diff --git a/tests/Makefile.am b/tests/Makefile.am
index 6bcbaaeb7d..96019defcb 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -1,11 +1,21 @@
+#
+# Copyright 2020-2022 the Pacemaker project contributors
+#
+# The version control history for this file may have further details.
+#
+# This source code is licensed under the GNU General Public License version 2
+# or later (GPLv2+) WITHOUT ANY WARRANTY.
+#
+
 # tap-test is copied from /usr/share/automake-*/tap-driver.sh.
 EXTRA_DIST = tap-driver.sh \
 	     tap-test \
 	     test-headers.sh
 
 check: check-headers
 
 .PHONY: check-headers
 check-headers:
-	cd $(abs_srcdir); \
-	CFLAGS="$(CFLAGS)" CXXFLAGS="$(CXXFLAGS)" CC="$(CC)" CXX="$(CXX)" CPPFLAGS="$(CPPFLAGS)" LIBS="$(LIBS)" sh test-headers.sh
+	CFLAGS="$(CFLAGS)" CXXFLAGS="$(CXXFLAGS)" CC="$(CC)"		\
+		CXX="$(CXX)" CPPFLAGS="$(CPPFLAGS)" LIBS="$(LIBS)"	\
+		SRCDIR="$(top_srcdir)" sh "$(srcdir)/test-headers.sh"
diff --git a/tests/test-headers.sh b/tests/test-headers.sh
index 0cdda170de..b1204342bc 100644
--- a/tests/test-headers.sh
+++ b/tests/test-headers.sh
@@ -1,44 +1,47 @@
 #!/bin/sh
 #
 # Check public headers for c++ compatibility and consistent protection #ifdefs
 #
 #
 
-INCLUDE_FILES="`find ../include/ -name \*.h -a \! -name \*internal.h`"
+: ${SRCDIR:-..}
+
+INCLUDE_FILES="$(find "${SRCDIR}/include/" -name \*.h \
+                      -a \! -name \*internal.h        \
+                      -a \! -name config.h            \
+                      -a \! -name gettext.h)"
+
+TESTFILE="$(mktemp "${TMPDIR:-/tmp}/test-headers-XXXXXXXXXX.c")"
 
 for i in $INCLUDE_FILES
 do
-    NAME="`echo $i | cut -c12-`"
-
-    # config.h is generated by autoconf
-    # gettext.h is supplied by gettext
-    if [ "$NAME" = "config.h" ] || [ "$NAME" = "gettext.h" ]
-    then
-        continue
-    fi
-    PROTECT="PCMK__`echo $NAME | tr '[:lower:]' '[:upper:]' | tr '/\.' '_' |tr '-' '_' `"
-    PROTECT=`echo $PROTECT|sed 's/_H/__H/'`  # PCMK uses double underscore for .h (eg NAME__H)
+    NAME="$(echo $i | sed -e 's#^.*/include/##')"
+    PROTECT="PCMK__$(echo "$NAME" | tr '[:lower:]/\-\.' '[:upper:]___' | sed 's/_H$/__H/')"
 
-    echo "#include <$NAME>" > _test_file.c
-    echo "#ifndef $PROTECT" >> _test_file.c
-    echo "#error no header protector in file $i" >> _test_file.c
-    echo "#endif" >> _test_file.c
-    echo "int main(void) {return 0;}" >> _test_file.c
+    cat >"$TESTFILE" <<EOF
+#include <$NAME>
+#ifndef $PROTECT
+#error no header protector in file $i
+#endif
+int main(void) {return 0;}
+EOF
 
     # Not including ${CFLAGS} because it seems to break header detection. But we're not really building here
-    ${CC} -I ../include -DHAVE_CONFIG_H ${CPPFLAGS} ${LIBS} _test_file.c -o /dev/null
+    ${CC} -I "${SRCDIR}/include" -DHAVE_CONFIG_H ${CPPFLAGS} ${LIBS} "$TESTFILE" -o /dev/null
     if [ $? -ne 0 ]
     then
+        rm -f "$TESTFILE"
         exit 1
     fi
     if [ "$CXX" ] && [ command -v "$CXX" >/dev/null 2>&1 ]
     then
-        ${CXX} ${CXXFLAGS} ${CPPFLAGS} ${LIBS} -I ../include _test_file.c -o /dev/null
+        ${CXX} ${CXXFLAGS} ${CPPFLAGS} ${LIBS} -I "${SRCDIR}/include" "$TESTFILE" -o /dev/null
         if [ $? -ne 0 ]
         then
+            rm -f "$TESTFILE"
             exit 1
         fi
         echo -n
     fi
-    rm -f _test_file.c
+    rm -f "$TESTFILE"
 done