lld/MinGW/Driver.cpp

   1 //===- MinGW/Driver.cpp ---------------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // MinGW is a GNU development environment for Windows. It consists of GNU
  10 // tools such as GCC and GNU ld. Unlike Cygwin, there's no POSIX-compatible
  11 // layer, as it aims to be a native development toolchain.
  12 //
  13 // lld/MinGW is a drop-in replacement for GNU ld/MinGW.
  14 //
  15 // Being a native development tool, a MinGW linker is not very different from
  16 // Microsoft link.exe, so a MinGW linker can be implemented as a thin wrapper
  17 // for lld/COFF. This driver takes Unix-ish command line options, translates
  18 // them to Windows-ish ones, and then passes them to lld/COFF.
  19 //
  20 // When this driver calls the lld/COFF driver, it passes a hidden option
  21 // "-lldmingw" along with other user-supplied options, to run the lld/COFF
  22 // linker in "MinGW mode".
  23 //
  24 // There are subtle differences between MS link.exe and GNU ld/MinGW, and GNU
  25 // ld/MinGW implements a few GNU-specific features. Such features are directly
  26 // implemented in lld/COFF and enabled only when the linker is running in MinGW
  27 // mode.
  28 //
  29 //===----------------------------------------------------------------------===//
  30
  31 #include "lld/Common/Driver.h"
  32 #include "lld/Common/CommonLinkerContext.h"
  33 #include "lld/Common/ErrorHandler.h"
  34 #include "lld/Common/Memory.h"
  35 #include "lld/Common/Version.h"
  36 #include "llvm/ADT/ArrayRef.h"
  37 #include "llvm/ADT/StringExtras.h"
  38 #include "llvm/ADT/StringRef.h"
  39 #include "llvm/Option/Arg.h"
  40 #include "llvm/Option/ArgList.h"
  41 #include "llvm/Option/Option.h"
  42 #include "llvm/Support/CommandLine.h"
  43 #include "llvm/Support/FileSystem.h"
  44 #include "llvm/Support/Path.h"
  45 #include "llvm/TargetParser/Host.h"
  46 #include "llvm/TargetParser/Triple.h"
  47 #include <optional>
  48
  49 #if !defined(_MSC_VER) && !defined(__MINGW32__)
  50 #include <unistd.h>
  51 #endif
  52
  53 using namespace lld;
  54 using namespace llvm::opt;
  55 using namespace llvm;
  56
  57 // Create OptTable
  58 enum {
  59   OPT_INVALID = 0,
  60 #define OPTION(...) LLVM_MAKE_OPT_ID(__VA_ARGS__),
  61 #include "Options.inc"
  62 #undef OPTION
  63 };
  64
  65 // Create prefix string literals used in Options.td
  66 #define PREFIX(NAME, VALUE)                                                    \
  67   static constexpr llvm::StringLiteral NAME##_init[] = VALUE;                  \
  68   static constexpr llvm::ArrayRef<llvm::StringLiteral> NAME(                   \
  69       NAME##_init, std::size(NAME##_init) - 1);
  70 #include "Options.inc"
  71 #undef PREFIX
  72
  73 // Create table mapping all options defined in Options.td
  74 static constexpr opt::OptTable::Info infoTable[] = {
  75 #define OPTION(PREFIX, NAME, ID, KIND, GROUP, ALIAS, ALIASARGS, FLAGS,         \
  76                VISIBILITY, PARAM, HELPTEXT, METAVAR, VALUES)                   \
  77   {PREFIX,      NAME,        HELPTEXT,                                         \
  78    METAVAR,     OPT_##ID,    opt::Option::KIND##Class,                         \
  79    PARAM,       FLAGS,       VISIBILITY,                                       \
  80    OPT_##GROUP, OPT_##ALIAS, ALIASARGS,                                        \
  81    VALUES},
  82 #include "Options.inc"
  83 #undef OPTION
  84 };
  85
  86 namespace {
  87 class MinGWOptTable : public opt::GenericOptTable {
  88 public:
  89   MinGWOptTable() : opt::GenericOptTable(infoTable, false) {}
  90   opt::InputArgList parse(ArrayRef<const char *> argv);
  91 };
  92 } // namespace
  93
  94 static void printHelp(const char *argv0) {
  95   MinGWOptTable().printHelp(
  96       lld::outs(), (std::string(argv0) + " [options] file...").c_str(), "lld",
  97       false /*ShowHidden*/, true /*ShowAllAliases*/);
  98   lld::outs() << "\n";
  99 }
 100
 101 static cl::TokenizerCallback getQuotingStyle() {
 102   if (Triple(sys::getProcessTriple()).getOS() == Triple::Win32)
 103     return cl::TokenizeWindowsCommandLine;
 104   return cl::TokenizeGNUCommandLine;
 105 }
 106
 107 opt::InputArgList MinGWOptTable::parse(ArrayRef<const char *> argv) {
 108   unsigned missingIndex;
 109   unsigned missingCount;
 110
 111   SmallVector<const char *, 256> vec(argv.data(), argv.data() + argv.size());
 112   cl::ExpandResponseFiles(saver(), getQuotingStyle(), vec);
 113   opt::InputArgList args = this->ParseArgs(vec, missingIndex, missingCount);
 114
 115   if (missingCount)
 116     error(StringRef(args.getArgString(missingIndex)) + ": missing argument");
 117   for (auto *arg : args.filtered(OPT_UNKNOWN))
 118     error("unknown argument: " + arg->getAsString(args));
 119   return args;
 120 }
 121
 122 // Find a file by concatenating given paths.
 123 static std::optional<std::string> findFile(StringRef path1,
 124                                            const Twine &path2) {
 125   SmallString<128> s;
 126   sys::path::append(s, path1, path2);
 127   if (sys::fs::exists(s))
 128     return std::string(s);
 129   return std::nullopt;
 130 }
 131
 132 // This is for -lfoo. We'll look for libfoo.dll.a or libfoo.a from search paths.
 133 static std::string
 134 searchLibrary(StringRef name, ArrayRef<StringRef> searchPaths, bool bStatic) {
 135   if (name.starts_with(":")) {
 136     for (StringRef dir : searchPaths)
 137       if (std::optional<std::string> s = findFile(dir, name.substr(1)))
 138         return *s;
 139     error("unable to find library -l" + name);
 140     return "";
 141   }
 142
 143   for (StringRef dir : searchPaths) {
 144     if (!bStatic) {
 145       if (std::optional<std::string> s = findFile(dir, "lib" + name + ".dll.a"))
 146         return *s;
 147       if (std::optional<std::string> s = findFile(dir, name + ".dll.a"))
 148         return *s;
 149     }
 150     if (std::optional<std::string> s = findFile(dir, "lib" + name + ".a"))
 151       return *s;
 152     if (std::optional<std::string> s = findFile(dir, name + ".lib"))
 153       return *s;
 154     if (!bStatic) {
 155       if (std::optional<std::string> s = findFile(dir, "lib" + name + ".dll"))
 156         return *s;
 157       if (std::optional<std::string> s = findFile(dir, name + ".dll"))
 158         return *s;
 159     }
 160   }
 161   error("unable to find library -l" + name);
 162   return "";
 163 }
 164
 165 namespace lld {
 166 namespace coff {
 167 bool link(ArrayRef<const char *> argsArr, llvm::raw_ostream &stdoutOS,
 168           llvm::raw_ostream &stderrOS, bool exitEarly, bool disableOutput);
 169 }
 170
 171 namespace mingw {
 172 // Convert Unix-ish command line arguments to Windows-ish ones and
 173 // then call coff::link.
 174 bool link(ArrayRef<const char *> argsArr, llvm::raw_ostream &stdoutOS,
 175           llvm::raw_ostream &stderrOS, bool exitEarly, bool disableOutput) {
 176   auto *ctx = new CommonLinkerContext;
 177   ctx->e.initialize(stdoutOS, stderrOS, exitEarly, disableOutput);
 178
 179   MinGWOptTable parser;
 180   opt::InputArgList args = parser.parse(argsArr.slice(1));
 181
 182   if (errorCount())
 183     return false;
 184
 185   if (args.hasArg(OPT_help)) {
 186     printHelp(argsArr[0]);
 187     return true;
 188   }
 189
 190   // A note about "compatible with GNU linkers" message: this is a hack for
 191   // scripts generated by GNU Libtool 2.4.6 (released in February 2014 and
 192   // still the newest version in March 2017) or earlier to recognize LLD as
 193   // a GNU compatible linker. As long as an output for the -v option
 194   // contains "GNU" or "with BFD", they recognize us as GNU-compatible.
 195   if (args.hasArg(OPT_v) || args.hasArg(OPT_version))
 196     message(getLLDVersion() + " (compatible with GNU linkers)");
 197
 198   // The behavior of -v or --version is a bit strange, but this is
 199   // needed for compatibility with GNU linkers.
 200   if (args.hasArg(OPT_v) && !args.hasArg(OPT_INPUT) && !args.hasArg(OPT_l))
 201     return true;
 202   if (args.hasArg(OPT_version))
 203     return true;
 204
 205   if (!args.hasArg(OPT_INPUT) && !args.hasArg(OPT_l)) {
 206     error("no input files");
 207     return false;
 208   }
 209
 210   std::vector<std::string> linkArgs;
 211   auto add = [&](const Twine &s) { linkArgs.push_back(s.str()); };
 212
 213   add("lld-link");
 214   add("-lldmingw");
 215
 216   if (auto *a = args.getLastArg(OPT_entry)) {
 217     StringRef s = a->getValue();
 218     if (args.getLastArgValue(OPT_m) == "i386pe" && s.starts_with("_"))
 219       add("-entry:" + s.substr(1));
 220     else
 221       add("-entry:" + s);
 222   }
 223
 224   if (args.hasArg(OPT_major_os_version, OPT_minor_os_version,
 225                   OPT_major_subsystem_version, OPT_minor_subsystem_version)) {
 226     StringRef majOSVer = args.getLastArgValue(OPT_major_os_version, "6");
 227     StringRef minOSVer = args.getLastArgValue(OPT_minor_os_version, "0");
 228     StringRef majSubSysVer = "6";
 229     StringRef minSubSysVer = "0";
 230     StringRef subSysName = "default";
 231     StringRef subSysVer;
 232     // Iterate over --{major,minor}-subsystem-version and --subsystem, and pick
 233     // the version number components from the last one of them that specifies
 234     // a version.
 235     for (auto *a : args.filtered(OPT_major_subsystem_version,
 236                                  OPT_minor_subsystem_version, OPT_subs)) {
 237       switch (a->getOption().getID()) {
 238       case OPT_major_subsystem_version:
 239         majSubSysVer = a->getValue();
 240         break;
 241       case OPT_minor_subsystem_version:
 242         minSubSysVer = a->getValue();
 243         break;
 244       case OPT_subs:
 245         std::tie(subSysName, subSysVer) = StringRef(a->getValue()).split(':');
 246         if (!subSysVer.empty()) {
 247           if (subSysVer.contains('.'))
 248             std::tie(majSubSysVer, minSubSysVer) = subSysVer.split('.');
 249           else
 250             majSubSysVer = subSysVer;
 251         }
 252         break;
 253       }
 254     }
 255     add("-osversion:" + majOSVer + "." + minOSVer);
 256     add("-subsystem:" + subSysName + "," + majSubSysVer + "." + minSubSysVer);
 257   } else if (args.hasArg(OPT_subs)) {
 258     StringRef subSys = args.getLastArgValue(OPT_subs, "default");
 259     StringRef subSysName, subSysVer;
 260     std::tie(subSysName, subSysVer) = subSys.split(':');
 261     StringRef sep = subSysVer.empty() ? "" : ",";
 262     add("-subsystem:" + subSysName + sep + subSysVer);
 263   }
 264
 265   if (auto *a = args.getLastArg(OPT_out_implib))
 266     add("-implib:" + StringRef(a->getValue()));
 267   if (auto *a = args.getLastArg(OPT_stack))
 268     add("-stack:" + StringRef(a->getValue()));
 269   if (auto *a = args.getLastArg(OPT_output_def))
 270     add("-output-def:" + StringRef(a->getValue()));
 271   if (auto *a = args.getLastArg(OPT_image_base))
 272     add("-base:" + StringRef(a->getValue()));
 273   if (auto *a = args.getLastArg(OPT_map))
 274     add("-lldmap:" + StringRef(a->getValue()));
 275   if (auto *a = args.getLastArg(OPT_reproduce))
 276     add("-reproduce:" + StringRef(a->getValue()));
 277   if (auto *a = args.getLastArg(OPT_thinlto_cache_dir))
 278     add("-lldltocache:" + StringRef(a->getValue()));
 279   if (auto *a = args.getLastArg(OPT_file_alignment))
 280     add("-filealign:" + StringRef(a->getValue()));
 281   if (auto *a = args.getLastArg(OPT_section_alignment))
 282     add("-align:" + StringRef(a->getValue()));
 283   if (auto *a = args.getLastArg(OPT_heap))
 284     add("-heap:" + StringRef(a->getValue()));
 285
 286   if (auto *a = args.getLastArg(OPT_o))
 287     add("-out:" + StringRef(a->getValue()));
 288   else if (args.hasArg(OPT_shared))
 289     add("-out:a.dll");
 290   else
 291     add("-out:a.exe");
 292
 293   if (auto *a = args.getLastArg(OPT_pdb)) {
 294     add("-debug");
 295     StringRef v = a->getValue();
 296     if (!v.empty())
 297       add("-pdb:" + v);
 298   } else if (args.hasArg(OPT_strip_debug)) {
 299     add("-debug:symtab");
 300   } else if (!args.hasArg(OPT_strip_all)) {
 301     add("-debug:dwarf");
 302   }
 303
 304   if (args.hasFlag(OPT_fatal_warnings, OPT_no_fatal_warnings, false))
 305     add("-WX");
 306   else
 307     add("-WX:no");
 308
 309   if (args.hasFlag(OPT_enable_stdcall_fixup, OPT_disable_stdcall_fixup, false))
 310     add("-stdcall-fixup");
 311   else if (args.hasArg(OPT_disable_stdcall_fixup))
 312     add("-stdcall-fixup:no");
 313
 314   if (args.hasArg(OPT_shared))
 315     add("-dll");
 316   if (args.hasArg(OPT_verbose))
 317     add("-verbose");
 318   if (args.hasArg(OPT_exclude_all_symbols))
 319     add("-exclude-all-symbols");
 320   if (args.hasArg(OPT_export_all_symbols))
 321     add("-export-all-symbols");
 322   if (args.hasArg(OPT_large_address_aware))
 323     add("-largeaddressaware");
 324   if (args.hasArg(OPT_kill_at))
 325     add("-kill-at");
 326   if (args.hasArg(OPT_appcontainer))
 327     add("-appcontainer");
 328   if (args.hasFlag(OPT_no_seh, OPT_disable_no_seh, false))
 329     add("-noseh");
 330
 331   if (args.getLastArgValue(OPT_m) != "thumb2pe" &&
 332       args.getLastArgValue(OPT_m) != "arm64pe" &&
 333       args.hasFlag(OPT_disable_dynamicbase, OPT_dynamicbase, false))
 334     add("-dynamicbase:no");
 335   if (args.hasFlag(OPT_disable_high_entropy_va, OPT_high_entropy_va, false))
 336     add("-highentropyva:no");
 337   if (args.hasFlag(OPT_disable_nxcompat, OPT_nxcompat, false))
 338     add("-nxcompat:no");
 339   if (args.hasFlag(OPT_disable_tsaware, OPT_tsaware, false))
 340     add("-tsaware:no");
 341
 342   if (args.hasFlag(OPT_disable_reloc_section, OPT_enable_reloc_section, false))
 343     add("-fixed");
 344
 345   if (args.hasFlag(OPT_no_insert_timestamp, OPT_insert_timestamp, false))
 346     add("-timestamp:0");
 347
 348   if (args.hasFlag(OPT_gc_sections, OPT_no_gc_sections, false))
 349     add("-opt:ref");
 350   else
 351     add("-opt:noref");
 352
 353   if (args.hasFlag(OPT_demangle, OPT_no_demangle, true))
 354     add("-demangle");
 355   else
 356     add("-demangle:no");
 357
 358   if (args.hasFlag(OPT_enable_auto_import, OPT_disable_auto_import, true))
 359     add("-auto-import");
 360   else
 361     add("-auto-import:no");
 362   if (args.hasFlag(OPT_enable_runtime_pseudo_reloc,
 363                    OPT_disable_runtime_pseudo_reloc, true))
 364     add("-runtime-pseudo-reloc");
 365   else
 366     add("-runtime-pseudo-reloc:no");
 367
 368   if (args.hasFlag(OPT_allow_multiple_definition,
 369                    OPT_no_allow_multiple_definition, false))
 370     add("-force:multiple");
 371
 372   if (auto *a = args.getLastArg(OPT_icf)) {
 373     StringRef s = a->getValue();
 374     if (s == "all")
 375       add("-opt:icf");
 376     else if (s == "safe" || s == "none")
 377       add("-opt:noicf");
 378     else
 379       error("unknown parameter: --icf=" + s);
 380   } else {
 381     add("-opt:noicf");
 382   }
 383
 384   if (auto *a = args.getLastArg(OPT_m)) {
 385     StringRef s = a->getValue();
 386     if (s == "i386pe")
 387       add("-machine:x86");
 388     else if (s == "i386pep")
 389       add("-machine:x64");
 390     else if (s == "thumb2pe")
 391       add("-machine:arm");
 392     else if (s == "arm64pe")
 393       add("-machine:arm64");
 394     else
 395       error("unknown parameter: -m" + s);
 396   }
 397
 398   if (args.hasFlag(OPT_guard_cf, OPT_no_guard_cf, false)) {
 399     if (args.hasFlag(OPT_guard_longjmp, OPT_no_guard_longjmp, true))
 400       add("-guard:cf,longjmp");
 401     else
 402       add("-guard:cf,nolongjmp");
 403   } else if (args.hasFlag(OPT_guard_longjmp, OPT_no_guard_longjmp, false)) {
 404     auto *a = args.getLastArg(OPT_guard_longjmp);
 405     warn("parameter " + a->getSpelling() +
 406          " only takes effect when used with --guard-cf");
 407   }
 408
 409   if (auto *a = args.getLastArg(OPT_error_limit)) {
 410     int n;
 411     StringRef s = a->getValue();
 412     if (s.getAsInteger(10, n))
 413       error(a->getSpelling() + ": number expected, but got " + s);
 414     else
 415       add("-errorlimit:" + s);
 416   }
 417
 418   for (auto *a : args.filtered(OPT_mllvm))
 419     add("-mllvm:" + StringRef(a->getValue()));
 420
 421   if (auto *arg = args.getLastArg(OPT_plugin_opt_mcpu_eq))
 422     add("-mllvm:-mcpu=" + StringRef(arg->getValue()));
 423
 424   for (auto *a : args.filtered(OPT_plugin_opt_eq_minus))
 425     add("-mllvm:-" + StringRef(a->getValue()));
 426
 427   // GCC collect2 passes -plugin-opt=path/to/lto-wrapper with an absolute or
 428   // relative path. Just ignore. If not ended with "lto-wrapper" (or
 429   // "lto-wrapper.exe" for GCC cross-compiled for Windows), consider it an
 430   // unsupported LLVMgold.so option and error.
 431   for (opt::Arg *arg : args.filtered(OPT_plugin_opt_eq)) {
 432     StringRef v(arg->getValue());
 433     if (!v.ends_with("lto-wrapper") && !v.ends_with("lto-wrapper.exe"))
 434       error(arg->getSpelling() + ": unknown plugin option '" + arg->getValue() +
 435             "'");
 436   }
 437
 438   for (auto *a : args.filtered(OPT_Xlink))
 439     add(a->getValue());
 440
 441   if (args.getLastArgValue(OPT_m) == "i386pe")
 442     add("-alternatename:__image_base__=___ImageBase");
 443   else
 444     add("-alternatename:__image_base__=__ImageBase");
 445
 446   for (auto *a : args.filtered(OPT_require_defined))
 447     add("-include:" + StringRef(a->getValue()));
 448   for (auto *a : args.filtered(OPT_undefined))
 449     add("-includeoptional:" + StringRef(a->getValue()));
 450   for (auto *a : args.filtered(OPT_delayload))
 451     add("-delayload:" + StringRef(a->getValue()));
 452   for (auto *a : args.filtered(OPT_wrap))
 453     add("-wrap:" + StringRef(a->getValue()));
 454   for (auto *a : args.filtered(OPT_exclude_symbols))
 455     add("-exclude-symbols:" + StringRef(a->getValue()));
 456
 457   std::vector<StringRef> searchPaths;
 458   for (auto *a : args.filtered(OPT_L)) {
 459     searchPaths.push_back(a->getValue());
 460     add("-libpath:" + StringRef(a->getValue()));
 461   }
 462
 463   StringRef prefix = "";
 464   bool isStatic = false;
 465   for (auto *a : args) {
 466     switch (a->getOption().getID()) {
 467     case OPT_INPUT:
 468       if (StringRef(a->getValue()).ends_with_insensitive(".def"))
 469         add("-def:" + StringRef(a->getValue()));
 470       else
 471         add(prefix + StringRef(a->getValue()));
 472       break;
 473     case OPT_l:
 474       add(prefix + searchLibrary(a->getValue(), searchPaths, isStatic));
 475       break;
 476     case OPT_whole_archive:
 477       prefix = "-wholearchive:";
 478       break;
 479     case OPT_no_whole_archive:
 480       prefix = "";
 481       break;
 482     case OPT_Bstatic:
 483       isStatic = true;
 484       break;
 485     case OPT_Bdynamic:
 486       isStatic = false;
 487       break;
 488     }
 489   }
 490
 491   if (errorCount())
 492     return false;
 493
 494   if (args.hasArg(OPT_verbose) || args.hasArg(OPT__HASH_HASH_HASH))
 495     lld::errs() << llvm::join(linkArgs, " ") << "\n";
 496
 497   if (args.hasArg(OPT__HASH_HASH_HASH))
 498     return true;
 499
 500   // Repack vector of strings to vector of const char pointers for coff::link.
 501   std::vector<const char *> vec;
 502   for (const std::string &s : linkArgs)
 503     vec.push_back(s.c_str());
 504   // Pass the actual binary name, to make error messages be printed with
 505   // the right prefix.
 506   vec[0] = argsArr[0];
 507
 508   // The context will be re-created in the COFF driver.
 509   lld::CommonLinkerContext::destroy();
 510
 511   return coff::link(vec, stdoutOS, stderrOS, exitEarly, disableOutput);
 512 }
 513 } // namespace mingw
 514 } // namespace lld