diff --git a/tests/Makefile b/tests/Makefile
index 043108d1..a3062565 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -21,8 +21,8 @@
 # SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 CC=cc -std=c99
-WCFLAGS_GCC=-Wall -W -pedantic -Wshadow -Wpointer-arith -Wcast-qual -Wstrict-prototypes -Wmissing-prototypes -Wswitch-default -Wswitch-enum -Wcast-align -Wpointer-arith -Wbad-function-cast -Wstrict-overflow=5 -Winline -Wundef -Wnested-externs -Wcast-qual -Wshadow -Wunreachable-code -Wlogical-op -Wstrict-aliasing=2 -Wredundant-decls -Wold-style-definition -Wunused-function -ftrapv -Wsign-conversion -Wdate-time -Wconversion -Wformat=2 -Winit-self -Wjump-misses-init -Wstack-protector -Wtrampolines -Wwrite-strings -Wformat-security -Wno-float-conversion
-WCFLAGS_CLANG=-Wall -W -pedantic -Wshadow -Wpointer-arith -Wcast-qual -Wstrict-prototypes -Wmissing-prototypes -Wswitch-default -Wswitch-enum -Wcast-align -Wpointer-arith -Wbad-function-cast -Wstrict-overflow=5 -Winline -Wundef -Wnested-externs -Wcast-qual -Wshadow -Wunreachable-code -Wstrict-aliasing=2 -Wredundant-decls -Wold-style-definition -Wunused-function -ftrapv -Wsign-conversion
+WCFLAGS_GCC=-Wall -W -pedantic -Wshadow -Wpointer-arith -Wcast-qual -Wstrict-prototypes -Wmissing-prototypes -Wswitch-default -Wswitch-enum -Wcast-align -Wpointer-arith -Wbad-function-cast -Wstrict-overflow=5 -Wundef -Wnested-externs -Wcast-qual -Wshadow -Wunreachable-code -Wlogical-op -Wstrict-aliasing=2 -Wredundant-decls -Wold-style-definition -Wunused-function -ftrapv -Wsign-conversion -Wdate-time -Wconversion -Wformat=2 -Winit-self -Wjump-misses-init -Wstack-protector -Wtrampolines -Wwrite-strings -Wformat-security -Wno-float-conversion -O
+WCFLAGS_CLANG=-Wall -W -pedantic -Wshadow -Wpointer-arith -Wcast-qual -Wstrict-prototypes -Wmissing-prototypes -Wswitch-default -Wswitch-enum -Wcast-align -Wpointer-arith -Wbad-function-cast -Wstrict-overflow=5 -Winline -Wundef -Wnested-externs -Wcast-qual -Wshadow -Wunreachable-code -Wstrict-aliasing=2 -Wredundant-decls -Wold-style-definition -Wunused-function -ftrapv -Wsign-conversion -O
 WCFLAGS_CPP=-Wall -W -pedantic -Wshadow -Wpointer-arith -Wcast-qual -Wswitch-default -Wswitch-enum -Wcast-align -Wpointer-arith -Wstrict-overflow=5 -Winline -Wundef -Wcast-qual -Wshadow -Wunreachable-code -Wstrict-aliasing=2 -Wredundant-decls -Wunused-function -ftrapv -Wsign-conversion
 XCFLAGS=
 CFLAGS=$(WCFLAGS_GCC) $(XCFLAGS)