toolchain/gcc/patches/4.5.0/910-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 @@ -105,6 +105,9 @@
  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 @@ -690,6 +701,12 @@
  33        flag_exceptions = value;
  34        break;
  35
  36 +    case OPT_fhonour_copts:
  37 +      if (c_language == clk_c) {
  38 +       honour_copts++;
  39 +      }
  40 +      break;
  41 +
  42      case OPT_fimplement_inlines:
  43        flag_implement_inlines = value;
  44        break;
  45 @@ -1209,6 +1226,47 @@
  46        return false;
  47      }
  48
  49 +  if (c_language == clk_c) {
  50 +    char *ev = getenv ("GCC_HONOUR_COPTS");
  51 +    int evv;
  52 +    if (ev == NULL)
  53 +      evv = -1;
  54 +    else if ((*ev == '0') || (*ev == '\0'))
  55 +      evv = 0;
  56 +    else if (*ev == '1')
  57 +      evv = 1;
  58 +    else if (*ev == '2')
  59 +      evv = 2;
  60 +    else if (*ev == 's')
  61 +      evv = -1;
  62 +    else {
  63 +      warning (0, "unknown GCC_HONOUR_COPTS value, assuming 1");
  64 +      evv = 1; /* maybe depend this on something like MIRBSD_NATIVE?  */
  65 +    }
  66 +    if (evv == 1) {
  67 +      if (honour_copts == 0) {
  68 +       error ("someone does not honour COPTS at all in lenient mode");
  69 +       return false;
  70 +      } else if (honour_copts != 1) {
  71 +       warning (0, "someone does not honour COPTS correctly, passed %d times",
  72 +        honour_copts);
  73 +      }
  74 +    } else if (evv == 2) {
  75 +      if (honour_copts == 0) {
  76 +       error ("someone does not honour COPTS at all in strict mode");
  77 +       return false;
  78 +      } else if (honour_copts != 1) {
  79 +       error ("someone does not honour COPTS correctly, passed %d times",
  80 +        honour_copts);
  81 +       return false;
  82 +      }
  83 +    } else if (evv == 0) {
  84 +      if (honour_copts != 1)
  85 +       inform (0, "someone does not honour COPTS correctly, passed %d times",
  86 +        honour_copts);
  87 +    }
  88 +  }
  89 +
  90    return true;
  91  }
  92
  93 --- a/gcc/c.opt
  94 +++ b/gcc/c.opt
  95 @@ -215,6 +215,10 @@
  96  C ObjC RejectNegative Warning
  97  This switch is deprecated; use -Werror=implicit-function-declaration instead
  98
  99 +Werror-maybe-reset
 100 +C ObjC C++ ObjC++
 101 +; Documented in common.opt
 102 +
 103  Wfloat-equal
 104  C ObjC C++ ObjC++ Var(warn_float_equal) Warning
 105  Warn if testing floating point numbers for equality
 106 @@ -609,6 +613,9 @@
 107  fhonor-std
 108  C++ ObjC++
 109
 110 +fhonour-copts
 111 +C ObjC C++ ObjC++ RejectNegative
 112 +
 113  fhosted
 114  C ObjC
 115  Assume normal C execution environment
 116 --- a/gcc/common.opt
 117 +++ b/gcc/common.opt
 118 @@ -102,6 +102,10 @@
 119  Common Joined
 120  Treat specified warning as error
 121
 122 +Werror-maybe-reset
 123 +Common
 124 +If environment variable GCC_NO_WERROR is set, act as -Wno-error
 125 +
 126  Wextra
 127  Common Warning
 128  Print extra (possibly unwanted) warnings
 129 @@ -573,6 +577,9 @@
 130  Common Report Var(flag_guess_branch_prob) Optimization
 131  Enable guessing of branch probabilities
 132
 133 +fhonour-copts
 134 +Common RejectNegative
 135 +
 136  ; Nonzero means ignore `#ident' directives.  0 means handle them.
 137  ; Generate position-independent code for executables if possible
 138  ; On SVR4 targets, it also controls whether or not to emit a
 139 --- a/gcc/opts.c
 140 +++ b/gcc/opts.c
 141 @@ -891,8 +891,6 @@
 142    flag_schedule_insns_after_reload = opt2;
 143  #endif
 144    flag_regmove = opt2;
 145 -  flag_strict_aliasing = opt2;
 146 -  flag_strict_overflow = opt2;
 147    flag_reorder_blocks = opt2;
 148    flag_reorder_functions = opt2;
 149    flag_tree_vrp = opt2;
 150 @@ -912,6 +910,9 @@
 151
 152    /* -O3 optimizations.  */
 153    opt3 = (optimize >= 3);
 154 +  flag_strict_aliasing = opt3;
 155 +  flag_strict_overflow = opt3;
 156 +  flag_delete_null_pointer_checks = opt3;
 157    flag_predictive_commoning = opt3;
 158    flag_inline_functions = opt3;
 159    flag_unswitch_loops = opt3;
 160 @@ -1638,6 +1639,17 @@
 161        enable_warning_as_error (arg, value, lang_mask);
 162        break;
 163
 164 +    case OPT_Werror_maybe_reset:
 165 +      {
 166 +       char *ev = getenv ("GCC_NO_WERROR");
 167 +       if ((ev != NULL) && (*ev != '0'))
 168 +         warnings_are_errors = 0;
 169 +      }
 170 +      break;
 171 +
 172 +    case OPT_fhonour_copts:
 173 +      break;
 174 +
 175      case OPT_Wlarger_than_:
 176        /* This form corresponds to -Wlarger-than-.
 177          Kept for backward compatibility.
 178 --- a/gcc/doc/cppopts.texi
 179 +++ b/gcc/doc/cppopts.texi
 180 @@ -164,6 +164,11 @@
 181  Make all warnings into hard errors.  Source code which triggers warnings
 182  will be rejected.
 183
 184 + at item -Werror-maybe-reset
 185 + at opindex Werror-maybe-reset
 186 +Act like @samp{-Wno-error} if the @env{GCC_NO_WERROR} environment
 187 +variable is set to anything other than 0 or empty.
 188 +
 189  @item -Wsystem-headers
 190  @opindex Wsystem-headers
 191  Issue warnings for code in system headers.  These are normally unhelpful
 192 --- a/gcc/doc/invoke.texi
 193 +++ b/gcc/doc/invoke.texi
 194 @@ -234,7 +234,7 @@
 195  -Wconversion  -Wcoverage-mismatch  -Wno-deprecated  @gol
 196  -Wno-deprecated-declarations -Wdisabled-optimization  @gol
 197  -Wno-div-by-zero -Wempty-body  -Wenum-compare -Wno-endif-labels @gol
 198 --Werror  -Werror=* @gol
 199 +-Werror  -Werror=* -Werror-maybe-reset @gol
 200  -Wfatal-errors  -Wfloat-equal  -Wformat  -Wformat=2 @gol
 201  -Wno-format-contains-nul -Wno-format-extra-args -Wformat-nonliteral @gol
 202  -Wformat-security  -Wformat-y2k @gol
 203 @@ -4161,6 +4161,22 @@
 204  @option{-Wall} and by @option{-pedantic}, which can be disabled with
 205  @option{-Wno-pointer-sign}.
 206
 207 + at item -Werror-maybe-reset
 208 + at opindex Werror-maybe-reset
 209 +Act like @samp{-Wno-error} if the @env{GCC_NO_WERROR} environment
 210 +variable is set to anything other than 0 or empty.
 211 +
 212 + at item -fhonour-copts
 213 + at opindex fhonour-copts
 214 +If @env{GCC_HONOUR_COPTS} is set to 1, abort if this option is not
 215 +given at least once, and warn if it is given more than once.
 216 +If @env{GCC_HONOUR_COPTS} is set to 2, abort if this option is not
 217 +given exactly once.
 218 +If @env{GCC_HONOUR_COPTS} is set to 0 or unset, warn if this option
 219 +is not given exactly once.
 220 +The warning is quelled if @env{GCC_HONOUR_COPTS} is set to @samp{s}.
 221 +This flag and environment variable only affect the C language.
 222 +
 223  @item -Wstack-protector
 224  @opindex Wstack-protector
 225  @opindex Wno-stack-protector
 226 @@ -5699,7 +5715,7 @@
 227  second branch or a point immediately following it, depending on whether
 228  the condition is known to be true or false.
 229
 230 -Enabled at levels @option{-O2}, @option{-O3}, @option{-Os}.
 231 +Enabled at levels @option{-O3}.
 232
 233  @item -fsplit-wide-types
 234  @opindex fsplit-wide-types
 235 @@ -5844,7 +5860,7 @@
 236  @option{-fno-delete-null-pointer-checks} to disable this optimization
 237  for programs which depend on that behavior.
 238
 239 -Enabled at levels @option{-O2}, @option{-O3}, @option{-Os}.
 240 +Enabled at levels @option{-O3}.
 241
 242  @item -fexpensive-optimizations
 243  @opindex fexpensive-optimizations
 244 --- a/gcc/java/jvspec.c
 245 +++ b/gcc/java/jvspec.c
 246 @@ -670,6 +670,7 @@
 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      {