head_sha="$2"
 
   while IFS='' read -r sub; do
-    sub_commit_pre="$(git diff "$base$DIFF$sha" -- "$sub" | { grep '^[-]Subproject commit' || true; } | awk '{print $3}')" && exit_status=$? || exit_status=$?
+    sub_commit_pre="$(git diff "$head_sha$DIFF$base_sha" -- "$sub" | { grep '^[-]Subproject commit' || true; } | awk '{print $3}')" && exit_status=$? || exit_status=$?
     if [[ $exit_status -ne 0 ]]; then
-      echo "::error::Failed to get previous commit for submodule ($sub) between: $base$DIFF$sha"
+      echo "::error::Failed to get previous commit for submodule ($sub) between: $head_sha$DIFF$base_sha"
       exit 1
     fi
 
-    sub_commit_cur="$(git diff "$base$DIFF$sha" -- "$sub" | { grep '^[+]Subproject commit' || true; } | awk '{print $3}')" && exit_status=$? || exit_status=$?
+    sub_commit_cur="$(git diff "$head_sha$DIFF$base_sha" -- "$sub" | { grep '^[+]Subproject commit' || true; } | awk '{print $3}')" && exit_status=$? || exit_status=$?
     if [[ $exit_status -ne 0 ]]; then
-      echo "::error::Failed to get current commit for submodule ($sub) between: $base$DIFF$sha"
+      echo "::error::Failed to get current commit for submodule ($sub) between: $head_sha$DIFF$base_sha"
       exit 1
     fi
 
@@ -118,17 +118,17 @@ function get_renames() {
   done < <(git submodule | awk '{print $2}')
 
   if [[ "$INPUT_DIR_NAMES" == "true" ]]; then
-    git log --name-status --ignore-submodules=all "$base" "$sha" | { grep -E "^R" || true; } | awk -F '\t' -v d="$INPUT_OLD_NEW_SEPARATOR" '{print $2d$3}' | xargs -I {} dirname {} | get_dirname_max_depth | uniq && exit_status=$? || exit_status=$?
+    git log --name-status --ignore-submodules=all "$head_sha" "$base_sha" | { grep -E "^R" || true; } | awk -F '\t' -v d="$INPUT_OLD_NEW_SEPARATOR" '{print $2d$3}' | xargs -I {} dirname {} | get_dirname_max_depth | uniq && exit_status=$? || exit_status=$?
 
     if [[ $exit_status -ne 0 ]]; then
-      echo "::error::Failed to get renamed directories between: $base → $sha"
+      echo "::error::Failed to get renamed directories between: $head_sha → $base_sha"
       exit 1
     fi
   else
-    git log --name-status --ignore-submodules=all "$base" "$sha" | { grep -E "^R" || true; } | awk -F '\t' -v d="$INPUT_OLD_NEW_SEPARATOR" '{print $2d$3}' && exit_status=$? || exit_status=$?
+    git log --name-status --ignore-submodules=all "$head_sha" "$base_sha" | { grep -E "^R" || true; } | awk -F '\t' -v d="$INPUT_OLD_NEW_SEPARATOR" '{print $2d$3}' && exit_status=$? || exit_status=$?
 
     if [[ $exit_status -ne 0 ]]; then
-      echo "::error::Failed to get renamed files between: $base → $sha"
+      echo "::error::Failed to get renamed files between: $head_sha → $base_sha"
       exit 1
     fi
   fi