diff --git a/src/Makevars b/src/Makevars
index dfb73ffc..00ba252d 100644
--- a/src/Makevars
+++ b/src/Makevars
@@ -37,7 +37,7 @@ CONFIGURE_FLAGS="--quiet"
 # PKG_CPPFLAGS += -Wno-deprecated-declarations -Wno-parentheses
 # Fedora 28 defines _GLIBCXX_ASSERTIONS, so we better define it everywhere
 # to catch issues earlier.
-# PKG_CPPFLAGS += -D_GLIBCXX_ASSERTIONS
+PKG_CPPFLAGS += -D_GLIBCXX_ASSERTIONS
 
 
 $(SHLIB): libuv/.libs/libuv.a http-parser/http_parser.o sha1/sha1.o base64/base64.o