BUILD: properly report when USE_ZLIB and USE_SLZ are used together
Use #error here otherwise the errors are hard to spot for the casual
user.
diff --git a/include/types/compression.h b/include/types/compression.h
index ecbd5a1..b79d770 100644
--- a/include/types/compression.h
+++ b/include/types/compression.h
@@ -24,6 +24,9 @@
#define _TYPES_COMP_H
#if defined(USE_SLZ)
+#ifdef USE_ZLIB
+#error "Cannot build with both USE_SLZ and USE_ZLIB at the same time."
+#endif
#include <slz.h>
#elif defined(USE_ZLIB)
#include <zlib.h>