GCC 4.2.1 doesn't recognize the "-Wtype-limits" option.

Also drop -Werror

Index: Makefile
--- Makefile.orig
+++ Makefile
@@ -9,7 +9,7 @@ KODEV=kodev/kodev
 KOREPATH?=$(shell pwd)
 KORE_CRYPTO?=crypto
 INSTALL_DIR=$(PREFIX)/bin
-MAN_DIR?=$(PREFIX)/share/man
+MAN_DIR?=$(PREFIX)/man
 SHARE_DIR=$(PREFIX)/share/kore
 INCLUDE_DIR=$(PREFIX)/include/kore
 TLS_BACKEND?=openssl
@@ -31,10 +31,10 @@ S_SRC+= src/tls_$(TLS_BACKEND).c
 FEATURES=
 FEATURES_INC=
 
-CFLAGS+=-Wall -Werror -Wstrict-prototypes -Wmissing-prototypes
+CFLAGS+=-Wall -Wstrict-prototypes -Wmissing-prototypes
 CFLAGS+=-Wmissing-declarations -Wshadow -Wpointer-arith -Wcast-qual
 CFLAGS+=-Wsign-compare -Iinclude/kore -I$(OBJDIR) -std=c99 -pedantic
-CFLAGS+=-Wtype-limits -fno-common
+CFLAGS+=-fno-common
 CFLAGS+=-DPREFIX='"$(PREFIX)"' -fstack-protector-all
 
 LDFLAGS+=-rdynamic
@@ -68,8 +68,6 @@ endif
 
 ifneq ("$(NOOPT)", "")
 	CFLAGS+=-O0
-else
-	CFLAGS+=-O2
 endif
 
 ifneq ("$(NOSENDFILE)", "")
