share/mk/warnings.mk

   1 # RCSid:
   2 #       $Id: warnings.mk,v 1.14 2016/04/05 15:58:37 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.
  27 MIN_WARNINGS?= -Wall \
  28         -Wformat \
  29         -Wimplicit \
  30         -Wunused \
  31         -Wuninitialized
  32
  33 LOW_WARNINGS?= ${MIN_WARNINGS} -W -Wstrict-prototypes -Wmissing-prototypes
  34
  35 MEDIUM_WARNINGS?= ${LOW_WARNINGS} -Werror
  36
  37 HIGH_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
  47 EXTRA_WARNINGS?= ${HIGH_WARNINGS} -Wextra
  48
  49 # The two step default makes it easier to test build with different defaults.
  50 DEFAULT_WARNINGS_SET?= MIN
  51 WARNINGS_SET?= ${DEFAULT_WARNINGS_SET}
  52
  53 # There is always someone who wants more...
  54 .if !empty(WARNINGS_XTRAS)
  55 ${WARNINGS_SET}_WARNINGS += ${WARNINGS_XTRAS}
  56 .endif
  57
  58 # If you add sets, besure to list them (you don't have to touch this list).
  59 ALL_WARNINGS_SETS+= MIN LOW MEDIUM HIGH EXTRA
  60
  61 .if !empty(WARNINGS_SET)
  62 .for ws in ${WARNINGS_SET}
  63 .if empty(${ws}_WARNINGS)
  64 .if ${MAKE_VERSION:[1]:C/.*-//} >= 20050530
  65 .BEGIN: _empty_warnings
  66 _empty_warnings: .PHONY
  67 .else
  68 .BEGIN:
  69 .endif
  70         @echo "ERROR: Invalid: WARNINGS_SET=${ws}"
  71         @echo "ERROR: Try one of: ${ALL_WARNINGS_SETS:O:u}"; exit 1
  72
  73 .endif
  74 .endfor
  75 .endif
  76
  77 # Without -O or if we've set -O0 somewhere - to make debugging more effective,
  78 # we need to turn off -Wuninitialized as otherwise we get a warning that
  79 # -Werror turns into an error.  To be safe, set W_uninitialized blank.
  80 _w_cflags= ${CFLAGS} ${CFLAGS_LAST} ${CPPFLAGS}
  81 .if ${_w_cflags:M-O*} == "" || ${_w_cflags:M-O0} != ""
  82 W_uninitialized=
  83 .endif
  84
  85
  86 # .for loops have the [dis]advantage of being evaluated when read,
  87 # so adding to WARNINGS_SET[_${MACHINE_ARCH}] after this file is
  88 # read has no effect.
  89 # Replacing the above .for loops with the WARNINGS+= below solves that
  90 # but tiggers a double free bug in bmake-20040118 and earlier.
  91 # Don't try and read this too fast!
  92 #
  93 # The first :@ "loop" handles multiple sets in WARNINGS_SET
  94 #
  95 # In the second :@ "loop", the ::?= noise sets W_foo?=-Wfoo etc
  96 # which makes it easy to turn off override individual flags
  97 # (see W_uninitialized above).
  98 #
  99 # The last bit expands to ${W_foo_${.TARGET:T}:U${W_foo}}
 100 # which is the bit we ultimately want.  It allows W_* to be set on a
 101 # per target basis.
 102 #
 103 # NOTE: that we force the target extension to be .o
 104 #
 105
 106 # define this once, we use it a couple of times below (hence the doubled $$).
 107 M_warnings_list = @s@$${$$s_WARNINGS}@:O:u:@w@$${$${w:C/-(.)/\1_/}::?=$$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_/}}}}}@
 108
 109 # first a list of warnings from the chosen set
 110 _warnings = ${WARNINGS_SET_${MACHINE_ARCH}:U${WARNINGS_SET}:${M_warnings_list}}
 111 # now a list of all -Wno-* overrides not just those defined by WARNINGS_SET
 112 # since things like -Wall imply lots of others.
 113 # this should be a super-set of the -Wno-* in _warnings, but
 114 # just in case...
 115 _no_warnings = ${_warnings:M-Wno-*} ${ALL_WARNINGS_SETS:${M_warnings_list}:M-Wno-*}
 116 # -Wno-* must follow any others
 117 WARNINGS += ${_warnings:N-Wno-*} ${_no_warnings:O:u}
 118
 119 .ifndef NO_CFLAGS_WARNINGS
 120 # Just ${WARNINGS} should do, but this is more flexible?
 121 CFLAGS+= ${WARNINGS_${.TARGET:T:R}.o:U${WARNINGS}}
 122 .endif
 123
 124 # it is rather silly that g++ blows up on some warning flags
 125 NO_CXX_WARNINGS+= \
 126         implicit \
 127         missing-declarations \
 128         missing-prototypes \
 129         nested-externs \
 130         shadow \
 131         strict-prototypes
 132
 133 .for s in ${SRCS:M*.c*:N*.c:N*h}
 134 .for w in ${NO_CXX_WARNINGS}
 135 W_$w_${s:T:R}.o=
 136 .endfor
 137 .endfor
 138
 139 .endif # _w_cflags