diff --git a/client/Makefile b/client/Makefile
index 1f857e584..1cdc18f73 100644
--- a/client/Makefile
+++ b/client/Makefile
@@ -56,8 +56,13 @@ ZLIB = $(OBJDIR)/libz.a
 LIBS = -I$(LUALIBPATH) -I$(MBEDTLSLIBPATH) -I$(JANSSONLIBPATH) -I$(CBORLIBPATH) -I$(ZLIBPATH) -I$(REVENGPATH) -I$(AMIIBOLIBPATH) -I$(HARDNESTEDPATH) -I$(CLIPARSERPATH)
 INCLUDES_CLIENT += -I./src -I../include -I../common -I../common_fpga $(LIBS)
 #CFLAGS ?= -Wall -Werror -O3
-CFLAGS ?= -Wall -Werror -O3 -Wchar-subscripts -Wundef -Wcast-align -Wwrite-strings -Wunused -Wuninitialized -Wpointer-arith -Winline -Wformat -Wformat-security -Winit-self -Wmissing-include-dirs -Wstrict-prototypes -Wnested-externs -Wmissing-declarations
-#  -Wshadow -Wmissing-prototypes -Wredundant-decls
+ifneq ($(platform),Darwin)
+# readline has strict-prototype issues
+CFLAGS ?= -Wall -Werror -O3 -Wmissing-prototypes -Wchar-subscripts -Wundef -Wcast-align -Wwrite-strings -Wunused -Wuninitialized -Wpointer-arith -Winline -Wformat -Wformat-security -Winit-self -Wmissing-include-dirs -Wnested-externs -Wmissing-declarations
+else
+CFLAGS ?= -Wall -Werror -O3 -Wmissing-prototypes -Wchar-subscripts -Wundef -Wcast-align -Wwrite-strings -Wunused -Wuninitialized -Wpointer-arith -Winline -Wformat -Wformat-security -Winit-self -Wmissing-include-dirs -Wstrict-prototypes -Wnested-externs -Wmissing-declarations
+endif
+#  -Wshadow -Wredundant-decls
 #  -Wbad-function-cast -Wextra -Wswitch-enum -Wold-style-definition
 
 # We cannot just use CFLAGS+=... because it has impact on sub-makes if CFLAGS is defined in env: