Check macros for headers

.github/workflows/check_misc.yml

@@ -9,3 +9,9 @@ jobs:
       - name: Check if C-sources are US-ASCII
         run: |
           ! grep -r -n '[^	 -~]' *.[chy] include internal win32/*.[ch]
+      - name: Check for header macros
+        run: |
+          ! for header in ruby/*.h; do \
+            git grep -l -F -e $header -e HAVE_`echo $header | tr a-z./ A-Z__` -- . > /dev/null || echo $header
+          done | grep -F .
+        working-directory: include