diff --git a/Makefile b/Makefile
index 31eacd39c..23cc84d0f 100644
--- a/Makefile
+++ b/Makefile
@@ -71,6 +71,10 @@ LDLIBS   =
 CFLAGS  += -std=c11 -MMD -mcx16 -I$(BUILDDIR)/include -I$(SRCDIR)/include
 CFLAGS  += -Wall -Werror -fdiagnostics-color=auto -D_POSIX_C_SOURCE=200809L -D_GNU_SOURCE=1
 
+ifeq ($(PLATFORM),Darwin)
+	CFLAGS += -D_DARWIN_C_SOURCE
+endif
+
 LDFLAGS += -L$(BUILDDIR)
 
 # Some tools
diff --git a/lib/Makefile.inc b/lib/Makefile.inc
index 48f0c1d13..29e513a41 100644
--- a/lib/Makefile.inc
+++ b/lib/Makefile.inc
@@ -26,10 +26,6 @@ LIBS = $(patsubst %, lib%, $(SONAMES))
 
 LIB_CFLAGS  += $(CFLAGS) -fPIC
 
-ifeq ($(shell uname),Darwin)
-	 LIB_CFLAGS += -D_DARWIN_C_SOURCE=1
-endif
-
 include $(patsubst %, lib/Makefile.%.inc, $(SONAMES))
 
 $(BUILDDIR)/include/villas/config.h: include/villas/config.h.in Makefile.config | $$(dir $$@)