diff --git a/t/t1004-read-tree-m-u-wf.sh b/t/t1004-read-tree-m-u-wf.sh
index 3e72aff470..c70cf42300 100755
--- a/t/t1004-read-tree-m-u-wf.sh
+++ b/t/t1004-read-tree-m-u-wf.sh
@@ -30,7 +30,7 @@ test_expect_success 'two-way not clobbering' '
 
 	echo >file2 master creates untracked file2 &&
 	echo >subdir/file2 master creates untracked subdir/file2 &&
-	if err=`read_tree_u_must_succeed -m -u master side 2>&1`
+	if err=$(read_tree_u_must_succeed -m -u master side 2>&1)
 	then
 		echo should have complained
 		false
@@ -43,7 +43,7 @@ echo file2 >.gitignore
 
 test_expect_success 'two-way with incorrect --exclude-per-directory (1)' '
 
-	if err=`read_tree_u_must_succeed -m --exclude-per-directory=.gitignore master side 2>&1`
+	if err=$(read_tree_u_must_succeed -m --exclude-per-directory=.gitignore master side 2>&1)
 	then
 		echo should have complained
 		false
@@ -54,7 +54,7 @@ test_expect_success 'two-way with incorrect --exclude-per-directory (1)' '
 
 test_expect_success 'two-way with incorrect --exclude-per-directory (2)' '
 
-	if err=`read_tree_u_must_succeed -m -u --exclude-per-directory=foo --exclude-per-directory=.gitignore master side 2>&1`
+	if err=$(read_tree_u_must_succeed -m -u --exclude-per-directory=foo --exclude-per-directory=.gitignore master side 2>&1)
 	then
 		echo should have complained
 		false
@@ -95,7 +95,7 @@ test_expect_success 'three-way not clobbering a working tree file' '
 	git checkout master &&
 	echo >file3 file three created in master, untracked &&
 	echo >subdir/file3 file three created in master, untracked &&
-	if err=`read_tree_u_must_succeed -m -u branch-point master side 2>&1`
+	if err=$(read_tree_u_must_succeed -m -u branch-point master side 2>&1)
 	then
 		echo should have complained
 		false