xref: /freebsd/contrib/bmake/mk/warnings.mk (revision d9f0ce31900a48d1a2bfc1c8c86f79d1e831451a)
1# RCSid:
2#	$Id: warnings.mk,v 1.9 2016/02/20 02:00:58 sjg Exp $
3#
4#	@(#) Copyright (c) 2002, Simon J. Gerraty
5#
6#	This file is provided in the hope that it will
7#	be of use.  There is absolutely NO WARRANTY.
8#	Permission to copy, redistribute or otherwise
9#	use this file is hereby granted provided that
10#	the above copyright notice and this notice are
11#	left intact.
12#
13#	Please send copies of changes and bug-fixes to:
14#	sjg@crufty.net
15#
16
17.ifndef _w_cflags
18# make sure we get the behavior we expect
19.MAKE.SAVE_DOLLARS = no
20
21# Any number of warnings sets can be added.
22.-include "warnings-sets.mk"
23
24# Modest defaults - put more elaborate sets in warnings-sets.mk
25# -Wunused  etc are here so you can set
26# W_unused=-Wno-unused etc.
27MIN_WARNINGS?= -Wall \
28	-Wformat \
29	-Wimplicit \
30	-Wunused \
31	-Wuninitialized
32
33LOW_WARNINGS?= ${MIN_WARNINGS} -W -Wstrict-prototypes -Wmissing-prototypes
34
35MEDIUM_WARNINGS?= ${LOW_WARNINGS} -Werror
36
37HIGH_WARNINGS?= ${MEDIUM_WARNINGS} \
38	-Wcast-align \
39	-Wcast-qual \
40	-Wparentheses \
41	-Wpointer-arith \
42	-Wmissing-declarations \
43	-Wreturn-type \
44	-Wswitch \
45	-Wwrite-strings
46
47EXTRA_WARNINGS?= ${HIGH_WARNINGS} -Wextra
48
49# The two step default makes it easier to test build with different defaults.
50DEFAULT_WARNINGS_SET?= MIN
51WARNINGS_SET?= ${DEFAULT_WARNINGS_SET}
52
53# If you add sets, besure to list them (you don't have to touch this list).
54ALL_WARNINGS_SETS+= MIN LOW MEDIUM HIGH EXTRA
55
56.if !empty(WARNINGS_SET)
57.for ws in ${WARNINGS_SET}
58.if empty(${ws}_WARNINGS)
59.if ${MAKE_VERSION:[1]:C/.*-//} >= 20050530
60.BEGIN:	_empty_warnings
61_empty_warnings: .PHONY
62.else
63.BEGIN:
64.endif
65	@echo "ERROR: Invalid: WARNINGS_SET=${ws}"
66	@echo "ERROR: Try one of: ${ALL_WARNINGS_SETS:O:u}"; exit 1
67
68.endif
69.endfor
70.endif
71
72# Without -O or if we've set -O0 somewhere - to make debugging more effective,
73# we need to turn off -Wuninitialized as otherwise we get a warning that
74# -Werror turns into an error.  To be safe, set W_uninitialized blank.
75_w_cflags:= ${CFLAGS} ${CPPFLAGS}
76.if ${_w_cflags:M-O*} == "" || ${_w_cflags:M-O0} != ""
77W_uninitialized=
78.endif
79
80
81# .for loops have the [dis]advantage of being evaluated when read,
82# so adding to WARNINGS_SET[_${MACHINE_ARCH}] after this file is
83# read has no effect.
84# Replacing the above .for loops with the WARNINGS+= below solves that
85# but tiggers a double free bug in bmake-20040118 and earlier.
86# Don't try and read this too fast!
87#
88# The first :@ "loop" handles multiple sets in WARNINGS_SET
89#
90# In the second :@ "loop", the ::?= noise sets W_foo?=-Wfoo etc
91# which makes it easy to turn off override individual flags
92# (see W_uninitialized above).
93#
94# The last bit expands to ${W_foo_${.TARGET:T}:U${W_foo}}
95# which is the bit we ultimately want.  It allows W_* to be set on a
96# per target basis.
97#
98# NOTE: that we force the target extension to be .o
99#
100
101# define this once, we use it a couple of times below (hence the doubled $$).
102M_warnings_list = @s@$${$$s_WARNINGS}@:O:u:@w@$${$${w:C/-(.)/\1_/}::?=$$w} $${$${w:C/-(.)/\1_/}_${MACHINE_ARCH}_${.TARGET:T:R}.o:U$${$${w:C/-(.)/\1_/}_${.TARGET:T:R}.o:U$${$${w:C/-(.)/\1_/}_${MACHINE_ARCH}:U$${$${w:C/-(.)/\1_/}}}}}@
103
104# first a list of warnings from the chosen set
105_warnings = ${WARNINGS_SET_${MACHINE_ARCH}:U${WARNINGS_SET}:${M_warnings_list}}
106# now a list of all -Wno-* overrides not just those defined by WARNINGS_SET
107# since things like -Wall imply lots of others.
108# this should be a super-set of the -Wno-* in _warnings, but
109# just in case...
110_no_warnings = ${_warnings:M-Wno-*} ${ALL_WARNINGS_SETS:${M_warnings_list}:M-Wno-*}
111# -Wno-* must follow any others
112WARNINGS += ${_warnings:N-Wno-*} ${_no_warnings:O:u}
113
114.ifndef NO_CFLAGS_WARNINGS
115# Just ${WARNINGS} should do, but this is more flexible?
116CFLAGS+= ${WARNINGS_${.TARGET:T:R}.o:U${WARNINGS}}
117.endif
118
119# it is rather silly that g++ blows up on some warning flags
120NO_CXX_WARNINGS+= \
121	missing-declarations \
122	missing-prototypes \
123	nested-externs \
124	shadow \
125	strict-prototypes
126
127.for s in ${SRCS:M*.c*:N*.c:N*h}
128.for w in ${NO_CXX_WARNINGS}
129W_$w_${s:T:R}.o=
130.endfor
131.endfor
132
133.endif # _w_cflags
134