+/* These copies need to be numerical or ext/B/Makefile.PL won't think they are
+ * constants */
+#define PMf_MULTILINE (1U<<0)
+#define PMf_SINGLELINE (1U<<1)
+#define PMf_FOLD (1U<<2)
+#define PMf_EXTENDED (1U<<3)
+#define PMf_EXTENDED_MORE (1U<<4)
+#define PMf_NOCAPTURE (1U<<5)
+#define PMf_KEEPCOPY (1U<<6)
+#define PMf_CHARSET (7U<<7)
+#define PMf_STRICT (1U<<10)
+#define PMf_SPLIT (1U<<11)
+
+#if PMf_MULTILINE != RXf_PMf_MULTILINE || PMf_SINGLELINE != RXf_PMf_SINGLELINE || PMf_FOLD != RXf_PMf_FOLD || PMf_EXTENDED != RXf_PMf_EXTENDED || PMf_EXTENDED_MORE != RXf_PMf_EXTENDED_MORE || PMf_KEEPCOPY != RXf_PMf_KEEPCOPY || PMf_SPLIT != RXf_PMf_SPLIT || PMf_CHARSET != RXf_PMf_CHARSET || PMf_NOCAPTURE != RXf_PMf_NOCAPTURE || PMf_STRICT != RXf_PMf_STRICT