The configure-based build also has this in addition to -Wall.
Closes https://github.com/curl/curl/pull/1578
endif
CC = $(CROSSPREFIX)gcc
-CFLAGS = -g -O2 -Wall
+CFLAGS = -g -O2 -Wall -W
CFLAGS += -fno-strict-aliasing
ifeq ($(ARCH),w64)
CFLAGS += -m64 -D_AMD64_
endif
CC = $(CROSSPREFIX)gcc
-CFLAGS = $(CURL_CFLAG_EXTRAS) -g -O2 -Wall
+CFLAGS = $(CURL_CFLAG_EXTRAS) -g -O2 -Wall -W
CFLAGS += -fno-strict-aliasing
# comment LDFLAGS below to keep debug info
LDFLAGS = $(CURL_LDFLAG_EXTRAS) $(CURL_LDFLAG_EXTRAS_DLL) -s
endif
CC = $(CROSSPREFIX)gcc
-CFLAGS = $(CURL_CFLAG_EXTRAS) -g -O2 -Wall
+CFLAGS = $(CURL_CFLAG_EXTRAS) -g -O2 -Wall -W
CFLAGS += -fno-strict-aliasing
# comment LDFLAGS below to keep debug info
LDFLAGS = $(CURL_LDFLAG_EXTRAS) $(CURL_LDFLAG_EXTRAS_EXE) -s