diff --git a/tests/init.test.sh b/tests/init.test.sh
index 466c68747..eed9be51e 100644
--- a/tests/init.test.sh
+++ b/tests/init.test.sh
@@ -29,7 +29,7 @@ run_sbcl <<EOF
         sb-impl::*sysinit-pathname-function* 'custom-sysinit-pathname)
   (save-lisp-and-die "$tmpcore")
 EOF
-if [ $? != 0 ]; then
+if [ $? -ne 0 ]; then
     echo "failure saving core"
     exit 1
 fi
diff --git a/tests/save6.test.sh b/tests/save6.test.sh
index 7ac815341..cc497a976 100644
--- a/tests/save6.test.sh
+++ b/tests/save6.test.sh
@@ -25,7 +25,7 @@ chmod u+x "$tmpcore"
 EOF
 status=$?
 rm "$tmpcore"
-if [ $status != 42 ]; then
+if [ $status -ne 42 ]; then
     echo "saving runtime options from executable failed"
     exit 1
 fi
diff --git a/tests/save7.test.sh b/tests/save7.test.sh
index fa546e7a2..1e2afe586 100644
--- a/tests/save7.test.sh
+++ b/tests/save7.test.sh
@@ -43,7 +43,7 @@ chmod u+x "${tmpcore}2"
 EOF
 status=$?
 rm "$tmpcore" "${tmpcore}2"
-if [ $status != 42 ]; then
+if [ $status -ne 42 ]; then
     echo "re-saved executable used wrong memory size options"
     exit 1
 fi
diff --git a/tools-for-build/grovel-features.sh b/tools-for-build/grovel-features.sh
index dcf9c4b79..baf677803 100644
--- a/tools-for-build/grovel-features.sh
+++ b/tools-for-build/grovel-features.sh
@@ -10,7 +10,7 @@ featurep() {
     bin="$1-test"
     rm -f $bin
     $GNUMAKE $bin -I ../src/runtime > /dev/null 2>&1 && echo "input" | ./$bin> /dev/null 2>&1
-    if [ "$?" = 104 ]
+    if [ "$?" -eq 104 ]
     then
         printf " :$1"
     fi