--- a/Makefile.in
+++ b/Makefile.in
@@ -9,7 +9,7 @@
 install-suid-root: exec_perms = 4755
 
 CC	 ?= @CC@
-CFLAGS	 ?= @CFLAGS@ @LIBNL3_CLI_CFLAGS@
+CFLAGS	 = @CFLAGS@ @LIBNL3_CLI_CFLAGS@
 CPPFLAGS ?= @CPPFLAGS@
 LDFLAGS  ?= @LDFLAGS@
 DEFS	 ?= @DEFS@