toolchain/gcc/patches/4.3.5/910-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 @@ -108,6 +108,9 @@ 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 @@ -462,6 +465,14 @@ 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 +      {
  38 +       char *ev = getenv ("GCC_NO_WERROR");
  39 +       if ((ev != NULL) && (*ev != '0'))
  40 +         cpp_opts->warnings_are_errors = 0;
  41 +      }
  42 +      break;
  43 +
  44      case OPT_Wformat:
  45        set_Wformat (value);
  46        break;
  47 @@ -708,6 +719,12 @@ c_common_handle_option (size_t scode, co
  48        flag_exceptions = value;
  49        break;
  50
  51 +    case OPT_fhonour_copts:
  52 +      if (c_language == clk_c) {
  53 +       honour_copts++;
  54 +      }
  55 +      break;
  56 +
  57      case OPT_fimplement_inlines:
  58        flag_implement_inlines = value;
  59        break;
  60 @@ -1248,6 +1265,47 @@ c_common_init (void)
  61    /* Has to wait until now so that cpplib has its hash table.  */
  62    init_pragma ();
  63
  64 +  if (c_language == clk_c) {
  65 +    char *ev = getenv ("GCC_HONOUR_COPTS");
  66 +    int evv;
  67 +    if (ev == NULL)
  68 +      evv = -1;
  69 +    else if ((*ev == '0') || (*ev == '\0'))
  70 +      evv = 0;
  71 +    else if (*ev == '1')
  72 +      evv = 1;
  73 +    else if (*ev == '2')
  74 +      evv = 2;
  75 +    else if (*ev == 's')
  76 +      evv = -1;
  77 +    else {
  78 +      warning (0, "unknown GCC_HONOUR_COPTS value, assuming 1");
  79 +      evv = 1; /* maybe depend this on something like MIRBSD_NATIVE?  */
  80 +    }
  81 +    if (evv == 1) {
  82 +      if (honour_copts == 0) {
  83 +       error ("someone does not honour COPTS at all in lenient mode");
  84 +       return false;
  85 +      } else if (honour_copts != 1) {
  86 +       warning (0, "someone does not honour COPTS correctly, passed %d times",
  87 +        honour_copts);
  88 +      }
  89 +    } else if (evv == 2) {
  90 +      if (honour_copts == 0) {
  91 +       error ("someone does not honour COPTS at all in strict mode");
  92 +       return false;
  93 +      } else if (honour_copts != 1) {
  94 +       error ("someone does not honour COPTS correctly, passed %d times",
  95 +        honour_copts);
  96 +       return false;
  97 +      }
  98 +    } else if (evv == 0) {
  99 +      if (honour_copts != 1)
 100 +       inform ("someone does not honour COPTS correctly, passed %d times",
 101 +        honour_copts);
 102 +    }
 103 +  }
 104 +
 105    return true;
 106  }
 107
 108 --- a/gcc/c.opt
 109 +++ b/gcc/c.opt
 110 @@ -207,6 +207,10 @@ Werror-implicit-function-declaration
 111  C ObjC RejectNegative Warning
 112  This switch is deprecated; use -Werror=implicit-function-declaration instead
 113
 114 +Werror-maybe-reset
 115 +C ObjC C++ ObjC++
 116 +; Documented in common.opt
 117 +
 118  Wfloat-equal
 119  C ObjC C++ ObjC++ Var(warn_float_equal) Warning
 120  Warn if testing floating point numbers for equality
 121 @@ -590,6 +594,9 @@ C++ ObjC++ Optimization
 122  fhonor-std
 123  C++ ObjC++
 124
 125 +fhonour-copts
 126 +C ObjC C++ ObjC++ RejectNegative
 127 +
 128  fhosted
 129  C ObjC
 130  Assume normal C execution environment
 131 --- a/gcc/common.opt
 132 +++ b/gcc/common.opt
 133 @@ -102,6 +102,10 @@ Werror=
 134  Common Joined
 135  Treat specified warning as error
 136
 137 +Werror-maybe-reset
 138 +Common
 139 +If environment variable GCC_NO_WERROR is set, act as -Wno-error
 140 +
 141  Wextra
 142  Common Warning
 143  Print extra (possibly unwanted) warnings
 144 @@ -528,6 +532,9 @@ fguess-branch-probability
 145  Common Report Var(flag_guess_branch_prob) Optimization
 146  Enable guessing of branch probabilities
 147
 148 +fhonour-copts
 149 +Common RejectNegative
 150 +
 151  ; Nonzero means ignore `#ident' directives.  0 means handle them.
 152  ; Generate position-independent code for executables if possible
 153  ; On SVR4 targets, it also controls whether or not to emit a
 154 --- a/gcc/opts.c
 155 +++ b/gcc/opts.c
 156 @@ -830,9 +830,6 @@ decode_options (unsigned int argc, const
 157        flag_schedule_insns_after_reload = 1;
 158  #endif
 159        flag_regmove = 1;
 160 -      flag_strict_aliasing = 1;
 161 -      flag_strict_overflow = 1;
 162 -      flag_delete_null_pointer_checks = 1;
 163        flag_reorder_blocks = 1;
 164        flag_reorder_functions = 1;
 165        flag_tree_store_ccp = 1;
 166 @@ -853,6 +850,10 @@ decode_options (unsigned int argc, const
 167
 168    if (optimize >= 3)
 169      {
 170 +      flag_strict_aliasing = 1;
 171 +      flag_strict_overflow = 1;
 172 +      flag_delete_null_pointer_checks = 1;
 173 +
 174        flag_predictive_commoning = 1;
 175        flag_inline_functions = 1;
 176        flag_unswitch_loops = 1;
 177 @@ -1444,6 +1445,17 @@ common_handle_option (size_t scode, cons
 178        enable_warning_as_error (arg, value, lang_mask);
 179        break;
 180
 181 +    case OPT_Werror_maybe_reset:
 182 +      {
 183 +       char *ev = getenv ("GCC_NO_WERROR");
 184 +       if ((ev != NULL) && (*ev != '0'))
 185 +         warnings_are_errors = 0;
 186 +      }
 187 +      break;
 188 +
 189 +    case OPT_fhonour_copts:
 190 +      break;
 191 +
 192      case OPT_Wextra:
 193        set_Wextra (value);
 194        break;
 195 --- a/gcc/doc/cppopts.texi
 196 +++ b/gcc/doc/cppopts.texi
 197 @@ -168,6 +168,11 @@ in older programs.  This warning is on b
 198  Make all warnings into hard errors.  Source code which triggers warnings
 199  will be rejected.
 200
 201 + at item -Werror-maybe-reset
 202 + at opindex Werror-maybe-reset
 203 +Act like @samp{-Wno-error} if the @env{GCC_NO_WERROR} environment
 204 +variable is set to anything other than 0 or empty.
 205 +
 206  @item -Wsystem-headers
 207  @opindex Wsystem-headers
 208  Issue warnings for code in system headers.  These are normally unhelpful
 209 --- a/gcc/doc/invoke.texi
 210 +++ b/gcc/doc/invoke.texi
 211 @@ -233,7 +233,7 @@ Objective-C and Objective-C++ Dialects}.
 212  -Wconversion  -Wcoverage-mismatch  -Wno-deprecated-declarations @gol
 213  -Wdisabled-optimization  -Wno-div-by-zero  @gol
 214  -Wempty-body  -Wno-endif-labels @gol
 215 --Werror  -Werror=* @gol
 216 +-Werror  -Werror=* -Werror-maybe-reset @gol
 217  -Wfatal-errors  -Wfloat-equal  -Wformat  -Wformat=2 @gol
 218  -Wno-format-extra-args -Wformat-nonliteral @gol
 219  -Wformat-security  -Wformat-y2k -Wignored-qualifiers @gol
 220 @@ -4031,6 +4031,22 @@ This option is only supported for C and
 221  @option{-Wall} and by @option{-pedantic}, which can be disabled with
 222  @option{-Wno-pointer-sign}.
 223
 224 + at item -Werror-maybe-reset
 225 + at opindex Werror-maybe-reset
 226 +Act like @samp{-Wno-error} if the @env{GCC_NO_WERROR} environment
 227 +variable is set to anything other than 0 or empty.
 228 +
 229 + at item -fhonour-copts
 230 + at opindex fhonour-copts
 231 +If @env{GCC_HONOUR_COPTS} is set to 1, abort if this option is not
 232 +given at least once, and warn if it is given more than once.
 233 +If @env{GCC_HONOUR_COPTS} is set to 2, abort if this option is not
 234 +given exactly once.
 235 +If @env{GCC_HONOUR_COPTS} is set to 0 or unset, warn if this option
 236 +is not given exactly once.
 237 +The warning is quelled if @env{GCC_HONOUR_COPTS} is set to @samp{s}.
 238 +This flag and environment variable only affect the C language.
 239 +
 240  @item -Wstack-protector
 241  @opindex Wstack-protector
 242  @opindex Wno-stack-protector
 243 @@ -5493,7 +5509,7 @@ so, the first branch is redirected to ei
 244  second branch or a point immediately following it, depending on whether
 245  the condition is known to be true or false.
 246
 247 -Enabled at levels @option{-O2}, @option{-O3}, @option{-Os}.
 248 +Enabled at levels @option{-O3}.
 249
 250  @item -fsplit-wide-types
 251  @opindex fsplit-wide-types
 252 @@ -5638,7 +5654,7 @@ safely dereference null pointers.  Use
 253  @option{-fno-delete-null-pointer-checks} to disable this optimization
 254  for programs which depend on that behavior.
 255
 256 -Enabled at levels @option{-O2}, @option{-O3}, @option{-Os}.
 257 +Enabled at levels @option{-O3}.
 258
 259  @item -fexpensive-optimizations
 260  @opindex fexpensive-optimizations
 261 --- a/gcc/java/jvspec.c
 262 +++ b/gcc/java/jvspec.c
 263 @@ -670,6 +670,7 @@ lang_specific_pre_link (void)
 264       class name.  Append dummy `.c' that can be stripped by set_input so %b
 265       is correct.  */
 266    set_input (concat (main_class_name, "main.c", NULL));
 267 +  putenv ("GCC_HONOUR_COPTS=s"); /* XXX hack!  */
 268    err = do_spec (jvgenmain_spec);
 269    if (err == 0)
 270      {