toolchain/gcc/patches/linaro/910-mbsd_multi.patch

   1
   2         This patch brings over a few features from MirBSD:
   3         * -fhonour-copts
   4           If this option is not given, it's warned (depending
   5           on environment variables). This is to catch errors
   6           of misbuilt packages which override CFLAGS themselves.
   7         * -Werror-maybe-reset
   8           Has the effect of -Wno-error if GCC_NO_WERROR is
   9           set and not '0', a no-operation otherwise. This is
  10           to be able to use -Werror in "make" but prevent
  11           GNU autoconf generated configure scripts from
  12           freaking out.
  13         * Make -fno-strict-aliasing and -fno-delete-null-pointer-checks
  14           the default for -O2/-Os, because they trigger gcc bugs
  15           and can delete code with security implications.
  16
  17         This patch was authored by Thorsten Glaser <tg at mirbsd.de>
  18         with copyright assignment to the FSF in effect.
  19
  20 --- a/gcc/c-opts.c
  21 +++ b/gcc/c-opts.c
  22 @@ -106,6 +106,9 @@ static size_t deferred_count;
  23  /* Number of deferred options scanned for -include.  */
  24  static size_t include_cursor;
  25
  26 +/* Check if a port honours COPTS.  */
  27 +static int honour_copts = 0;
  28 +
  29  static void set_Wimplicit (int);
  30  static void handle_OPT_d (const char *);
  31  static void set_std_cxx98 (int);
  32 @@ -472,6 +475,9 @@ c_common_handle_option (size_t scode, co
  33        enable_warning_as_error ("implicit-function-declaration", value, CL_C | CL_ObjC);
  34        break;
  35
  36 +    case OPT_Werror_maybe_reset:
  37 +      break;
  38 +
  39      case OPT_Wformat:
  40        set_Wformat (value);
  41        break;
  42 @@ -704,6 +710,12 @@ c_common_handle_option (size_t scode, co
  43        flag_exceptions = value;
  44        break;
  45
  46 +    case OPT_fhonour_copts:
  47 +      if (c_language == clk_c) {
  48 +       honour_copts++;
  49 +      }
  50 +      break;
  51 +
  52      case OPT_fimplement_inlines:
  53        flag_implement_inlines = value;
  54        break;
  55 @@ -1240,6 +1252,47 @@ c_common_init (void)
  56        return false;
  57      }
  58
  59 +  if (c_language == clk_c) {
  60 +    char *ev = getenv ("GCC_HONOUR_COPTS");
  61 +    int evv;
  62 +    if (ev == NULL)
  63 +      evv = -1;
  64 +    else if ((*ev == '0') || (*ev == '\0'))
  65 +      evv = 0;
  66 +    else if (*ev == '1')
  67 +      evv = 1;
  68 +    else if (*ev == '2')
  69 +      evv = 2;
  70 +    else if (*ev == 's')
  71 +      evv = -1;
  72 +    else {
  73 +      warning (0, "unknown GCC_HONOUR_COPTS value, assuming 1");
  74 +      evv = 1; /* maybe depend this on something like MIRBSD_NATIVE?  */
  75 +    }
  76 +    if (evv == 1) {
  77 +      if (honour_copts == 0) {
  78 +       error ("someone does not honour COPTS at all in lenient mode");
  79 +       return false;
  80 +      } else if (honour_copts != 1) {
  81 +       warning (0, "someone does not honour COPTS correctly, passed %d times",
  82 +        honour_copts);
  83 +      }
  84 +    } else if (evv == 2) {
  85 +      if (honour_copts == 0) {
  86 +       error ("someone does not honour COPTS at all in strict mode");
  87 +       return false;
  88 +      } else if (honour_copts != 1) {
  89 +       error ("someone does not honour COPTS correctly, passed %d times",
  90 +        honour_copts);
  91 +       return false;
  92 +      }
  93 +    } else if (evv == 0) {
  94 +      if (honour_copts != 1)
  95 +       inform (0, "someone does not honour COPTS correctly, passed %d times",
  96 +        honour_copts);
  97 +    }
  98 +  }
  99 +
 100    return true;
 101  }
 102
 103 --- a/gcc/c.opt
 104 +++ b/gcc/c.opt
 105 @@ -219,6 +219,10 @@ Werror-implicit-function-declaration
 106  C ObjC RejectNegative Warning
 107  This switch is deprecated; use -Werror=implicit-function-declaration instead
 108
 109 +Werror-maybe-reset
 110 +C ObjC C++ ObjC++
 111 +; Documented in common.opt
 112 +
 113  Wfloat-equal
 114  C ObjC C++ ObjC++ Var(warn_float_equal) Warning
 115  Warn if testing floating point numbers for equality
 116 @@ -637,6 +641,9 @@ C++ ObjC++ Optimization
 117  fhonor-std
 118  C++ ObjC++
 119
 120 +fhonour-copts
 121 +C ObjC C++ ObjC++ RejectNegative
 122 +
 123  fhosted
 124  C ObjC
 125  Assume normal C execution environment
 126 --- a/gcc/common.opt
 127 +++ b/gcc/common.opt
 128 @@ -105,6 +105,10 @@ Werror=
 129  Common Joined
 130  Treat specified warning as error
 131
 132 +Werror-maybe-reset
 133 +Common
 134 +If environment variable GCC_NO_WERROR is set, act as -Wno-error
 135 +
 136  Wextra
 137  Common Var(extra_warnings) Warning
 138  Print extra (possibly unwanted) warnings
 139 @@ -625,6 +629,9 @@ fguess-branch-probability
 140  Common Report Var(flag_guess_branch_prob) Optimization
 141  Enable guessing of branch probabilities
 142
 143 +fhonour-copts
 144 +Common RejectNegative
 145 +
 146  ; Nonzero means ignore `#ident' directives.  0 means handle them.
 147  ; Generate position-independent code for executables if possible
 148  ; On SVR4 targets, it also controls whether or not to emit a
 149 --- a/gcc/opts.c
 150 +++ b/gcc/opts.c
 151 @@ -897,8 +897,6 @@ decode_options (unsigned int argc, const
 152    flag_schedule_insns_after_reload = opt2;
 153  #endif
 154    flag_regmove = opt2;
 155 -  flag_strict_aliasing = opt2;
 156 -  flag_strict_overflow = opt2;
 157    flag_reorder_blocks = opt2;
 158    flag_reorder_functions = opt2;
 159    flag_tree_vrp = opt2;
 160 @@ -920,6 +918,8 @@ decode_options (unsigned int argc, const
 161
 162    /* -O3 optimizations.  */
 163    opt3 = (optimize >= 3);
 164 +  flag_strict_aliasing = opt3;
 165 +  flag_strict_overflow = opt3;
 166    flag_predictive_commoning = opt3;
 167    flag_inline_functions = opt3;
 168    flag_unswitch_loops = opt3;
 169 @@ -1648,6 +1648,17 @@ common_handle_option (size_t scode, cons
 170        enable_warning_as_error (arg, value, lang_mask);
 171        break;
 172
 173 +    case OPT_Werror_maybe_reset:
 174 +      {
 175 +       char *ev = getenv ("GCC_NO_WERROR");
 176 +       if ((ev != NULL) && (*ev != '0'))
 177 +         warnings_are_errors = 0;
 178 +      }
 179 +      break;
 180 +
 181 +    case OPT_fhonour_copts:
 182 +      break;
 183 +
 184      case OPT_Wlarger_than_:
 185        /* This form corresponds to -Wlarger-than-.
 186          Kept for backward compatibility.
 187 --- a/gcc/doc/cppopts.texi
 188 +++ b/gcc/doc/cppopts.texi
 189 @@ -164,6 +164,11 @@ in older programs.  This warning is on b
 190  Make all warnings into hard errors.  Source code which triggers warnings
 191  will be rejected.
 192
 193 + at item -Werror-maybe-reset
 194 + at opindex Werror-maybe-reset
 195 +Act like @samp{-Wno-error} if the @env{GCC_NO_WERROR} environment
 196 +variable is set to anything other than 0 or empty.
 197 +
 198  @item -Wsystem-headers
 199  @opindex Wsystem-headers
 200  Issue warnings for code in system headers.  These are normally unhelpful
 201 --- a/gcc/doc/invoke.texi
 202 +++ b/gcc/doc/invoke.texi
 203 @@ -235,7 +235,7 @@ Objective-C and Objective-C++ Dialects}.
 204  -Wconversion  -Wcoverage-mismatch  -Wno-deprecated  @gol
 205  -Wno-deprecated-declarations -Wdisabled-optimization  @gol
 206  -Wno-div-by-zero -Wdouble-promotion -Wempty-body  -Wenum-compare @gol
 207 --Wno-endif-labels -Werror  -Werror=* @gol
 208 +-Wno-endif-labels -Werror  -Werror=* -Werror-maybe-reset @gol
 209  -Wfatal-errors  -Wfloat-equal  -Wformat  -Wformat=2 @gol
 210  -Wno-format-contains-nul -Wno-format-extra-args -Wformat-nonliteral @gol
 211  -Wformat-security  -Wformat-y2k @gol
 212 @@ -4359,6 +4359,22 @@ This option is only supported for C and
 213  @option{-Wall} and by @option{-pedantic}, which can be disabled with
 214  @option{-Wno-pointer-sign}.
 215
 216 + at item -Werror-maybe-reset
 217 + at opindex Werror-maybe-reset
 218 +Act like @samp{-Wno-error} if the @env{GCC_NO_WERROR} environment
 219 +variable is set to anything other than 0 or empty.
 220 +
 221 + at item -fhonour-copts
 222 + at opindex fhonour-copts
 223 +If @env{GCC_HONOUR_COPTS} is set to 1, abort if this option is not
 224 +given at least once, and warn if it is given more than once.
 225 +If @env{GCC_HONOUR_COPTS} is set to 2, abort if this option is not
 226 +given exactly once.
 227 +If @env{GCC_HONOUR_COPTS} is set to 0 or unset, warn if this option
 228 +is not given exactly once.
 229 +The warning is quelled if @env{GCC_HONOUR_COPTS} is set to @samp{s}.
 230 +This flag and environment variable only affect the C language.
 231 +
 232  @item -Wstack-protector
 233  @opindex Wstack-protector
 234  @opindex Wno-stack-protector
 235 @@ -6112,7 +6128,7 @@ so, the first branch is redirected to ei
 236  second branch or a point immediately following it, depending on whether
 237  the condition is known to be true or false.
 238
 239 -Enabled at levels @option{-O2}, @option{-O3}, @option{-Os}.
 240 +Enabled at levels @option{-O3}.
 241
 242  @item -fsplit-wide-types
 243  @opindex fsplit-wide-types
 244 --- a/gcc/java/jvspec.c
 245 +++ b/gcc/java/jvspec.c
 246 @@ -667,6 +667,7 @@ lang_specific_pre_link (void)
 247       class name.  Append dummy `.c' that can be stripped by set_input so %b
 248       is correct.  */
 249    set_input (concat (main_class_name, "main.c", NULL));
 250 +  putenv ("GCC_HONOUR_COPTS=s"); /* XXX hack!  */
 251    err = do_spec (jvgenmain_spec);
 252    if (err == 0)
 253      {