diff --git a/Makefile b/Makefile
index e003ae6..ae29f1c 100644
--- a/Makefile
+++ b/Makefile
@@ -27,7 +27,7 @@ DEPS := $(subst .cpp,.d,$(SRCS))
 
 CXX ?= g++
 
-CXXFLAGS := $(CXXFLAGS) -Wshadow -Wall -Wpedantic -Wextra -g -fno-strict-aliasing -std=c++17 -fPIC
+CXXFLAGS += -Wshadow -Wall -Wpedantic -Wextra -g -std=c++17 -fPIC
 ifeq ($(DEBUG),1)
 	CXXFLAGS += -D DEBUG -O0
 else
diff --git a/sciotest/Makefile b/sciotest/Makefile
index d515b81..d9a31e9 100644
--- a/sciotest/Makefile
+++ b/sciotest/Makefile
@@ -15,7 +15,7 @@ MANDIR ?= $(DATADIR)/man
 RM := /bin/rm -f
 INSTALL := /usr/bin/install -c
 
-CXXFLAGS := $(CXXFLAGS) -Wshadow -Wall -Wpedantic -Wextra -g -fno-strict-aliasing -std=c++17 -pthread
+CXXFLAGS += -Wshadow -Wall -Wpedantic -Wextra -g -std=c++17
 ifeq ($(DEBUG),1)
 	CXXFLAGS += -D DEBUG -O0
 else