diff --git a/Makefile b/Makefile
index 0eaffc23d2..7baff23a57 100644
--- a/Makefile
+++ b/Makefile
@@ -310,7 +310,7 @@ ifneq ($(V),1)
    Q := @
 endif
 
-OPTIMIZE_FLAG = -O3
+OPTIMIZE_FLAG = -O3 -ffast-math
 ifeq ($(DEBUG), 1)
    OPTIMIZE_FLAG = -O0
 endif
diff --git a/Makefile.win b/Makefile.win
index ff02d01eea..79396f99bc 100644
--- a/Makefile.win
+++ b/Makefile.win
@@ -221,8 +221,8 @@ ifeq ($(DEBUG), 1)
    CFLAGS += -O0 -g
    CXXFLAGS += -O0 -g
 else
-   CFLAGS += -O3
-   CXXFLAGS += -O3
+   CFLAGS += -O3 -ffast-math
+   CXXFLAGS += -O3 -ffast-math
    LDCXXFLAGS += -s
 endif
 
diff --git a/audio/test/Makefile b/audio/test/Makefile
index 26089ba76c..10f700ba15 100644
--- a/audio/test/Makefile
+++ b/audio/test/Makefile
@@ -11,7 +11,7 @@ TESTS := test-hermite \
 	test-sinc-highest \
 	test-snr-sinc-highest
 
-CFLAGS += -O3 -g -Wall -pedantic -march=native -std=gnu99 -DRESAMPLER_TEST
+CFLAGS += -O3 -ffast-math -g -Wall -pedantic -march=native -std=gnu99 -DRESAMPLER_TEST
 LDFLAGS += -lm
 
 all: $(TESTS)