maint: update syntax-check rule to also catch test's -o operator

* cfg.mk (sc_prohibit_test_minus_a): Rename...
(sc_prohibit_test_minus_ao): ...and flag '-o', too.

diff --git a/cfg.mk b/cfg.mk
index bf5eae3093207e6d39fde56ee78d53a124395edc..7fdb069eb877c05e0d5b9e03c4322226416bb909 100644 (file)
--- a/cfg.mk
+++ b/cfg.mk
@@ -270,10 +270,12 @@ sc_preprocessor_indentation:
          echo '$(ME): skipping test $@: cppi not installed' 1>&2;      \
        fi
 
-# Using test's -a operator is not portable.
-sc_prohibit_test_minus_a:
-       @re='\<test .+ -[a] '                                           \
-       msg='use "test C1 && test C2, not "test C1 -''a C2"'            \
+_m1 = use "test C1 && test C2", not "test C1 -''a C2"
+_m2 = use "test C1 || test C2", not "test C1 -''o C2"
+# Using test's -a and -o operators is not portable.
+sc_prohibit_test_minus_ao:
+       @re='\<test .+ -[ao] '                                          \
+       msg='$(_m1); $(_m2)'                                            \
          $(_prohibit_regexp)
 
 sc_copyright_format: