gcc/config/darwin-driver.cc

   1 /* Additional functions for the GCC driver on Darwin native.
   2    Copyright (C) 2006-2023 Free Software Foundation, Inc.
   3    Contributed by Apple Computer Inc.
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 3, or (at your option)
  10 any later version.
  11
  12 GCC is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING3.  If not see
  19 <http://www.gnu.org/licenses/>.  */
  20
  21 #include "config.h"
  22 #include "libiberty.h"
  23 #include "system.h"
  24 #include "coretypes.h"
  25 #include "tm.h"
  26 #include "opts.h"
  27 #include "diagnostic-core.h"
  28
  29 /* Validate a version string (either given on the command line or, perhaps
  30    as MACOSX_DEPLOYMENT_TARGET).
  31
  32    The specs %version-compare() function doesn't accept leading '0' on
  33    numbers so strip them out.  Do sanity checking here too.
  34
  35    Return:
  36      * original string means it was OK and we didn't want to change it.
  37      * new string means it was OK but we rewrote it to avoid possible format
  38      problems.
  39      * NULL means we didn't like what we saw.
  40 */
  41
  42 static const char *
  43 validate_macosx_version_min (const char *version_str)
  44 {
  45   size_t version_len;
  46   unsigned long major, minor = 0, tiny = 0;
  47   char *end;
  48   const char *old_version = version_str;
  49   bool need_rewrite = false;
  50
  51   version_len = strlen (version_str);
  52   if (version_len < 2) /* The minimum would be 11  */
  53     return NULL;
  54
  55   /* Version string must consist of digits and periods only.  */
  56   if (strspn (version_str, "0123456789.") != version_len)
  57     return NULL;
  58
  59   if (!ISDIGIT (version_str[0]) || !ISDIGIT (version_str[version_len - 1]))
  60     return NULL;
  61
  62   if (version_str[0] == '0')
  63     need_rewrite = true;
  64
  65   major = strtoul (version_str, &end, 10);
  66
  67   /* macOS 10, 11, and 12 are known. clang accepts up to 99.  */
  68   if (major < 10 || major > 99)
  69     return NULL;
  70
  71   /* Skip a separating period, if there's one.  */
  72   version_str = end + ((*end == '.') ? 1 : 0);
  73
  74   if (major > 10 && *end != '\0' && !ISDIGIT (version_str[0]))
  75      /* For macOS 11+, we allow just the major number, but if the minor is
  76         there it must be numeric.  */
  77     return NULL;
  78   else if (major > 10 && *end == '\0')
  79     /* We will rewrite 11 =>  11.0.0.  */
  80     need_rewrite = true;
  81   else if (major == 10 && (*end == '\0' || !ISDIGIT (version_str[0])))
  82     /* Otherwise, minor version components must be present and numeric.  */
  83     return NULL;
  84
  85   /* If we have one or more leading zeros on a component, then rewrite the
  86      version string.  */
  87   if (*end != '\0' && version_str[0] == '0' && version_str[1] != '\0'
  88       && version_str[1] != '.')
  89     need_rewrite = true;
  90
  91   minor = strtoul (version_str, &end, 10);
  92   version_str = end + ((*end == '.') ? 1 : 0);
  93   if (minor > 99)
  94     return NULL;
  95
  96   /* If 'tiny' is present it must be numeric.  */
  97   if (*end != '\0' && !ISDIGIT (version_str[0]))
  98     return NULL;
  99
 100   /* If we have one or more leading zeros on a component, then rewrite the
 101      version string.  */
 102   if (*end != '\0' && version_str[0] == '0'
 103       && version_str[1] != '\0')
 104     need_rewrite = true;
 105
 106   tiny = strtoul (version_str, &end, 10);
 107   if (tiny > 99)
 108     return NULL;
 109
 110   /* Version string must contain no more than three tokens.  */
 111   if (*end != '\0')
 112     return NULL;
 113
 114   if (need_rewrite)
 115     {
 116       char *new_version;
 117       asprintf (&new_version, "%2lu.%lu.%lu", major, minor, tiny);
 118       return new_version;
 119     }
 120
 121   return old_version;
 122 }
 123
 124 #ifndef CROSS_DIRECTORY_STRUCTURE
 125 #include <sys/sysctl.h>
 126 #include "xregex.h"
 127
 128 /* Determine the version of the running OS.
 129    We only look at the first two components (ignoring the patch one) and
 130    report NN.MM.0 where NN is currently either 10 or 11 and MM is the OS
 131    minor release number.
 132    If we can't parse what the kernel gives us, warn the user, and do nothing.  */
 133
 134 static char *
 135 darwin_find_version_from_kernel (void)
 136 {
 137   char osversion[32];
 138   size_t osversion_len = sizeof (osversion) - 1;
 139   static int osversion_name[2] = { CTL_KERN, KERN_OSRELEASE };
 140   int major_vers;
 141   char * version_p;
 142   char * new_flag;
 143
 144   if (sysctl (osversion_name, ARRAY_SIZE (osversion_name), osversion,
 145               &osversion_len, NULL, 0) == -1)
 146     {
 147       warning (0, "%<sysctl%> for %<kern.osversion%> failed: %m");
 148       return NULL;
 149     }
 150
 151   /* Try to parse the first two parts of the OS version number.  Warn
 152      user and return if it doesn't make sense.  */
 153   if (! ISDIGIT (osversion[0]))
 154     goto parse_failed;
 155   major_vers = osversion[0] - '0';
 156   version_p = osversion + 1;
 157   if (ISDIGIT (*version_p))
 158     major_vers = major_vers * 10 + (*version_p++ - '0');
 159   if (*version_p++ != '.')
 160     goto parse_failed;
 161
 162   /* Darwin20 sees a transition to macOS 11.  In this, it seems that the
 163      mapping to macOS minor version and patch level is now always 0, 0
 164      (at least for macOS 11 and 12).  */
 165   if (major_vers >= 20)
 166     {
 167       /* Apple clang doesn't include the minor version or the patch level
 168          in the object file, nor does it pass it to ld  */
 169       asprintf (&new_flag, "%d.00.00", major_vers - 9);
 170     }
 171   else if (major_vers - 4 <= 4)
 172     /* On 10.4 and earlier, the old linker is used which does not
 173        support three-component system versions.
 174        FIXME: we should not assume this - a newer linker could be used.  */
 175     asprintf (&new_flag, "10.%d", major_vers - 4);
 176   else
 177     /* Although the newer linker supports three-component system
 178        versions, there's no guarantee that the minor version component
 179        of the kernel and the system are the same. Apple's clang always
 180        uses 0 as the minor version: do the same.  */
 181     asprintf (&new_flag, "10.%d.0", major_vers - 4);
 182
 183   return new_flag;
 184
 185  parse_failed:
 186   warning (0, "could not understand %<kern.osversion%> %q.*s",
 187            (int) osversion_len, osversion);
 188   return NULL;
 189 }
 190 #endif
 191
 192 /* When running on a Darwin system and using that system's headers and
 193    libraries, default the -mmacosx-version-min flag to be the version
 194    of the system on which the compiler is running.
 195
 196    When building cross or native cross compilers, default to the OSX
 197    version of the target (as provided by the most specific target header
 198    included in tm.h).  This may be overidden by setting the flag explicitly
 199    (or by the MACOSX_DEPLOYMENT_TARGET environment).  */
 200
 201 static const char *
 202 darwin_default_min_version (void)
 203 {
 204   /* Try to retrieve the deployment target from the environment.  */
 205   const char *new_flag = getenv ("MACOSX_DEPLOYMENT_TARGET");
 206
 207   /* Apparently, an empty string for MACOSX_DEPLOYMENT_TARGET means
 208      "use the default".  Or, possibly "use 10.1".  We choose
 209      to ignore the environment variable, as if it was never set.  */
 210   if (new_flag == NULL || new_flag[0] == 0)
 211 #ifndef CROSS_DIRECTORY_STRUCTURE
 212     /* Try to find the version from the kernel, if we fail - we print a
 213        message and give up.  */
 214     new_flag = darwin_find_version_from_kernel ();
 215 #else
 216     /* For cross-compilers, default to a minimum version determined by
 217        the configuration. */
 218     new_flag = DEF_MIN_OSX_VERSION;
 219 #endif /* CROSS_DIRECTORY_STRUCTURE */
 220
 221   if (new_flag != NULL)
 222     {
 223       const char *checked = validate_macosx_version_min (new_flag);
 224       if (checked == NULL)
 225         {
 226           warning (0, "could not understand version %qs", new_flag);
 227           return NULL;
 228         }
 229       new_flag = xstrndup (checked, strlen (checked));
 230     }
 231   return new_flag;
 232 }
 233
 234 /* See if we can find the sysroot from the SDKROOT environment variable.  */
 235
 236 static const char *
 237 maybe_get_sysroot_from_sdkroot ()
 238 {
 239   const char *maybe_sysroot = getenv ("SDKROOT");
 240
 241   /* We'll use the same rules as the clang driver, for compatibility.
 242      1) The path must be absolute
 243      2) Ignore "/", that is the default anyway and we do not want the
 244         sysroot semantics to be applied to it.
 245      3) It must exist (actually, we'll check it's readable too).  */
 246
 247    if (maybe_sysroot  == NULL
 248        || *maybe_sysroot != '/'
 249        || strlen (maybe_sysroot) == 1
 250        || access (maybe_sysroot, R_OK) == -1)
 251     return NULL;
 252
 253   return xstrndup (maybe_sysroot, strlen (maybe_sysroot));
 254 }
 255
 256 /* Handle the deduction of m32/m64 from -arch flags and the interactions
 257    between them (i.e. try to warn a user who thinks that they have a driver
 258    that can produce multi-slice "FAT" outputs with more than one arch).
 259    Default the -mmacosx-version-min flag, which requires a system call on
 260    native hosts.  */
 261
 262 void
 263 darwin_driver_init (unsigned int *decoded_options_count,
 264                     struct cl_decoded_option **decoded_options)
 265 {
 266   unsigned int i;
 267   bool seenX86 = false;
 268   bool seenX86_64 = false;
 269   bool seenPPC = false;
 270   bool seenPPC64 = false;
 271   bool seenM32 = false;
 272   bool seenM64 = false;
 273   bool appendM32 = false;
 274   bool appendM64 = false;
 275   const char *vers_string = NULL;
 276   bool seen_version_min = false;
 277   bool seen_sysroot_p = false;
 278   bool noexport_p = true;
 279
 280   for (i = 1; i < *decoded_options_count; i++)
 281     {
 282       if ((*decoded_options)[i].errors & CL_ERR_MISSING_ARG)
 283         continue;
 284
 285       switch ((*decoded_options)[i].opt_index)
 286         {
 287         case OPT_arch:
 288           /* Support provision of a single -arch xxxx flag as a means of
 289              specifying the sub-target/multi-lib.  Translate this into -m32/64
 290              as appropriate.  */
 291           if (!strcmp ((*decoded_options)[i].arg, "i386"))
 292             seenX86 = true;
 293           else if (!strcmp ((*decoded_options)[i].arg, "x86_64"))
 294             seenX86_64 = true;
 295           else if (!strcmp ((*decoded_options)[i].arg, "ppc"))
 296             seenPPC = true;
 297           else if (!strcmp ((*decoded_options)[i].arg, "ppc64"))
 298             seenPPC64 = true;
 299           else
 300             error ("this compiler does not support %qs",
 301                    (*decoded_options)[i].arg);
 302           /* Now we've examined it, drop the -arch arg.  */
 303           if (*decoded_options_count > i) {
 304             memmove (*decoded_options + i,
 305                      *decoded_options + i + 1,
 306                      ((*decoded_options_count - i - 1)
 307                       * sizeof (struct cl_decoded_option)));
 308           }
 309           --i;
 310           --*decoded_options_count;
 311           break;
 312
 313         case OPT_m32:
 314           seenM32 = true;
 315           break;
 316
 317         case OPT_m64:
 318           seenM64 = true;
 319           break;
 320
 321         case OPT_mmacosx_version_min_:
 322           seen_version_min = true;
 323           vers_string =
 324             validate_macosx_version_min ((*decoded_options)[i].arg);
 325           if (vers_string == NULL)
 326             warning (0, "%qs is not valid for %<-mmacosx-version-min%>",
 327                      (*decoded_options)[i].arg);
 328           else if (vers_string == (*decoded_options)[i].arg)
 329             vers_string = xstrndup ((*decoded_options)[i].arg, 32);
 330           /* Now we've examined it, and verified/re-written, put it to
 331              one side and append later.  */
 332           if (*decoded_options_count > i) {
 333             memmove (*decoded_options + i,
 334                      *decoded_options + i + 1,
 335                      ((*decoded_options_count - i - 1)
 336                       * sizeof (struct cl_decoded_option)));
 337           }
 338           --i;
 339           --*decoded_options_count;
 340           break;
 341
 342         case OPT__sysroot_:
 343         case OPT_isysroot:
 344           seen_sysroot_p = true;
 345           break;
 346
 347         case OPT_Xlinker:
 348         case OPT_Wl_:
 349           gcc_checking_assert ((*decoded_options)[i].arg);
 350           if (startswith ((*decoded_options)[i].arg, "-exported_symbol"))
 351             noexport_p = false;
 352           break;
 353
 354         default:
 355           break;
 356         }
 357     }
 358
 359   /* Turn -arch xxxx into the appropriate -m32/-m64 flag.
 360      If the User tried to specify multiple arch flags (which is possible with
 361      some Darwin compilers) warn that this mode is not supported by this
 362      compiler.  We take arch specifiers that agree with the default multilib
 363      as the first choice and reject others.  */
 364   /* TODO: determine if these warnings would better be errors.  */
 365 #if DARWIN_X86
 366   if (seenPPC || seenPPC64)
 367     warning (0, "this compiler does not support PowerPC"
 368                 " (%<-arch%> option ignored)");
 369   if (seenX86)
 370     {
 371       if (seenX86_64 || seenM64)
 372         {
 373           const char *op = (seenX86_64? "-arch x86_64": "-m64");
 374           warning (0, "%qs conflicts with %<-arch i386%> (%qs ignored)",
 375                    op, op);
 376         }
 377       if (! seenM32) /* Add -m32 if the User didn't. */
 378         appendM32 = true;
 379     }
 380   else if (seenX86_64)
 381     {
 382       if (seenM32)
 383         warning (0, "%<-m32%> conflicts with %<-arch x86_64%>"
 384                     " (%<-m32%> ignored)");
 385       if (! seenM64) /* Add -m64 if the User didn't. */
 386         appendM64 = true;
 387     }
 388 #elif DARWIN_PPC
 389   if (seenX86 || seenX86_64)
 390     warning (0, "this compiler does not support x86"
 391                 " (%<-arch%> option ignored)");
 392   if (seenPPC)
 393     {
 394       if (seenPPC64 || seenM64)
 395         {
 396           const char *op = (seenPPC64? "-arch ppc64": "-m64");
 397           warning (0, "%qs conflicts with %<-arch ppc%> (%qs ignored)",
 398                    op, op);
 399         }
 400       if (! seenM32) /* Add -m32 if the User didn't. */
 401         appendM32 = true;
 402     }
 403   else if (seenPPC64)
 404     {
 405       if (seenM32)
 406         warning (0, "%<-m32%> conflicts with %<-arch ppc64%>"
 407                     " (%<-m32%> ignored)");
 408       if (! seenM64) /* Add -m64 if the User didn't. */
 409         appendM64 = true;
 410     }
 411 #endif
 412
 413   /* If there is nothing else on the command line, do not add sysroot etc.  */
 414   if (*decoded_options_count <= 1)
 415     return;
 416
 417   if (appendM32 || appendM64)
 418     {
 419       ++*decoded_options_count;
 420       *decoded_options = XRESIZEVEC (struct cl_decoded_option,
 421                                      *decoded_options,
 422                                      *decoded_options_count);
 423       generate_option (appendM32 ? OPT_m32 : OPT_m64, NULL, 1, CL_DRIVER,
 424                        &(*decoded_options)[*decoded_options_count - 1]);
 425     }
 426
 427   if (!seen_sysroot_p)
 428     {
 429       /* We will pick up an SDKROOT if we didn't specify a sysroot and treat
 430          it as overriding any configure-time --with-sysroot.  */
 431        const char *sdkroot = maybe_get_sysroot_from_sdkroot ();
 432        if (sdkroot)
 433         {
 434           ++*decoded_options_count;
 435           *decoded_options = XRESIZEVEC (struct cl_decoded_option,
 436                                          *decoded_options,
 437                                          *decoded_options_count);
 438           generate_option (OPT__sysroot_, sdkroot, 1, CL_DRIVER,
 439                            &(*decoded_options)[*decoded_options_count - 1]);
 440         }
 441     }
 442
 443   /* We will need to know the OS X version we're trying to build for here
 444      so that we can figure out the mechanism and source for the sysroot to
 445      be used.  */
 446   if (!seen_version_min)
 447     /* Not set by the User, try to figure it out.  */
 448     vers_string = darwin_default_min_version ();
 449
 450   /* Create and push a cleaned up version, plus the major version for
 451      assemblers and other cases that need it.  */
 452   if (vers_string != NULL)
 453     {
 454        ++*decoded_options_count;
 455        *decoded_options = XRESIZEVEC (struct cl_decoded_option,
 456                                       *decoded_options,
 457                                       *decoded_options_count);
 458       generate_option (OPT_mmacosx_version_min_, vers_string, 1, CL_DRIVER,
 459                        &(*decoded_options)[*decoded_options_count - 1]);
 460
 461       char *asm_major = NULL;
 462       const char *first_period = strchr(vers_string, '.');
 463       if (first_period != NULL)
 464         {
 465           const char *second_period = strchr(first_period+1, '.');
 466           if (second_period  != NULL)
 467             asm_major = xstrndup (vers_string, second_period-vers_string);
 468           else
 469             asm_major = xstrdup (vers_string);
 470         }
 471       /* Else we appear to have a weird macosx version with no major number.
 472          Punt on this for now.  */
 473       if (asm_major != NULL)
 474         {
 475           ++*decoded_options_count;
 476           *decoded_options = XRESIZEVEC (struct cl_decoded_option,
 477                                          *decoded_options,
 478                                          *decoded_options_count);
 479           generate_option (OPT_asm_macosx_version_min_, asm_major, 1, CL_DRIVER,
 480                           &(*decoded_options)[*decoded_options_count - 1]);
 481         }
 482     }
 483
 484   if (noexport_p)
 485     {
 486       ++*decoded_options_count;
 487       *decoded_options = XRESIZEVEC (struct cl_decoded_option,
 488                                      *decoded_options,
 489                                      *decoded_options_count);
 490       generate_option (OPT_nodefaultexport, NULL, 1, CL_DRIVER,
 491                        &(*decoded_options)[*decoded_options_count - 1]);
 492     }
 493 }