diff --git a/tests/Makefile b/tests/Makefile
index c09bf680..89630c06 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -22,7 +22,7 @@
 
 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 -Wstrict-prototypes -Winline -Wundef -Wnested-externs -Wcast-qual -Wshadow -Wunreachable-code -Wlogical-op -Wstrict-aliasing=2 -Wredundant-decls -Wold-style-definition -Wno-unused-function -ftrapv
-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 -Wstrict-prototypes -Winline -Wundef -Wnested-externs -Wcast-qual -Wshadow -Wunreachable-code -Wstrict-aliasing=2 -Wredundant-decls -Wold-style-definition -Wno-unused-function -ftrapv
+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 -Wstrict-prototypes -Winline -Wundef -Wnested-externs -Wcast-qual -Wshadow -Wunreachable-code -Wstrict-aliasing=2 -Wredundant-decls -Wold-style-definition -Wno-unused-function -ftrapv -Wsign-conversion
 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 -Wno-unused-function -ftrapv
 XCFLAGS=
 CFLAGS=$(WCFLAGS_GCC) $(XCFLAGS)