ifneq ($(filter 4.%,$(GCCVERSION)),)
  GCC4=1
endif

LDFLAGS += -Wl,--warn-common

CFLAGS := -g

# Use pipes and not temp files.
CFLAGS += -pipe
# optimize even more
CFLAGS += -O2
# let the type char be unsigned by default
CFLAGS += -funsigned-char
CFLAGS += -fstrict-aliasing
# turn on all common warnings
CFLAGS += -Wall
# turn on extra warnings
CFLAGS += $(if $(GCC4),-Wextra,-W)
# treat warnings as errors
#CFLAGS += -Werror
CFLAGS += -Wchar-subscripts
# warn about undefined preprocessor identifiers
CFLAGS += -Wundef
# warn about local variable shadowing another local variable
CFLAGS += -Wshadow
# warn about casting of pointers to increased alignment requirements
CFLAGS += -Wcast-align
# make string constants const
CFLAGS += -Wwrite-strings
# warn about implicit conversions with side effects
# fgets, calloc and friends take an int, not size_t...
#CFLAGS += -Wconversion
# warn about comparisons between signed and unsigned values
CFLAGS += -Wsign-compare
# warn about unused declared stuff
CFLAGS += -Wunused
# don not warn about unused return value
CFLAGS += -Wno-unused-value
# warn about variable use before initialization
CFLAGS += -Wuninitialized
# warn about pointer arithmetic on void* and function pointers
CFLAGS += -Wpointer-arith
# warn about multiple declarations
CFLAGS += -Wredundant-decls
# warn if the format string is not a string literal
CFLAGS += -Wformat-nonliteral