Check that there are no library modules that use the old "sp" symbol instead

of "c_sp".

.github/checks/Makefile

@@ -40,4 +40,7 @@ sorted: sorted.sh sorted_codeopt.sh sorted_opcodes.sh
 	@./sorted_codeopt.sh
 	@./sorted_opcodes.sh
 
+checksp: checksp.sh
+	@./checksp.sh
+
 endif

.github/checks/checksp.sh

@@ -0,0 +1,22 @@
+#! /bin/bash
+OD65_EXE=../bin/od65
+CHECK_PATH=../../libwrk
+
+cd "${CHECK_PATH}" || {
+    echo "error: Directory ${CHECK_PATH} doesn't seem to exist" >&2
+    exit 1
+}
+
+[ -x "${OD65_EXE}" ] || {
+    echo "error: This check requires the od65 executable to be built" >&2
+    exit 1
+}
+
+EXITCODE=0
+find . -name \*.o -print | while read OBJ; do
+    "${OD65_EXE}" --dump-imports "${OBJ}" | grep -q "\"sp\"" && {
+        echo "error: Usage of symbol 'sp' found in module ${OBJ}" >&2
+        EXITCODE=1
+    }
+done
+exit ${EXITCODE}

.github/workflows/build-on-pull-request.yml

@@ -39,6 +39,9 @@ jobs:
       - name: Build the platform libraries.
         shell: bash
         run: make -j2 lib QUIET=1
+      - name: check test that no modules use sp
+        shell: bash
+        run: make -j2 checksp QUIET=1             
       - name: Run the regression tests.
         shell: bash
         run: make -j2 test QUIET=1