xref: /llvm-project-15.0.7/lld/MinGW/Driver.cpp (revision 0eaee545)
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/ErrorHandler.h"
33 #include "lld/Common/Memory.h"
34 #include "lld/Common/Version.h"
35 #include "llvm/ADT/ArrayRef.h"
36 #include "llvm/ADT/Optional.h"
37 #include "llvm/ADT/StringExtras.h"
38 #include "llvm/ADT/StringRef.h"
39 #include "llvm/ADT/Triple.h"
40 #include "llvm/Option/Arg.h"
41 #include "llvm/Option/ArgList.h"
42 #include "llvm/Option/Option.h"
43 #include "llvm/Support/CommandLine.h"
44 #include "llvm/Support/FileSystem.h"
45 #include "llvm/Support/Path.h"
46 
47 #if !defined(_MSC_VER) && !defined(__MINGW32__)
48 #include <unistd.h>
49 #endif
50 
51 using namespace lld;
52 using namespace llvm;
53 
54 // Create OptTable
55 enum {
56   OPT_INVALID = 0,
57 #define OPTION(_1, _2, ID, _4, _5, _6, _7, _8, _9, _10, _11, _12) OPT_##ID,
58 #include "Options.inc"
59 #undef OPTION
60 };
61 
62 // Create prefix string literals used in Options.td
63 #define PREFIX(NAME, VALUE) static const char *const NAME[] = VALUE;
64 #include "Options.inc"
65 #undef PREFIX
66 
67 // Create table mapping all options defined in Options.td
68 static const opt::OptTable::Info infoTable[] = {
69 #define OPTION(X1, X2, ID, KIND, GROUP, ALIAS, X7, X8, X9, X10, X11, X12)      \
70   {X1, X2, X10,         X11,         OPT_##ID, opt::Option::KIND##Class,       \
71    X9, X8, OPT_##GROUP, OPT_##ALIAS, X7,       X12},
72 #include "Options.inc"
73 #undef OPTION
74 };
75 
76 namespace {
77 class MinGWOptTable : public opt::OptTable {
78 public:
79   MinGWOptTable() : OptTable(infoTable, false) {}
80   opt::InputArgList parse(ArrayRef<const char *> argv);
81 };
82 } // namespace
83 
84 static void printHelp(const char *argv0) {
85   MinGWOptTable().PrintHelp(
86       outs(), (std::string(argv0) + " [options] file...").c_str(), "lld",
87       false /*ShowHidden*/, true /*ShowAllAliases*/);
88   outs() << "\n";
89 }
90 
91 static cl::TokenizerCallback getQuotingStyle() {
92   if (Triple(sys::getProcessTriple()).getOS() == Triple::Win32)
93     return cl::TokenizeWindowsCommandLine;
94   return cl::TokenizeGNUCommandLine;
95 }
96 
97 opt::InputArgList MinGWOptTable::parse(ArrayRef<const char *> argv) {
98   unsigned missingIndex;
99   unsigned missingCount;
100 
101   SmallVector<const char *, 256> vec(argv.data(), argv.data() + argv.size());
102   cl::ExpandResponseFiles(saver, getQuotingStyle(), vec);
103   opt::InputArgList args = this->ParseArgs(vec, missingIndex, missingCount);
104 
105   if (missingCount)
106     fatal(StringRef(args.getArgString(missingIndex)) + ": missing argument");
107   for (auto *arg : args.filtered(OPT_UNKNOWN))
108     fatal("unknown argument: " + arg->getAsString(args));
109   return args;
110 }
111 
112 // Find a file by concatenating given paths.
113 static Optional<std::string> findFile(StringRef path1, const Twine &path2) {
114   SmallString<128> s;
115   sys::path::append(s, path1, path2);
116   if (sys::fs::exists(s))
117     return s.str().str();
118   return None;
119 }
120 
121 // This is for -lfoo. We'll look for libfoo.dll.a or libfoo.a from search paths.
122 static std::string
123 searchLibrary(StringRef name, ArrayRef<StringRef> searchPaths, bool bStatic) {
124   if (name.startswith(":")) {
125     for (StringRef dir : searchPaths)
126       if (Optional<std::string> s = findFile(dir, name.substr(1)))
127         return *s;
128     fatal("unable to find library -l" + name);
129   }
130 
131   for (StringRef dir : searchPaths) {
132     if (!bStatic)
133       if (Optional<std::string> s = findFile(dir, "lib" + name + ".dll.a"))
134         return *s;
135     if (Optional<std::string> s = findFile(dir, "lib" + name + ".a"))
136       return *s;
137   }
138   fatal("unable to find library -l" + name);
139 }
140 
141 // Convert Unix-ish command line arguments to Windows-ish ones and
142 // then call coff::link.
143 bool mingw::link(ArrayRef<const char *> argsArr, raw_ostream &diag) {
144   MinGWOptTable parser;
145   opt::InputArgList args = parser.parse(argsArr.slice(1));
146 
147   if (args.hasArg(OPT_help)) {
148     printHelp(argsArr[0]);
149     return true;
150   }
151 
152   // A note about "compatible with GNU linkers" message: this is a hack for
153   // scripts generated by GNU Libtool 2.4.6 (released in February 2014 and
154   // still the newest version in March 2017) or earlier to recognize LLD as
155   // a GNU compatible linker. As long as an output for the -v option
156   // contains "GNU" or "with BFD", they recognize us as GNU-compatible.
157   if (args.hasArg(OPT_v) || args.hasArg(OPT_version))
158     message(getLLDVersion() + " (compatible with GNU linkers)");
159 
160   // The behavior of -v or --version is a bit strange, but this is
161   // needed for compatibility with GNU linkers.
162   if (args.hasArg(OPT_v) && !args.hasArg(OPT_INPUT) && !args.hasArg(OPT_l))
163     return true;
164   if (args.hasArg(OPT_version))
165     return true;
166 
167   if (!args.hasArg(OPT_INPUT) && !args.hasArg(OPT_l))
168     fatal("no input files");
169 
170   std::vector<std::string> linkArgs;
171   auto add = [&](const Twine &s) { linkArgs.push_back(s.str()); };
172 
173   add("lld-link");
174   add("-lldmingw");
175 
176   if (auto *a = args.getLastArg(OPT_entry)) {
177     StringRef s = a->getValue();
178     if (args.getLastArgValue(OPT_m) == "i386pe" && s.startswith("_"))
179       add("-entry:" + s.substr(1));
180     else
181       add("-entry:" + s);
182   }
183 
184   if (args.hasArg(OPT_major_os_version, OPT_minor_os_version,
185                   OPT_major_subsystem_version, OPT_minor_subsystem_version)) {
186     auto *majOSVer = args.getLastArg(OPT_major_os_version);
187     auto *minOSVer = args.getLastArg(OPT_minor_os_version);
188     auto *majSubSysVer = args.getLastArg(OPT_major_subsystem_version);
189     auto *minSubSysVer = args.getLastArg(OPT_minor_subsystem_version);
190     if (majOSVer && majSubSysVer &&
191         StringRef(majOSVer->getValue()) != StringRef(majSubSysVer->getValue()))
192       warn("--major-os-version and --major-subsystem-version set to differing "
193            "versions, not supported");
194     if (minOSVer && minSubSysVer &&
195         StringRef(minOSVer->getValue()) != StringRef(minSubSysVer->getValue()))
196       warn("--minor-os-version and --minor-subsystem-version set to differing "
197            "versions, not supported");
198     StringRef subSys = args.getLastArgValue(OPT_subs, "default");
199     StringRef major = majOSVer ? majOSVer->getValue()
200                                : majSubSysVer ? majSubSysVer->getValue() : "6";
201     StringRef minor = minOSVer ? minOSVer->getValue()
202                                : minSubSysVer ? minSubSysVer->getValue() : "";
203     StringRef sep = minor.empty() ? "" : ".";
204     add("-subsystem:" + subSys + "," + major + sep + minor);
205   } else if (auto *a = args.getLastArg(OPT_subs)) {
206     add("-subsystem:" + StringRef(a->getValue()));
207   }
208 
209   if (auto *a = args.getLastArg(OPT_out_implib))
210     add("-implib:" + StringRef(a->getValue()));
211   if (auto *a = args.getLastArg(OPT_stack))
212     add("-stack:" + StringRef(a->getValue()));
213   if (auto *a = args.getLastArg(OPT_output_def))
214     add("-output-def:" + StringRef(a->getValue()));
215   if (auto *a = args.getLastArg(OPT_image_base))
216     add("-base:" + StringRef(a->getValue()));
217   if (auto *a = args.getLastArg(OPT_map))
218     add("-lldmap:" + StringRef(a->getValue()));
219 
220   if (auto *a = args.getLastArg(OPT_o))
221     add("-out:" + StringRef(a->getValue()));
222   else if (args.hasArg(OPT_shared))
223     add("-out:a.dll");
224   else
225     add("-out:a.exe");
226 
227   if (auto *a = args.getLastArg(OPT_pdb)) {
228     add("-debug");
229     StringRef v = a->getValue();
230     if (!v.empty())
231       add("-pdb:" + v);
232   } else if (args.hasArg(OPT_strip_debug)) {
233     add("-debug:symtab");
234   } else if (!args.hasArg(OPT_strip_all)) {
235     add("-debug:dwarf");
236   }
237 
238   if (args.hasArg(OPT_shared))
239     add("-dll");
240   if (args.hasArg(OPT_verbose))
241     add("-verbose");
242   if (args.hasArg(OPT_exclude_all_symbols))
243     add("-exclude-all-symbols");
244   if (args.hasArg(OPT_export_all_symbols))
245     add("-export-all-symbols");
246   if (args.hasArg(OPT_large_address_aware))
247     add("-largeaddressaware");
248   if (args.hasArg(OPT_kill_at))
249     add("-kill-at");
250   if (args.hasArg(OPT_appcontainer))
251     add("-appcontainer");
252 
253   if (args.getLastArgValue(OPT_m) != "thumb2pe" &&
254       args.getLastArgValue(OPT_m) != "arm64pe" && !args.hasArg(OPT_dynamicbase))
255     add("-dynamicbase:no");
256 
257   if (args.hasFlag(OPT_no_insert_timestamp, OPT_insert_timestamp, false))
258     add("-timestamp:0");
259 
260   if (args.hasFlag(OPT_gc_sections, OPT_no_gc_sections, false))
261     add("-opt:ref");
262   else
263     add("-opt:noref");
264 
265   if (auto *a = args.getLastArg(OPT_icf)) {
266     StringRef s = a->getValue();
267     if (s == "all")
268       add("-opt:icf");
269     else if (s == "safe" || s == "none")
270       add("-opt:noicf");
271     else
272       fatal("unknown parameter: --icf=" + s);
273   } else {
274     add("-opt:noicf");
275   }
276 
277   if (auto *a = args.getLastArg(OPT_m)) {
278     StringRef s = a->getValue();
279     if (s == "i386pe")
280       add("-machine:x86");
281     else if (s == "i386pep")
282       add("-machine:x64");
283     else if (s == "thumb2pe")
284       add("-machine:arm");
285     else if (s == "arm64pe")
286       add("-machine:arm64");
287     else
288       fatal("unknown parameter: -m" + s);
289   }
290 
291   for (auto *a : args.filtered(OPT_mllvm))
292     add("-mllvm:" + StringRef(a->getValue()));
293 
294   for (auto *a : args.filtered(OPT_Xlink))
295     add(a->getValue());
296 
297   if (args.getLastArgValue(OPT_m) == "i386pe")
298     add("-alternatename:__image_base__=___ImageBase");
299   else
300     add("-alternatename:__image_base__=__ImageBase");
301 
302   for (auto *a : args.filtered(OPT_require_defined))
303     add("-include:" + StringRef(a->getValue()));
304   for (auto *a : args.filtered(OPT_undefined))
305     add("-includeoptional:" + StringRef(a->getValue()));
306   for (auto *a : args.filtered(OPT_delayload))
307     add("-delayload:" + StringRef(a->getValue()));
308 
309   std::vector<StringRef> searchPaths;
310   for (auto *a : args.filtered(OPT_L)) {
311     searchPaths.push_back(a->getValue());
312     add("-libpath:" + StringRef(a->getValue()));
313   }
314 
315   StringRef prefix = "";
316   bool isStatic = false;
317   for (auto *a : args) {
318     switch (a->getOption().getID()) {
319     case OPT_INPUT:
320       if (StringRef(a->getValue()).endswith_lower(".def"))
321         add("-def:" + StringRef(a->getValue()));
322       else
323         add(prefix + StringRef(a->getValue()));
324       break;
325     case OPT_l:
326       add(prefix + searchLibrary(a->getValue(), searchPaths, isStatic));
327       break;
328     case OPT_whole_archive:
329       prefix = "-wholearchive:";
330       break;
331     case OPT_no_whole_archive:
332       prefix = "";
333       break;
334     case OPT_Bstatic:
335       isStatic = true;
336       break;
337     case OPT_Bdynamic:
338       isStatic = false;
339       break;
340     }
341   }
342 
343   if (args.hasArg(OPT_verbose) || args.hasArg(OPT__HASH_HASH_HASH))
344     outs() << llvm::join(linkArgs, " ") << "\n";
345 
346   if (args.hasArg(OPT__HASH_HASH_HASH))
347     return true;
348 
349   // Repack vector of strings to vector of const char pointers for coff::link.
350   std::vector<const char *> vec;
351   for (const std::string &s : linkArgs)
352     vec.push_back(s.c_str());
353   return coff::link(vec, true);
354 }
355