1 //===--- CompilerInvocation.cpp -------------------------------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "clang/Frontend/CompilerInvocation.h"
11 #include "clang/Basic/FileManager.h"
12 #include "clang/Basic/Version.h"
13 #include "clang/Driver/DriverDiagnostic.h"
14 #include "clang/Driver/Options.h"
15 #include "clang/Driver/Util.h"
16 #include "clang/Frontend/FrontendDiagnostic.h"
17 #include "clang/Frontend/LangStandard.h"
18 #include "clang/Frontend/Utils.h"
19 #include "clang/Lex/HeaderSearchOptions.h"
20 #include "clang/Serialization/ASTReader.h"
21 #include "llvm/ADT/Hashing.h"
22 #include "llvm/ADT/SmallVector.h"
23 #include "llvm/ADT/StringExtras.h"
24 #include "llvm/ADT/StringSwitch.h"
25 #include "llvm/ADT/Triple.h"
26 #include "llvm/Option/Arg.h"
27 #include "llvm/Option/ArgList.h"
28 #include "llvm/Option/OptTable.h"
29 #include "llvm/Option/Option.h"
30 #include "llvm/Support/ErrorHandling.h"
31 #include "llvm/Support/FileSystem.h"
32 #include "llvm/Support/Host.h"
33 #include "llvm/Support/Path.h"
34 #include "llvm/Support/Process.h"
35 #include "llvm/Support/system_error.h"
36 #include <atomic>
37 #include <memory>
38 #include <sys/stat.h>
39 using namespace clang;
40 
41 //===----------------------------------------------------------------------===//
42 // Initialization.
43 //===----------------------------------------------------------------------===//
44 
45 CompilerInvocationBase::CompilerInvocationBase()
46   : LangOpts(new LangOptions()), TargetOpts(new TargetOptions()),
47     DiagnosticOpts(new DiagnosticOptions()),
48     HeaderSearchOpts(new HeaderSearchOptions()),
49     PreprocessorOpts(new PreprocessorOptions()) {}
50 
51 CompilerInvocationBase::CompilerInvocationBase(const CompilerInvocationBase &X)
52   : RefCountedBase<CompilerInvocation>(),
53     LangOpts(new LangOptions(*X.getLangOpts())),
54     TargetOpts(new TargetOptions(X.getTargetOpts())),
55     DiagnosticOpts(new DiagnosticOptions(X.getDiagnosticOpts())),
56     HeaderSearchOpts(new HeaderSearchOptions(X.getHeaderSearchOpts())),
57     PreprocessorOpts(new PreprocessorOptions(X.getPreprocessorOpts())) {}
58 
59 //===----------------------------------------------------------------------===//
60 // Deserialization (from args)
61 //===----------------------------------------------------------------------===//
62 
63 using namespace clang::driver;
64 using namespace clang::driver::options;
65 using namespace llvm::opt;
66 
67 //
68 
69 static unsigned getOptimizationLevel(ArgList &Args, InputKind IK,
70                                      DiagnosticsEngine &Diags) {
71   unsigned DefaultOpt = 0;
72   if (IK == IK_OpenCL && !Args.hasArg(OPT_cl_opt_disable))
73     DefaultOpt = 2;
74 
75   if (Arg *A = Args.getLastArg(options::OPT_O_Group)) {
76     if (A->getOption().matches(options::OPT_O0))
77       return 0;
78 
79     if (A->getOption().matches(options::OPT_Ofast))
80       return 3;
81 
82     assert (A->getOption().matches(options::OPT_O));
83 
84     StringRef S(A->getValue());
85     if (S == "s" || S == "z" || S.empty())
86       return 2;
87 
88     return getLastArgIntValue(Args, OPT_O, DefaultOpt, Diags);
89   }
90 
91   return DefaultOpt;
92 }
93 
94 static unsigned getOptimizationLevelSize(ArgList &Args) {
95   if (Arg *A = Args.getLastArg(options::OPT_O_Group)) {
96     if (A->getOption().matches(options::OPT_O)) {
97       switch (A->getValue()[0]) {
98       default:
99         return 0;
100       case 's':
101         return 1;
102       case 'z':
103         return 2;
104       }
105     }
106   }
107   return 0;
108 }
109 
110 static void addWarningArgs(ArgList &Args, std::vector<std::string> &Warnings) {
111   for (arg_iterator I = Args.filtered_begin(OPT_W_Group),
112          E = Args.filtered_end(); I != E; ++I) {
113     Arg *A = *I;
114     // If the argument is a pure flag, add its name (minus the "W" at the beginning)
115     // to the warning list. Else, add its value (for the OPT_W case).
116     if (A->getOption().getKind() == Option::FlagClass) {
117       Warnings.push_back(A->getOption().getName().substr(1));
118     } else {
119       for (unsigned Idx = 0, End = A->getNumValues();
120            Idx < End; ++Idx) {
121         StringRef V = A->getValue(Idx);
122         // "-Wl," and such are not warning options.
123         // FIXME: Should be handled by putting these in separate flags.
124         if (V.startswith("l,") || V.startswith("a,") || V.startswith("p,"))
125           continue;
126 
127         Warnings.push_back(V);
128       }
129     }
130   }
131 }
132 
133 static bool ParseAnalyzerArgs(AnalyzerOptions &Opts, ArgList &Args,
134                               DiagnosticsEngine &Diags) {
135   using namespace options;
136   bool Success = true;
137   if (Arg *A = Args.getLastArg(OPT_analyzer_store)) {
138     StringRef Name = A->getValue();
139     AnalysisStores Value = llvm::StringSwitch<AnalysisStores>(Name)
140 #define ANALYSIS_STORE(NAME, CMDFLAG, DESC, CREATFN) \
141       .Case(CMDFLAG, NAME##Model)
142 #include "clang/StaticAnalyzer/Core/Analyses.def"
143       .Default(NumStores);
144     if (Value == NumStores) {
145       Diags.Report(diag::err_drv_invalid_value)
146         << A->getAsString(Args) << Name;
147       Success = false;
148     } else {
149       Opts.AnalysisStoreOpt = Value;
150     }
151   }
152 
153   if (Arg *A = Args.getLastArg(OPT_analyzer_constraints)) {
154     StringRef Name = A->getValue();
155     AnalysisConstraints Value = llvm::StringSwitch<AnalysisConstraints>(Name)
156 #define ANALYSIS_CONSTRAINTS(NAME, CMDFLAG, DESC, CREATFN) \
157       .Case(CMDFLAG, NAME##Model)
158 #include "clang/StaticAnalyzer/Core/Analyses.def"
159       .Default(NumConstraints);
160     if (Value == NumConstraints) {
161       Diags.Report(diag::err_drv_invalid_value)
162         << A->getAsString(Args) << Name;
163       Success = false;
164     } else {
165       Opts.AnalysisConstraintsOpt = Value;
166     }
167   }
168 
169   if (Arg *A = Args.getLastArg(OPT_analyzer_output)) {
170     StringRef Name = A->getValue();
171     AnalysisDiagClients Value = llvm::StringSwitch<AnalysisDiagClients>(Name)
172 #define ANALYSIS_DIAGNOSTICS(NAME, CMDFLAG, DESC, CREATFN) \
173       .Case(CMDFLAG, PD_##NAME)
174 #include "clang/StaticAnalyzer/Core/Analyses.def"
175       .Default(NUM_ANALYSIS_DIAG_CLIENTS);
176     if (Value == NUM_ANALYSIS_DIAG_CLIENTS) {
177       Diags.Report(diag::err_drv_invalid_value)
178         << A->getAsString(Args) << Name;
179       Success = false;
180     } else {
181       Opts.AnalysisDiagOpt = Value;
182     }
183   }
184 
185   if (Arg *A = Args.getLastArg(OPT_analyzer_purge)) {
186     StringRef Name = A->getValue();
187     AnalysisPurgeMode Value = llvm::StringSwitch<AnalysisPurgeMode>(Name)
188 #define ANALYSIS_PURGE(NAME, CMDFLAG, DESC) \
189       .Case(CMDFLAG, NAME)
190 #include "clang/StaticAnalyzer/Core/Analyses.def"
191       .Default(NumPurgeModes);
192     if (Value == NumPurgeModes) {
193       Diags.Report(diag::err_drv_invalid_value)
194         << A->getAsString(Args) << Name;
195       Success = false;
196     } else {
197       Opts.AnalysisPurgeOpt = Value;
198     }
199   }
200 
201   if (Arg *A = Args.getLastArg(OPT_analyzer_inlining_mode)) {
202     StringRef Name = A->getValue();
203     AnalysisInliningMode Value = llvm::StringSwitch<AnalysisInliningMode>(Name)
204 #define ANALYSIS_INLINING_MODE(NAME, CMDFLAG, DESC) \
205       .Case(CMDFLAG, NAME)
206 #include "clang/StaticAnalyzer/Core/Analyses.def"
207       .Default(NumInliningModes);
208     if (Value == NumInliningModes) {
209       Diags.Report(diag::err_drv_invalid_value)
210         << A->getAsString(Args) << Name;
211       Success = false;
212     } else {
213       Opts.InliningMode = Value;
214     }
215   }
216 
217   Opts.ShowCheckerHelp = Args.hasArg(OPT_analyzer_checker_help);
218   Opts.visualizeExplodedGraphWithGraphViz =
219     Args.hasArg(OPT_analyzer_viz_egraph_graphviz);
220   Opts.visualizeExplodedGraphWithUbiGraph =
221     Args.hasArg(OPT_analyzer_viz_egraph_ubigraph);
222   Opts.NoRetryExhausted = Args.hasArg(OPT_analyzer_disable_retry_exhausted);
223   Opts.AnalyzeAll = Args.hasArg(OPT_analyzer_opt_analyze_headers);
224   Opts.AnalyzerDisplayProgress = Args.hasArg(OPT_analyzer_display_progress);
225   Opts.AnalyzeNestedBlocks =
226     Args.hasArg(OPT_analyzer_opt_analyze_nested_blocks);
227   Opts.eagerlyAssumeBinOpBifurcation = Args.hasArg(OPT_analyzer_eagerly_assume);
228   Opts.AnalyzeSpecificFunction = Args.getLastArgValue(OPT_analyze_function);
229   Opts.UnoptimizedCFG = Args.hasArg(OPT_analysis_UnoptimizedCFG);
230   Opts.TrimGraph = Args.hasArg(OPT_trim_egraph);
231   Opts.maxBlockVisitOnPath =
232       getLastArgIntValue(Args, OPT_analyzer_max_loop, 4, Diags);
233   Opts.PrintStats = Args.hasArg(OPT_analyzer_stats);
234   Opts.InlineMaxStackDepth =
235       getLastArgIntValue(Args, OPT_analyzer_inline_max_stack_depth,
236                          Opts.InlineMaxStackDepth, Diags);
237 
238   Opts.CheckersControlList.clear();
239   for (arg_iterator it = Args.filtered_begin(OPT_analyzer_checker,
240                                              OPT_analyzer_disable_checker),
241          ie = Args.filtered_end(); it != ie; ++it) {
242     const Arg *A = *it;
243     A->claim();
244     bool enable = (A->getOption().getID() == OPT_analyzer_checker);
245     // We can have a list of comma separated checker names, e.g:
246     // '-analyzer-checker=cocoa,unix'
247     StringRef checkerList = A->getValue();
248     SmallVector<StringRef, 4> checkers;
249     checkerList.split(checkers, ",");
250     for (unsigned i = 0, e = checkers.size(); i != e; ++i)
251       Opts.CheckersControlList.push_back(std::make_pair(checkers[i], enable));
252   }
253 
254   // Go through the analyzer configuration options.
255   for (arg_iterator it = Args.filtered_begin(OPT_analyzer_config),
256        ie = Args.filtered_end(); it != ie; ++it) {
257     const Arg *A = *it;
258     A->claim();
259     // We can have a list of comma separated config names, e.g:
260     // '-analyzer-config key1=val1,key2=val2'
261     StringRef configList = A->getValue();
262     SmallVector<StringRef, 4> configVals;
263     configList.split(configVals, ",");
264     for (unsigned i = 0, e = configVals.size(); i != e; ++i) {
265       StringRef key, val;
266       std::tie(key, val) = configVals[i].split("=");
267       if (val.empty()) {
268         Diags.Report(SourceLocation(),
269                      diag::err_analyzer_config_no_value) << configVals[i];
270         Success = false;
271         break;
272       }
273       if (val.find('=') != StringRef::npos) {
274         Diags.Report(SourceLocation(),
275                      diag::err_analyzer_config_multiple_values)
276           << configVals[i];
277         Success = false;
278         break;
279       }
280       Opts.Config[key] = val;
281     }
282   }
283 
284   return Success;
285 }
286 
287 static bool ParseMigratorArgs(MigratorOptions &Opts, ArgList &Args) {
288   Opts.NoNSAllocReallocError = Args.hasArg(OPT_migrator_no_nsalloc_error);
289   Opts.NoFinalizeRemoval = Args.hasArg(OPT_migrator_no_finalize_removal);
290   return true;
291 }
292 
293 static void ParseCommentArgs(CommentOptions &Opts, ArgList &Args) {
294   Opts.BlockCommandNames = Args.getAllArgValues(OPT_fcomment_block_commands);
295   Opts.ParseAllComments = Args.hasArg(OPT_fparse_all_comments);
296 }
297 
298 static bool ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK,
299                              DiagnosticsEngine &Diags,
300                              const TargetOptions &TargetOpts) {
301   using namespace options;
302   bool Success = true;
303 
304   Opts.OptimizationLevel = getOptimizationLevel(Args, IK, Diags);
305   // TODO: This could be done in Driver
306   unsigned MaxOptLevel = 3;
307   if (Opts.OptimizationLevel > MaxOptLevel) {
308     // If the optimization level is not supported, fall back on the default optimization
309     Diags.Report(diag::warn_drv_optimization_value)
310         << Args.getLastArg(OPT_O)->getAsString(Args) << "-O" << MaxOptLevel;
311     Opts.OptimizationLevel = MaxOptLevel;
312   }
313 
314   // We must always run at least the always inlining pass.
315   Opts.setInlining(
316     (Opts.OptimizationLevel > 1) ? CodeGenOptions::NormalInlining
317                                  : CodeGenOptions::OnlyAlwaysInlining);
318   // -fno-inline-functions overrides OptimizationLevel > 1.
319   Opts.NoInline = Args.hasArg(OPT_fno_inline);
320   Opts.setInlining(Args.hasArg(OPT_fno_inline_functions) ?
321                      CodeGenOptions::OnlyAlwaysInlining : Opts.getInlining());
322 
323   if (Args.hasArg(OPT_gline_tables_only)) {
324     Opts.setDebugInfo(CodeGenOptions::DebugLineTablesOnly);
325   } else if (Args.hasArg(OPT_g_Flag) || Args.hasArg(OPT_gdwarf_2) ||
326              Args.hasArg(OPT_gdwarf_3) || Args.hasArg(OPT_gdwarf_4)) {
327     bool Default = false;
328     // Until dtrace (via CTF) can deal with distributed debug info,
329     // Darwin defaults to standalone/full debug info.
330     if (llvm::Triple(TargetOpts.Triple).isOSDarwin())
331       Default = true;
332 
333     if (Args.hasFlag(OPT_fstandalone_debug, OPT_fno_standalone_debug, Default))
334       Opts.setDebugInfo(CodeGenOptions::FullDebugInfo);
335     else
336       Opts.setDebugInfo(CodeGenOptions::LimitedDebugInfo);
337   }
338   Opts.DebugColumnInfo = Args.hasArg(OPT_dwarf_column_info);
339   Opts.SplitDwarfFile = Args.getLastArgValue(OPT_split_dwarf_file);
340   if (Args.hasArg(OPT_gdwarf_2))
341     Opts.DwarfVersion = 2;
342   else if (Args.hasArg(OPT_gdwarf_3))
343     Opts.DwarfVersion = 3;
344   else if (Args.hasArg(OPT_gdwarf_4))
345     Opts.DwarfVersion = 4;
346   else if (Opts.getDebugInfo() != CodeGenOptions::NoDebugInfo)
347     // Default Dwarf version is 4 if we are generating debug information.
348     Opts.DwarfVersion = 4;
349 
350   Opts.DisableLLVMOpts = Args.hasArg(OPT_disable_llvm_optzns);
351   Opts.DisableRedZone = Args.hasArg(OPT_disable_red_zone);
352   Opts.ForbidGuardVariables = Args.hasArg(OPT_fforbid_guard_variables);
353   Opts.UseRegisterSizedBitfieldAccess = Args.hasArg(
354     OPT_fuse_register_sized_bitfield_access);
355   Opts.RelaxedAliasing = Args.hasArg(OPT_relaxed_aliasing);
356   Opts.StructPathTBAA = !Args.hasArg(OPT_no_struct_path_tbaa);
357   Opts.DwarfDebugFlags = Args.getLastArgValue(OPT_dwarf_debug_flags);
358   Opts.MergeAllConstants = !Args.hasArg(OPT_fno_merge_all_constants);
359   Opts.NoCommon = Args.hasArg(OPT_fno_common);
360   Opts.NoImplicitFloat = Args.hasArg(OPT_no_implicit_float);
361   Opts.OptimizeSize = getOptimizationLevelSize(Args);
362   Opts.SimplifyLibCalls = !(Args.hasArg(OPT_fno_builtin) ||
363                             Args.hasArg(OPT_ffreestanding));
364   Opts.UnrollLoops =
365       Args.hasFlag(OPT_funroll_loops, OPT_fno_unroll_loops,
366                    (Opts.OptimizationLevel > 1 && !Opts.OptimizeSize));
367   Opts.RerollLoops = Args.hasArg(OPT_freroll_loops);
368 
369   Opts.DisableIntegratedAS = Args.hasArg(OPT_fno_integrated_as);
370   Opts.Autolink = !Args.hasArg(OPT_fno_autolink);
371   Opts.SampleProfileFile = Args.getLastArgValue(OPT_fprofile_sample_use_EQ);
372   Opts.ProfileInstrGenerate = Args.hasArg(OPT_fprofile_instr_generate);
373   Opts.InstrProfileInput = Args.getLastArgValue(OPT_fprofile_instr_use_EQ);
374   Opts.AsmVerbose = Args.hasArg(OPT_masm_verbose);
375   Opts.ObjCAutoRefCountExceptions = Args.hasArg(OPT_fobjc_arc_exceptions);
376   Opts.CUDAIsDevice = Args.hasArg(OPT_fcuda_is_device);
377   Opts.CXAAtExit = !Args.hasArg(OPT_fno_use_cxa_atexit);
378   Opts.CXXCtorDtorAliases = Args.hasArg(OPT_mconstructor_aliases);
379   Opts.CodeModel = Args.getLastArgValue(OPT_mcode_model);
380   Opts.DebugPass = Args.getLastArgValue(OPT_mdebug_pass);
381   Opts.DisableFPElim = Args.hasArg(OPT_mdisable_fp_elim);
382   Opts.DisableFree = Args.hasArg(OPT_disable_free);
383   Opts.DisableTailCalls = Args.hasArg(OPT_mdisable_tail_calls);
384   Opts.FloatABI = Args.getLastArgValue(OPT_mfloat_abi);
385   Opts.LessPreciseFPMAD = Args.hasArg(OPT_cl_mad_enable);
386   Opts.LimitFloatPrecision = Args.getLastArgValue(OPT_mlimit_float_precision);
387   Opts.NoInfsFPMath = (Args.hasArg(OPT_menable_no_infinities) ||
388                        Args.hasArg(OPT_cl_finite_math_only)||
389                        Args.hasArg(OPT_cl_fast_relaxed_math));
390   Opts.NoNaNsFPMath = (Args.hasArg(OPT_menable_no_nans) ||
391                        Args.hasArg(OPT_cl_finite_math_only)||
392                        Args.hasArg(OPT_cl_fast_relaxed_math));
393   Opts.NoZeroInitializedInBSS = Args.hasArg(OPT_mno_zero_initialized_in_bss);
394   Opts.BackendOptions = Args.getAllArgValues(OPT_backend_option);
395   Opts.NumRegisterParameters = getLastArgIntValue(Args, OPT_mregparm, 0, Diags);
396   Opts.NoGlobalMerge = Args.hasArg(OPT_mno_global_merge);
397   Opts.NoExecStack = Args.hasArg(OPT_mno_exec_stack);
398   Opts.EnableSegmentedStacks = Args.hasArg(OPT_split_stacks);
399   Opts.RelaxAll = Args.hasArg(OPT_mrelax_all);
400   Opts.OmitLeafFramePointer = Args.hasArg(OPT_momit_leaf_frame_pointer);
401   Opts.SaveTempLabels = Args.hasArg(OPT_msave_temp_labels);
402   Opts.NoDwarfDirectoryAsm = Args.hasArg(OPT_fno_dwarf_directory_asm);
403   Opts.SoftFloat = Args.hasArg(OPT_msoft_float);
404   Opts.StrictEnums = Args.hasArg(OPT_fstrict_enums);
405   Opts.UnsafeFPMath = Args.hasArg(OPT_menable_unsafe_fp_math) ||
406                       Args.hasArg(OPT_cl_unsafe_math_optimizations) ||
407                       Args.hasArg(OPT_cl_fast_relaxed_math);
408   Opts.UnwindTables = Args.hasArg(OPT_munwind_tables);
409   Opts.RelocationModel = Args.getLastArgValue(OPT_mrelocation_model, "pic");
410   Opts.TrapFuncName = Args.getLastArgValue(OPT_ftrap_function_EQ);
411   Opts.UseInitArray = Args.hasArg(OPT_fuse_init_array);
412 
413   Opts.FunctionSections = Args.hasFlag(OPT_ffunction_sections,
414                                        OPT_fno_function_sections, false);
415   Opts.DataSections = Args.hasFlag(OPT_fdata_sections,
416                                    OPT_fno_data_sections, false);
417 
418   Opts.VectorizeBB = Args.hasArg(OPT_vectorize_slp_aggressive);
419   Opts.VectorizeLoop = Args.hasArg(OPT_vectorize_loops);
420   Opts.VectorizeSLP = Args.hasArg(OPT_vectorize_slp);
421 
422   Opts.MainFileName = Args.getLastArgValue(OPT_main_file_name);
423   Opts.VerifyModule = !Args.hasArg(OPT_disable_llvm_verifier);
424   Opts.SanitizeRecover = !Args.hasArg(OPT_fno_sanitize_recover);
425 
426   Opts.DisableGCov = Args.hasArg(OPT_test_coverage);
427   Opts.EmitGcovArcs = Args.hasArg(OPT_femit_coverage_data);
428   Opts.EmitGcovNotes = Args.hasArg(OPT_femit_coverage_notes);
429   if (Opts.EmitGcovArcs || Opts.EmitGcovNotes) {
430   Opts.CoverageFile = Args.getLastArgValue(OPT_coverage_file);
431     Opts.CoverageExtraChecksum = Args.hasArg(OPT_coverage_cfg_checksum);
432     Opts.CoverageNoFunctionNamesInData =
433         Args.hasArg(OPT_coverage_no_function_names_in_data);
434     if (Args.hasArg(OPT_coverage_version_EQ)) {
435       StringRef CoverageVersion = Args.getLastArgValue(OPT_coverage_version_EQ);
436       if (CoverageVersion.size() != 4) {
437         Diags.Report(diag::err_drv_invalid_value)
438             << Args.getLastArg(OPT_coverage_version_EQ)->getAsString(Args)
439             << CoverageVersion;
440       } else {
441         memcpy(Opts.CoverageVersion, CoverageVersion.data(), 4);
442       }
443     }
444   }
445 
446   Opts.InstrumentFunctions = Args.hasArg(OPT_finstrument_functions);
447   Opts.InstrumentForProfiling = Args.hasArg(OPT_pg);
448   Opts.EmitOpenCLArgMetadata = Args.hasArg(OPT_cl_kernel_arg_info);
449   Opts.CompressDebugSections = Args.hasArg(OPT_compress_debug_sections);
450   Opts.DebugCompilationDir = Args.getLastArgValue(OPT_fdebug_compilation_dir);
451   Opts.LinkBitcodeFile = Args.getLastArgValue(OPT_mlink_bitcode_file);
452   Opts.SanitizerBlacklistFile = Args.getLastArgValue(OPT_fsanitize_blacklist);
453   Opts.SanitizeMemoryTrackOrigins =
454       getLastArgIntValue(Args, OPT_fsanitize_memory_track_origins_EQ, 0, Diags);
455   Opts.SanitizeUndefinedTrapOnError =
456       Args.hasArg(OPT_fsanitize_undefined_trap_on_error);
457   Opts.SSPBufferSize =
458       getLastArgIntValue(Args, OPT_stack_protector_buffer_size, 8, Diags);
459   Opts.StackRealignment = Args.hasArg(OPT_mstackrealign);
460   if (Arg *A = Args.getLastArg(OPT_mstack_alignment)) {
461     StringRef Val = A->getValue();
462     unsigned StackAlignment = Opts.StackAlignment;
463     Val.getAsInteger(10, StackAlignment);
464     Opts.StackAlignment = StackAlignment;
465   }
466 
467   if (Arg *A = Args.getLastArg(OPT_fobjc_dispatch_method_EQ)) {
468     StringRef Name = A->getValue();
469     unsigned Method = llvm::StringSwitch<unsigned>(Name)
470       .Case("legacy", CodeGenOptions::Legacy)
471       .Case("non-legacy", CodeGenOptions::NonLegacy)
472       .Case("mixed", CodeGenOptions::Mixed)
473       .Default(~0U);
474     if (Method == ~0U) {
475       Diags.Report(diag::err_drv_invalid_value) << A->getAsString(Args) << Name;
476       Success = false;
477     } else {
478       Opts.setObjCDispatchMethod(
479         static_cast<CodeGenOptions::ObjCDispatchMethodKind>(Method));
480     }
481   }
482 
483   if (Arg *A = Args.getLastArg(OPT_ftlsmodel_EQ)) {
484     StringRef Name = A->getValue();
485     unsigned Model = llvm::StringSwitch<unsigned>(Name)
486         .Case("global-dynamic", CodeGenOptions::GeneralDynamicTLSModel)
487         .Case("local-dynamic", CodeGenOptions::LocalDynamicTLSModel)
488         .Case("initial-exec", CodeGenOptions::InitialExecTLSModel)
489         .Case("local-exec", CodeGenOptions::LocalExecTLSModel)
490         .Default(~0U);
491     if (Model == ~0U) {
492       Diags.Report(diag::err_drv_invalid_value) << A->getAsString(Args) << Name;
493       Success = false;
494     } else {
495       Opts.setDefaultTLSModel(static_cast<CodeGenOptions::TLSModel>(Model));
496     }
497   }
498 
499   if (Arg *A = Args.getLastArg(OPT_ffp_contract)) {
500     StringRef Val = A->getValue();
501     if (Val == "fast")
502       Opts.setFPContractMode(CodeGenOptions::FPC_Fast);
503     else if (Val == "on")
504       Opts.setFPContractMode(CodeGenOptions::FPC_On);
505     else if (Val == "off")
506       Opts.setFPContractMode(CodeGenOptions::FPC_Off);
507     else
508       Diags.Report(diag::err_drv_invalid_value) << A->getAsString(Args) << Val;
509   }
510 
511   if (Arg *A = Args.getLastArg(OPT_fpcc_struct_return, OPT_freg_struct_return)) {
512     if (A->getOption().matches(OPT_fpcc_struct_return)) {
513       Opts.setStructReturnConvention(CodeGenOptions::SRCK_OnStack);
514     } else {
515       assert(A->getOption().matches(OPT_freg_struct_return));
516       Opts.setStructReturnConvention(CodeGenOptions::SRCK_InRegs);
517     }
518   }
519 
520   Opts.DependentLibraries = Args.getAllArgValues(OPT_dependent_lib);
521 
522   if (Arg *A = Args.getLastArg(OPT_Rpass_EQ)) {
523     StringRef Val = A->getValue();
524     std::string RegexError;
525     Opts.OptimizationRemarkPattern = std::make_shared<llvm::Regex>(Val);
526     if (!Opts.OptimizationRemarkPattern->isValid(RegexError)) {
527       Diags.Report(diag::err_drv_optimization_remark_pattern)
528           << RegexError << A->getAsString(Args);
529       Opts.OptimizationRemarkPattern.reset();
530     }
531   }
532 
533   return Success;
534 }
535 
536 static void ParseDependencyOutputArgs(DependencyOutputOptions &Opts,
537                                       ArgList &Args) {
538   using namespace options;
539   Opts.OutputFile = Args.getLastArgValue(OPT_dependency_file);
540   Opts.Targets = Args.getAllArgValues(OPT_MT);
541   Opts.IncludeSystemHeaders = Args.hasArg(OPT_sys_header_deps);
542   Opts.IncludeModuleFiles = Args.hasArg(OPT_module_file_deps);
543   Opts.UsePhonyTargets = Args.hasArg(OPT_MP);
544   Opts.ShowHeaderIncludes = Args.hasArg(OPT_H);
545   Opts.HeaderIncludeOutputFile = Args.getLastArgValue(OPT_header_include_file);
546   Opts.AddMissingHeaderDeps = Args.hasArg(OPT_MG);
547   Opts.PrintShowIncludes = Args.hasArg(OPT_show_includes);
548   Opts.DOTOutputFile = Args.getLastArgValue(OPT_dependency_dot);
549 }
550 
551 bool clang::ParseDiagnosticArgs(DiagnosticOptions &Opts, ArgList &Args,
552                                 DiagnosticsEngine *Diags) {
553   using namespace options;
554   bool Success = true;
555 
556   Opts.DiagnosticLogFile = Args.getLastArgValue(OPT_diagnostic_log_file);
557   Opts.DiagnosticSerializationFile =
558     Args.getLastArgValue(OPT_diagnostic_serialized_file);
559   Opts.IgnoreWarnings = Args.hasArg(OPT_w);
560   Opts.NoRewriteMacros = Args.hasArg(OPT_Wno_rewrite_macros);
561   Opts.Pedantic = Args.hasArg(OPT_pedantic);
562   Opts.PedanticErrors = Args.hasArg(OPT_pedantic_errors);
563   Opts.ShowCarets = !Args.hasArg(OPT_fno_caret_diagnostics);
564   Opts.ShowColors = Args.hasArg(OPT_fcolor_diagnostics);
565   Opts.ShowColumn = Args.hasFlag(OPT_fshow_column,
566                                  OPT_fno_show_column,
567                                  /*Default=*/true);
568   Opts.ShowFixits = !Args.hasArg(OPT_fno_diagnostics_fixit_info);
569   Opts.ShowLocation = !Args.hasArg(OPT_fno_show_source_location);
570   Opts.ShowOptionNames = Args.hasArg(OPT_fdiagnostics_show_option);
571 
572   llvm::sys::Process::UseANSIEscapeCodes(Args.hasArg(OPT_fansi_escape_codes));
573 
574   // Default behavior is to not to show note include stacks.
575   Opts.ShowNoteIncludeStack = false;
576   if (Arg *A = Args.getLastArg(OPT_fdiagnostics_show_note_include_stack,
577                                OPT_fno_diagnostics_show_note_include_stack))
578     if (A->getOption().matches(OPT_fdiagnostics_show_note_include_stack))
579       Opts.ShowNoteIncludeStack = true;
580 
581   StringRef ShowOverloads =
582     Args.getLastArgValue(OPT_fshow_overloads_EQ, "all");
583   if (ShowOverloads == "best")
584     Opts.setShowOverloads(Ovl_Best);
585   else if (ShowOverloads == "all")
586     Opts.setShowOverloads(Ovl_All);
587   else {
588     Success = false;
589     if (Diags)
590       Diags->Report(diag::err_drv_invalid_value)
591       << Args.getLastArg(OPT_fshow_overloads_EQ)->getAsString(Args)
592       << ShowOverloads;
593   }
594 
595   StringRef ShowCategory =
596     Args.getLastArgValue(OPT_fdiagnostics_show_category, "none");
597   if (ShowCategory == "none")
598     Opts.ShowCategories = 0;
599   else if (ShowCategory == "id")
600     Opts.ShowCategories = 1;
601   else if (ShowCategory == "name")
602     Opts.ShowCategories = 2;
603   else {
604     Success = false;
605     if (Diags)
606       Diags->Report(diag::err_drv_invalid_value)
607       << Args.getLastArg(OPT_fdiagnostics_show_category)->getAsString(Args)
608       << ShowCategory;
609   }
610 
611   StringRef Format =
612     Args.getLastArgValue(OPT_fdiagnostics_format, "clang");
613   if (Format == "clang")
614     Opts.setFormat(DiagnosticOptions::Clang);
615   else if (Format == "msvc")
616     Opts.setFormat(DiagnosticOptions::Msvc);
617   else if (Format == "msvc-fallback") {
618     Opts.setFormat(DiagnosticOptions::Msvc);
619     Opts.CLFallbackMode = true;
620   } else if (Format == "vi")
621     Opts.setFormat(DiagnosticOptions::Vi);
622   else {
623     Success = false;
624     if (Diags)
625       Diags->Report(diag::err_drv_invalid_value)
626       << Args.getLastArg(OPT_fdiagnostics_format)->getAsString(Args)
627       << Format;
628   }
629 
630   Opts.ShowSourceRanges = Args.hasArg(OPT_fdiagnostics_print_source_range_info);
631   Opts.ShowParseableFixits = Args.hasArg(OPT_fdiagnostics_parseable_fixits);
632   Opts.ShowPresumedLoc = !Args.hasArg(OPT_fno_diagnostics_use_presumed_location);
633   Opts.VerifyDiagnostics = Args.hasArg(OPT_verify);
634   Opts.ElideType = !Args.hasArg(OPT_fno_elide_type);
635   Opts.ShowTemplateTree = Args.hasArg(OPT_fdiagnostics_show_template_tree);
636   Opts.ErrorLimit = getLastArgIntValue(Args, OPT_ferror_limit, 0, Diags);
637   Opts.MacroBacktraceLimit =
638       getLastArgIntValue(Args, OPT_fmacro_backtrace_limit,
639                          DiagnosticOptions::DefaultMacroBacktraceLimit, Diags);
640   Opts.TemplateBacktraceLimit = getLastArgIntValue(
641       Args, OPT_ftemplate_backtrace_limit,
642       DiagnosticOptions::DefaultTemplateBacktraceLimit, Diags);
643   Opts.ConstexprBacktraceLimit = getLastArgIntValue(
644       Args, OPT_fconstexpr_backtrace_limit,
645       DiagnosticOptions::DefaultConstexprBacktraceLimit, Diags);
646   Opts.TabStop = getLastArgIntValue(Args, OPT_ftabstop,
647                                     DiagnosticOptions::DefaultTabStop, Diags);
648   if (Opts.TabStop == 0 || Opts.TabStop > DiagnosticOptions::MaxTabStop) {
649     Opts.TabStop = DiagnosticOptions::DefaultTabStop;
650     if (Diags)
651       Diags->Report(diag::warn_ignoring_ftabstop_value)
652       << Opts.TabStop << DiagnosticOptions::DefaultTabStop;
653   }
654   Opts.MessageLength = getLastArgIntValue(Args, OPT_fmessage_length, 0, Diags);
655   addWarningArgs(Args, Opts.Warnings);
656 
657   return Success;
658 }
659 
660 static void ParseFileSystemArgs(FileSystemOptions &Opts, ArgList &Args) {
661   Opts.WorkingDir = Args.getLastArgValue(OPT_working_directory);
662 }
663 
664 static InputKind ParseFrontendArgs(FrontendOptions &Opts, ArgList &Args,
665                                    DiagnosticsEngine &Diags) {
666   using namespace options;
667   Opts.ProgramAction = frontend::ParseSyntaxOnly;
668   if (const Arg *A = Args.getLastArg(OPT_Action_Group)) {
669     switch (A->getOption().getID()) {
670     default:
671       llvm_unreachable("Invalid option in group!");
672     case OPT_ast_list:
673       Opts.ProgramAction = frontend::ASTDeclList; break;
674     case OPT_ast_dump:
675       Opts.ProgramAction = frontend::ASTDump; break;
676     case OPT_ast_print:
677       Opts.ProgramAction = frontend::ASTPrint; break;
678     case OPT_ast_view:
679       Opts.ProgramAction = frontend::ASTView; break;
680     case OPT_dump_raw_tokens:
681       Opts.ProgramAction = frontend::DumpRawTokens; break;
682     case OPT_dump_tokens:
683       Opts.ProgramAction = frontend::DumpTokens; break;
684     case OPT_S:
685       Opts.ProgramAction = frontend::EmitAssembly; break;
686     case OPT_emit_llvm_bc:
687       Opts.ProgramAction = frontend::EmitBC; break;
688     case OPT_emit_html:
689       Opts.ProgramAction = frontend::EmitHTML; break;
690     case OPT_emit_llvm:
691       Opts.ProgramAction = frontend::EmitLLVM; break;
692     case OPT_emit_llvm_only:
693       Opts.ProgramAction = frontend::EmitLLVMOnly; break;
694     case OPT_emit_codegen_only:
695       Opts.ProgramAction = frontend::EmitCodeGenOnly; break;
696     case OPT_emit_obj:
697       Opts.ProgramAction = frontend::EmitObj; break;
698     case OPT_fixit_EQ:
699       Opts.FixItSuffix = A->getValue();
700       // fall-through!
701     case OPT_fixit:
702       Opts.ProgramAction = frontend::FixIt; break;
703     case OPT_emit_module:
704       Opts.ProgramAction = frontend::GenerateModule; break;
705     case OPT_emit_pch:
706       Opts.ProgramAction = frontend::GeneratePCH; break;
707     case OPT_emit_pth:
708       Opts.ProgramAction = frontend::GeneratePTH; break;
709     case OPT_init_only:
710       Opts.ProgramAction = frontend::InitOnly; break;
711     case OPT_fsyntax_only:
712       Opts.ProgramAction = frontend::ParseSyntaxOnly; break;
713     case OPT_module_file_info:
714       Opts.ProgramAction = frontend::ModuleFileInfo; break;
715     case OPT_verify_pch:
716       Opts.ProgramAction = frontend::VerifyPCH; break;
717     case OPT_print_decl_contexts:
718       Opts.ProgramAction = frontend::PrintDeclContext; break;
719     case OPT_print_preamble:
720       Opts.ProgramAction = frontend::PrintPreamble; break;
721     case OPT_E:
722       Opts.ProgramAction = frontend::PrintPreprocessedInput; break;
723     case OPT_rewrite_macros:
724       Opts.ProgramAction = frontend::RewriteMacros; break;
725     case OPT_rewrite_objc:
726       Opts.ProgramAction = frontend::RewriteObjC; break;
727     case OPT_rewrite_test:
728       Opts.ProgramAction = frontend::RewriteTest; break;
729     case OPT_analyze:
730       Opts.ProgramAction = frontend::RunAnalysis; break;
731     case OPT_migrate:
732       Opts.ProgramAction = frontend::MigrateSource; break;
733     case OPT_Eonly:
734       Opts.ProgramAction = frontend::RunPreprocessorOnly; break;
735     }
736   }
737 
738   if (const Arg* A = Args.getLastArg(OPT_plugin)) {
739     Opts.Plugins.push_back(A->getValue(0));
740     Opts.ProgramAction = frontend::PluginAction;
741     Opts.ActionName = A->getValue();
742 
743     for (arg_iterator it = Args.filtered_begin(OPT_plugin_arg),
744            end = Args.filtered_end(); it != end; ++it) {
745       if ((*it)->getValue(0) == Opts.ActionName)
746         Opts.PluginArgs.push_back((*it)->getValue(1));
747     }
748   }
749 
750   Opts.AddPluginActions = Args.getAllArgValues(OPT_add_plugin);
751   Opts.AddPluginArgs.resize(Opts.AddPluginActions.size());
752   for (int i = 0, e = Opts.AddPluginActions.size(); i != e; ++i) {
753     for (arg_iterator it = Args.filtered_begin(OPT_plugin_arg),
754            end = Args.filtered_end(); it != end; ++it) {
755       if ((*it)->getValue(0) == Opts.AddPluginActions[i])
756         Opts.AddPluginArgs[i].push_back((*it)->getValue(1));
757     }
758   }
759 
760   if (const Arg *A = Args.getLastArg(OPT_code_completion_at)) {
761     Opts.CodeCompletionAt =
762       ParsedSourceLocation::FromString(A->getValue());
763     if (Opts.CodeCompletionAt.FileName.empty())
764       Diags.Report(diag::err_drv_invalid_value)
765         << A->getAsString(Args) << A->getValue();
766   }
767   Opts.DisableFree = Args.hasArg(OPT_disable_free);
768 
769   Opts.OutputFile = Args.getLastArgValue(OPT_o);
770   Opts.Plugins = Args.getAllArgValues(OPT_load);
771   Opts.RelocatablePCH = Args.hasArg(OPT_relocatable_pch);
772   Opts.ShowHelp = Args.hasArg(OPT_help);
773   Opts.ShowStats = Args.hasArg(OPT_print_stats);
774   Opts.ShowTimers = Args.hasArg(OPT_ftime_report);
775   Opts.ShowVersion = Args.hasArg(OPT_version);
776   Opts.ASTMergeFiles = Args.getAllArgValues(OPT_ast_merge);
777   Opts.LLVMArgs = Args.getAllArgValues(OPT_mllvm);
778   Opts.FixWhatYouCan = Args.hasArg(OPT_fix_what_you_can);
779   Opts.FixOnlyWarnings = Args.hasArg(OPT_fix_only_warnings);
780   Opts.FixAndRecompile = Args.hasArg(OPT_fixit_recompile);
781   Opts.FixToTemporaries = Args.hasArg(OPT_fixit_to_temp);
782   Opts.ASTDumpFilter = Args.getLastArgValue(OPT_ast_dump_filter);
783   Opts.ASTDumpLookups = Args.hasArg(OPT_ast_dump_lookups);
784   Opts.UseGlobalModuleIndex = !Args.hasArg(OPT_fno_modules_global_index);
785   Opts.GenerateGlobalModuleIndex = Opts.UseGlobalModuleIndex;
786 
787   Opts.CodeCompleteOpts.IncludeMacros
788     = Args.hasArg(OPT_code_completion_macros);
789   Opts.CodeCompleteOpts.IncludeCodePatterns
790     = Args.hasArg(OPT_code_completion_patterns);
791   Opts.CodeCompleteOpts.IncludeGlobals
792     = !Args.hasArg(OPT_no_code_completion_globals);
793   Opts.CodeCompleteOpts.IncludeBriefComments
794     = Args.hasArg(OPT_code_completion_brief_comments);
795 
796   Opts.OverrideRecordLayoutsFile
797     = Args.getLastArgValue(OPT_foverride_record_layout_EQ);
798   if (const Arg *A = Args.getLastArg(OPT_arcmt_check,
799                                      OPT_arcmt_modify,
800                                      OPT_arcmt_migrate)) {
801     switch (A->getOption().getID()) {
802     default:
803       llvm_unreachable("missed a case");
804     case OPT_arcmt_check:
805       Opts.ARCMTAction = FrontendOptions::ARCMT_Check;
806       break;
807     case OPT_arcmt_modify:
808       Opts.ARCMTAction = FrontendOptions::ARCMT_Modify;
809       break;
810     case OPT_arcmt_migrate:
811       Opts.ARCMTAction = FrontendOptions::ARCMT_Migrate;
812       break;
813     }
814   }
815   Opts.MTMigrateDir = Args.getLastArgValue(OPT_mt_migrate_directory);
816   Opts.ARCMTMigrateReportOut
817     = Args.getLastArgValue(OPT_arcmt_migrate_report_output);
818   Opts.ARCMTMigrateEmitARCErrors
819     = Args.hasArg(OPT_arcmt_migrate_emit_arc_errors);
820 
821   if (Args.hasArg(OPT_objcmt_migrate_literals))
822     Opts.ObjCMTAction |= FrontendOptions::ObjCMT_Literals;
823   if (Args.hasArg(OPT_objcmt_migrate_subscripting))
824     Opts.ObjCMTAction |= FrontendOptions::ObjCMT_Subscripting;
825   if (Args.hasArg(OPT_objcmt_migrate_property))
826     Opts.ObjCMTAction |= FrontendOptions::ObjCMT_Property;
827   if (Args.hasArg(OPT_objcmt_migrate_readonly_property))
828     Opts.ObjCMTAction |= FrontendOptions::ObjCMT_ReadonlyProperty;
829   if (Args.hasArg(OPT_objcmt_migrate_readwrite_property))
830     Opts.ObjCMTAction |= FrontendOptions::ObjCMT_ReadwriteProperty;
831   if (Args.hasArg(OPT_objcmt_migrate_annotation))
832     Opts.ObjCMTAction |= FrontendOptions::ObjCMT_Annotation;
833   if (Args.hasArg(OPT_objcmt_returns_innerpointer_property))
834     Opts.ObjCMTAction |= FrontendOptions::ObjCMT_ReturnsInnerPointerProperty;
835   if (Args.hasArg(OPT_objcmt_migrate_instancetype))
836     Opts.ObjCMTAction |= FrontendOptions::ObjCMT_Instancetype;
837   if (Args.hasArg(OPT_objcmt_migrate_nsmacros))
838     Opts.ObjCMTAction |= FrontendOptions::ObjCMT_NsMacros;
839   if (Args.hasArg(OPT_objcmt_migrate_protocol_conformance))
840     Opts.ObjCMTAction |= FrontendOptions::ObjCMT_ProtocolConformance;
841   if (Args.hasArg(OPT_objcmt_atomic_property))
842     Opts.ObjCMTAction |= FrontendOptions::ObjCMT_AtomicProperty;
843   if (Args.hasArg(OPT_objcmt_ns_nonatomic_iosonly))
844     Opts.ObjCMTAction |= FrontendOptions::ObjCMT_NsAtomicIOSOnlyProperty;
845   if (Args.hasArg(OPT_objcmt_migrate_designated_init))
846     Opts.ObjCMTAction |= FrontendOptions::ObjCMT_DesignatedInitializer;
847   if (Args.hasArg(OPT_objcmt_migrate_all))
848     Opts.ObjCMTAction |= FrontendOptions::ObjCMT_MigrateDecls;
849 
850   Opts.ObjCMTWhiteListPath = Args.getLastArgValue(OPT_objcmt_whitelist_dir_path);
851 
852   if (Opts.ARCMTAction != FrontendOptions::ARCMT_None &&
853       Opts.ObjCMTAction != FrontendOptions::ObjCMT_None) {
854     Diags.Report(diag::err_drv_argument_not_allowed_with)
855       << "ARC migration" << "ObjC migration";
856   }
857 
858   InputKind DashX = IK_None;
859   if (const Arg *A = Args.getLastArg(OPT_x)) {
860     DashX = llvm::StringSwitch<InputKind>(A->getValue())
861       .Case("c", IK_C)
862       .Case("cl", IK_OpenCL)
863       .Case("cuda", IK_CUDA)
864       .Case("c++", IK_CXX)
865       .Case("objective-c", IK_ObjC)
866       .Case("objective-c++", IK_ObjCXX)
867       .Case("cpp-output", IK_PreprocessedC)
868       .Case("assembler-with-cpp", IK_Asm)
869       .Case("c++-cpp-output", IK_PreprocessedCXX)
870       .Case("objective-c-cpp-output", IK_PreprocessedObjC)
871       .Case("objc-cpp-output", IK_PreprocessedObjC)
872       .Case("objective-c++-cpp-output", IK_PreprocessedObjCXX)
873       .Case("objc++-cpp-output", IK_PreprocessedObjCXX)
874       .Case("c-header", IK_C)
875       .Case("cl-header", IK_OpenCL)
876       .Case("objective-c-header", IK_ObjC)
877       .Case("c++-header", IK_CXX)
878       .Case("objective-c++-header", IK_ObjCXX)
879       .Cases("ast", "pcm", IK_AST)
880       .Case("ir", IK_LLVM_IR)
881       .Default(IK_None);
882     if (DashX == IK_None)
883       Diags.Report(diag::err_drv_invalid_value)
884         << A->getAsString(Args) << A->getValue();
885   }
886 
887   // '-' is the default input if none is given.
888   std::vector<std::string> Inputs = Args.getAllArgValues(OPT_INPUT);
889   Opts.Inputs.clear();
890   if (Inputs.empty())
891     Inputs.push_back("-");
892   for (unsigned i = 0, e = Inputs.size(); i != e; ++i) {
893     InputKind IK = DashX;
894     if (IK == IK_None) {
895       IK = FrontendOptions::getInputKindForExtension(
896         StringRef(Inputs[i]).rsplit('.').second);
897       // FIXME: Remove this hack.
898       if (i == 0)
899         DashX = IK;
900     }
901     Opts.Inputs.push_back(FrontendInputFile(Inputs[i], IK));
902   }
903 
904   return DashX;
905 }
906 
907 std::string CompilerInvocation::GetResourcesPath(const char *Argv0,
908                                                  void *MainAddr) {
909   SmallString<128> P(llvm::sys::fs::getMainExecutable(Argv0, MainAddr));
910 
911   if (!P.empty()) {
912     llvm::sys::path::remove_filename(P); // Remove /clang from foo/bin/clang
913     llvm::sys::path::remove_filename(P); // Remove /bin   from foo/bin
914 
915     // Get foo/lib/clang/<version>/include
916     llvm::sys::path::append(P, "lib", "clang", CLANG_VERSION_STRING);
917   }
918 
919   return P.str();
920 }
921 
922 static void ParseHeaderSearchArgs(HeaderSearchOptions &Opts, ArgList &Args) {
923   using namespace options;
924   Opts.Sysroot = Args.getLastArgValue(OPT_isysroot, "/");
925   Opts.Verbose = Args.hasArg(OPT_v);
926   Opts.UseBuiltinIncludes = !Args.hasArg(OPT_nobuiltininc);
927   Opts.UseStandardSystemIncludes = !Args.hasArg(OPT_nostdsysteminc);
928   Opts.UseStandardCXXIncludes = !Args.hasArg(OPT_nostdincxx);
929   if (const Arg *A = Args.getLastArg(OPT_stdlib_EQ))
930     Opts.UseLibcxx = (strcmp(A->getValue(), "libc++") == 0);
931   Opts.ResourceDir = Args.getLastArgValue(OPT_resource_dir);
932   Opts.ModuleCachePath = Args.getLastArgValue(OPT_fmodules_cache_path);
933   Opts.ModuleUserBuildPath = Args.getLastArgValue(OPT_fmodules_user_build_path);
934   Opts.DisableModuleHash = Args.hasArg(OPT_fdisable_module_hash);
935   // -fmodules implies -fmodule-maps
936   Opts.ModuleMaps = Args.hasArg(OPT_fmodule_maps) || Args.hasArg(OPT_fmodules);
937   Opts.ModuleCachePruneInterval =
938       getLastArgIntValue(Args, OPT_fmodules_prune_interval, 7 * 24 * 60 * 60);
939   Opts.ModuleCachePruneAfter =
940       getLastArgIntValue(Args, OPT_fmodules_prune_after, 31 * 24 * 60 * 60);
941   Opts.ModulesValidateOncePerBuildSession =
942       Args.hasArg(OPT_fmodules_validate_once_per_build_session);
943   Opts.BuildSessionTimestamp =
944       getLastArgUInt64Value(Args, OPT_fbuild_session_timestamp, 0);
945   Opts.ModulesValidateSystemHeaders =
946       Args.hasArg(OPT_fmodules_validate_system_headers);
947 
948   for (arg_iterator it = Args.filtered_begin(OPT_fmodules_ignore_macro),
949                     ie = Args.filtered_end();
950        it != ie; ++it) {
951     StringRef MacroDef = (*it)->getValue();
952     Opts.ModulesIgnoreMacros.insert(MacroDef.split('=').first);
953   }
954   std::vector<std::string> ModuleMapFiles =
955       Args.getAllArgValues(OPT_fmodule_map_file);
956   Opts.ModuleMapFiles.insert(ModuleMapFiles.begin(), ModuleMapFiles.end());
957 
958   // Add -I..., -F..., and -index-header-map options in order.
959   bool IsIndexHeaderMap = false;
960   for (arg_iterator it = Args.filtered_begin(OPT_I, OPT_F,
961                                              OPT_index_header_map),
962        ie = Args.filtered_end(); it != ie; ++it) {
963     if ((*it)->getOption().matches(OPT_index_header_map)) {
964       // -index-header-map applies to the next -I or -F.
965       IsIndexHeaderMap = true;
966       continue;
967     }
968 
969     frontend::IncludeDirGroup Group
970       = IsIndexHeaderMap? frontend::IndexHeaderMap : frontend::Angled;
971 
972     Opts.AddPath((*it)->getValue(), Group,
973                  /*IsFramework=*/ (*it)->getOption().matches(OPT_F), true);
974     IsIndexHeaderMap = false;
975   }
976 
977   // Add -iprefix/-iwithprefix/-iwithprefixbefore options.
978   StringRef Prefix = ""; // FIXME: This isn't the correct default prefix.
979   for (arg_iterator it = Args.filtered_begin(OPT_iprefix, OPT_iwithprefix,
980                                              OPT_iwithprefixbefore),
981          ie = Args.filtered_end(); it != ie; ++it) {
982     const Arg *A = *it;
983     if (A->getOption().matches(OPT_iprefix))
984       Prefix = A->getValue();
985     else if (A->getOption().matches(OPT_iwithprefix))
986       Opts.AddPath(Prefix.str() + A->getValue(),
987                    frontend::After, false, true);
988     else
989       Opts.AddPath(Prefix.str() + A->getValue(),
990                    frontend::Angled, false, true);
991   }
992 
993   for (arg_iterator it = Args.filtered_begin(OPT_idirafter),
994          ie = Args.filtered_end(); it != ie; ++it)
995     Opts.AddPath((*it)->getValue(), frontend::After, false, true);
996   for (arg_iterator it = Args.filtered_begin(OPT_iquote),
997          ie = Args.filtered_end(); it != ie; ++it)
998     Opts.AddPath((*it)->getValue(), frontend::Quoted, false, true);
999   for (arg_iterator it = Args.filtered_begin(OPT_isystem,
1000          OPT_iwithsysroot), ie = Args.filtered_end(); it != ie; ++it)
1001     Opts.AddPath((*it)->getValue(), frontend::System, false,
1002                  !(*it)->getOption().matches(OPT_iwithsysroot));
1003   for (arg_iterator it = Args.filtered_begin(OPT_iframework),
1004          ie = Args.filtered_end(); it != ie; ++it)
1005     Opts.AddPath((*it)->getValue(), frontend::System, true, true);
1006 
1007   // Add the paths for the various language specific isystem flags.
1008   for (arg_iterator it = Args.filtered_begin(OPT_c_isystem),
1009        ie = Args.filtered_end(); it != ie; ++it)
1010     Opts.AddPath((*it)->getValue(), frontend::CSystem, false, true);
1011   for (arg_iterator it = Args.filtered_begin(OPT_cxx_isystem),
1012        ie = Args.filtered_end(); it != ie; ++it)
1013     Opts.AddPath((*it)->getValue(), frontend::CXXSystem, false, true);
1014   for (arg_iterator it = Args.filtered_begin(OPT_objc_isystem),
1015        ie = Args.filtered_end(); it != ie; ++it)
1016     Opts.AddPath((*it)->getValue(), frontend::ObjCSystem, false,true);
1017   for (arg_iterator it = Args.filtered_begin(OPT_objcxx_isystem),
1018        ie = Args.filtered_end(); it != ie; ++it)
1019     Opts.AddPath((*it)->getValue(), frontend::ObjCXXSystem, false, true);
1020 
1021   // Add the internal paths from a driver that detects standard include paths.
1022   for (arg_iterator I = Args.filtered_begin(OPT_internal_isystem,
1023                                             OPT_internal_externc_isystem),
1024                     E = Args.filtered_end();
1025        I != E; ++I) {
1026     frontend::IncludeDirGroup Group = frontend::System;
1027     if ((*I)->getOption().matches(OPT_internal_externc_isystem))
1028       Group = frontend::ExternCSystem;
1029     Opts.AddPath((*I)->getValue(), Group, false, true);
1030   }
1031 
1032   // Add the path prefixes which are implicitly treated as being system headers.
1033   for (arg_iterator I = Args.filtered_begin(OPT_system_header_prefix,
1034                                             OPT_no_system_header_prefix),
1035                     E = Args.filtered_end();
1036        I != E; ++I)
1037     Opts.AddSystemHeaderPrefix(
1038         (*I)->getValue(), (*I)->getOption().matches(OPT_system_header_prefix));
1039 
1040   for (arg_iterator I = Args.filtered_begin(OPT_ivfsoverlay),
1041        E = Args.filtered_end(); I != E; ++I)
1042     Opts.AddVFSOverlayFile((*I)->getValue());
1043 }
1044 
1045 void CompilerInvocation::setLangDefaults(LangOptions &Opts, InputKind IK,
1046                                          LangStandard::Kind LangStd) {
1047   // Set some properties which depend solely on the input kind; it would be nice
1048   // to move these to the language standard, and have the driver resolve the
1049   // input kind + language standard.
1050   if (IK == IK_Asm) {
1051     Opts.AsmPreprocessor = 1;
1052   } else if (IK == IK_ObjC ||
1053              IK == IK_ObjCXX ||
1054              IK == IK_PreprocessedObjC ||
1055              IK == IK_PreprocessedObjCXX) {
1056     Opts.ObjC1 = Opts.ObjC2 = 1;
1057   }
1058 
1059   if (LangStd == LangStandard::lang_unspecified) {
1060     // Based on the base language, pick one.
1061     switch (IK) {
1062     case IK_None:
1063     case IK_AST:
1064     case IK_LLVM_IR:
1065       llvm_unreachable("Invalid input kind!");
1066     case IK_OpenCL:
1067       LangStd = LangStandard::lang_opencl;
1068       break;
1069     case IK_CUDA:
1070       LangStd = LangStandard::lang_cuda;
1071       break;
1072     case IK_Asm:
1073     case IK_C:
1074     case IK_PreprocessedC:
1075     case IK_ObjC:
1076     case IK_PreprocessedObjC:
1077       LangStd = LangStandard::lang_gnu99;
1078       break;
1079     case IK_CXX:
1080     case IK_PreprocessedCXX:
1081     case IK_ObjCXX:
1082     case IK_PreprocessedObjCXX:
1083       LangStd = LangStandard::lang_gnucxx98;
1084       break;
1085     }
1086   }
1087 
1088   const LangStandard &Std = LangStandard::getLangStandardForKind(LangStd);
1089   Opts.LineComment = Std.hasLineComments();
1090   Opts.C99 = Std.isC99();
1091   Opts.C11 = Std.isC11();
1092   Opts.CPlusPlus = Std.isCPlusPlus();
1093   Opts.CPlusPlus11 = Std.isCPlusPlus11();
1094   Opts.CPlusPlus1y = Std.isCPlusPlus1y();
1095   Opts.Digraphs = Std.hasDigraphs();
1096   Opts.GNUMode = Std.isGNUMode();
1097   Opts.GNUInline = !Std.isC99();
1098   Opts.HexFloats = Std.hasHexFloats();
1099   Opts.ImplicitInt = Std.hasImplicitInt();
1100 
1101   // Set OpenCL Version.
1102   if (LangStd == LangStandard::lang_opencl) {
1103     Opts.OpenCL = 1;
1104     Opts.OpenCLVersion = 100;
1105   }
1106   else if (LangStd == LangStandard::lang_opencl11) {
1107       Opts.OpenCL = 1;
1108       Opts.OpenCLVersion = 110;
1109   }
1110   else if (LangStd == LangStandard::lang_opencl12) {
1111     Opts.OpenCL = 1;
1112     Opts.OpenCLVersion = 120;
1113   }
1114 
1115   // OpenCL has some additional defaults.
1116   if (Opts.OpenCL) {
1117     Opts.AltiVec = 0;
1118     Opts.CXXOperatorNames = 1;
1119     Opts.LaxVectorConversions = 0;
1120     Opts.DefaultFPContract = 1;
1121     Opts.NativeHalfType = 1;
1122   }
1123 
1124   if (LangStd == LangStandard::lang_cuda)
1125     Opts.CUDA = 1;
1126 
1127   // OpenCL and C++ both have bool, true, false keywords.
1128   Opts.Bool = Opts.OpenCL || Opts.CPlusPlus;
1129 
1130   // OpenCL has half keyword
1131   Opts.Half = Opts.OpenCL;
1132 
1133   // C++ has wchar_t keyword.
1134   Opts.WChar = Opts.CPlusPlus;
1135 
1136   Opts.GNUKeywords = Opts.GNUMode;
1137   Opts.CXXOperatorNames = Opts.CPlusPlus;
1138 
1139   // Mimicing gcc's behavior, trigraphs are only enabled if -trigraphs
1140   // is specified, or -std is set to a conforming mode.
1141   Opts.Trigraphs = !Opts.GNUMode;
1142 
1143   Opts.DollarIdents = !Opts.AsmPreprocessor;
1144 
1145   // C++1y onwards has sized global deallocation functions.
1146   Opts.SizedDeallocation = Opts.CPlusPlus1y;
1147 }
1148 
1149 /// Attempt to parse a visibility value out of the given argument.
1150 static Visibility parseVisibility(Arg *arg, ArgList &args,
1151                                   DiagnosticsEngine &diags) {
1152   StringRef value = arg->getValue();
1153   if (value == "default") {
1154     return DefaultVisibility;
1155   } else if (value == "hidden") {
1156     return HiddenVisibility;
1157   } else if (value == "protected") {
1158     // FIXME: diagnose if target does not support protected visibility
1159     return ProtectedVisibility;
1160   }
1161 
1162   diags.Report(diag::err_drv_invalid_value)
1163     << arg->getAsString(args) << value;
1164   return DefaultVisibility;
1165 }
1166 
1167 static void ParseLangArgs(LangOptions &Opts, ArgList &Args, InputKind IK,
1168                           DiagnosticsEngine &Diags) {
1169   // FIXME: Cleanup per-file based stuff.
1170   LangStandard::Kind LangStd = LangStandard::lang_unspecified;
1171   if (const Arg *A = Args.getLastArg(OPT_std_EQ)) {
1172     LangStd = llvm::StringSwitch<LangStandard::Kind>(A->getValue())
1173 #define LANGSTANDARD(id, name, desc, features) \
1174       .Case(name, LangStandard::lang_##id)
1175 #include "clang/Frontend/LangStandards.def"
1176       .Default(LangStandard::lang_unspecified);
1177     if (LangStd == LangStandard::lang_unspecified)
1178       Diags.Report(diag::err_drv_invalid_value)
1179         << A->getAsString(Args) << A->getValue();
1180     else {
1181       // Valid standard, check to make sure language and standard are
1182       // compatible.
1183       const LangStandard &Std = LangStandard::getLangStandardForKind(LangStd);
1184       switch (IK) {
1185       case IK_C:
1186       case IK_ObjC:
1187       case IK_PreprocessedC:
1188       case IK_PreprocessedObjC:
1189         if (!(Std.isC89() || Std.isC99()))
1190           Diags.Report(diag::err_drv_argument_not_allowed_with)
1191             << A->getAsString(Args) << "C/ObjC";
1192         break;
1193       case IK_CXX:
1194       case IK_ObjCXX:
1195       case IK_PreprocessedCXX:
1196       case IK_PreprocessedObjCXX:
1197         if (!Std.isCPlusPlus())
1198           Diags.Report(diag::err_drv_argument_not_allowed_with)
1199             << A->getAsString(Args) << "C++/ObjC++";
1200         break;
1201       case IK_OpenCL:
1202         if (!Std.isC99())
1203           Diags.Report(diag::err_drv_argument_not_allowed_with)
1204             << A->getAsString(Args) << "OpenCL";
1205         break;
1206       case IK_CUDA:
1207         if (!Std.isCPlusPlus())
1208           Diags.Report(diag::err_drv_argument_not_allowed_with)
1209             << A->getAsString(Args) << "CUDA";
1210         break;
1211       default:
1212         break;
1213       }
1214     }
1215   }
1216 
1217   // -cl-std only applies for OpenCL language standards.
1218   // Override the -std option in this case.
1219   if (const Arg *A = Args.getLastArg(OPT_cl_std_EQ)) {
1220     LangStandard::Kind OpenCLLangStd
1221     = llvm::StringSwitch<LangStandard::Kind>(A->getValue())
1222     .Case("CL", LangStandard::lang_opencl)
1223     .Case("CL1.1", LangStandard::lang_opencl11)
1224     .Case("CL1.2", LangStandard::lang_opencl12)
1225     .Default(LangStandard::lang_unspecified);
1226 
1227     if (OpenCLLangStd == LangStandard::lang_unspecified) {
1228       Diags.Report(diag::err_drv_invalid_value)
1229       << A->getAsString(Args) << A->getValue();
1230     }
1231     else
1232       LangStd = OpenCLLangStd;
1233   }
1234 
1235   CompilerInvocation::setLangDefaults(Opts, IK, LangStd);
1236 
1237   // We abuse '-f[no-]gnu-keywords' to force overriding all GNU-extension
1238   // keywords. This behavior is provided by GCC's poorly named '-fasm' flag,
1239   // while a subset (the non-C++ GNU keywords) is provided by GCC's
1240   // '-fgnu-keywords'. Clang conflates the two for simplicity under the single
1241   // name, as it doesn't seem a useful distinction.
1242   Opts.GNUKeywords = Args.hasFlag(OPT_fgnu_keywords, OPT_fno_gnu_keywords,
1243                                   Opts.GNUKeywords);
1244 
1245   if (Args.hasArg(OPT_fno_operator_names))
1246     Opts.CXXOperatorNames = 0;
1247 
1248   if (Opts.ObjC1) {
1249     if (Arg *arg = Args.getLastArg(OPT_fobjc_runtime_EQ)) {
1250       StringRef value = arg->getValue();
1251       if (Opts.ObjCRuntime.tryParse(value))
1252         Diags.Report(diag::err_drv_unknown_objc_runtime) << value;
1253     }
1254 
1255     if (Args.hasArg(OPT_fobjc_gc_only))
1256       Opts.setGC(LangOptions::GCOnly);
1257     else if (Args.hasArg(OPT_fobjc_gc))
1258       Opts.setGC(LangOptions::HybridGC);
1259     else if (Args.hasArg(OPT_fobjc_arc)) {
1260       Opts.ObjCAutoRefCount = 1;
1261       if (!Opts.ObjCRuntime.allowsARC())
1262         Diags.Report(diag::err_arc_unsupported_on_runtime);
1263 
1264       // Only set ObjCARCWeak if ARC is enabled.
1265       if (Args.hasArg(OPT_fobjc_runtime_has_weak))
1266         Opts.ObjCARCWeak = 1;
1267       else
1268         Opts.ObjCARCWeak = Opts.ObjCRuntime.allowsWeak();
1269     }
1270 
1271     if (Args.hasArg(OPT_fno_objc_infer_related_result_type))
1272       Opts.ObjCInferRelatedResultType = 0;
1273 
1274     if (Args.hasArg(OPT_fobjc_subscripting_legacy_runtime))
1275       Opts.ObjCSubscriptingLegacyRuntime =
1276         (Opts.ObjCRuntime.getKind() == ObjCRuntime::FragileMacOSX);
1277   }
1278 
1279   if (Args.hasArg(OPT_fgnu89_inline))
1280     Opts.GNUInline = 1;
1281 
1282   if (Args.hasArg(OPT_fapple_kext)) {
1283     if (!Opts.CPlusPlus)
1284       Diags.Report(diag::warn_c_kext);
1285     else
1286       Opts.AppleKext = 1;
1287   }
1288 
1289   if (Args.hasArg(OPT_print_ivar_layout))
1290     Opts.ObjCGCBitmapPrint = 1;
1291   if (Args.hasArg(OPT_fno_constant_cfstrings))
1292     Opts.NoConstantCFStrings = 1;
1293 
1294   if (Args.hasArg(OPT_faltivec))
1295     Opts.AltiVec = 1;
1296 
1297   if (Args.hasArg(OPT_pthread))
1298     Opts.POSIXThreads = 1;
1299 
1300   // The value-visibility mode defaults to "default".
1301   if (Arg *visOpt = Args.getLastArg(OPT_fvisibility)) {
1302     Opts.setValueVisibilityMode(parseVisibility(visOpt, Args, Diags));
1303   } else {
1304     Opts.setValueVisibilityMode(DefaultVisibility);
1305   }
1306 
1307   // The type-visibility mode defaults to the value-visibility mode.
1308   if (Arg *typeVisOpt = Args.getLastArg(OPT_ftype_visibility)) {
1309     Opts.setTypeVisibilityMode(parseVisibility(typeVisOpt, Args, Diags));
1310   } else {
1311     Opts.setTypeVisibilityMode(Opts.getValueVisibilityMode());
1312   }
1313 
1314   if (Args.hasArg(OPT_fvisibility_inlines_hidden))
1315     Opts.InlineVisibilityHidden = 1;
1316 
1317   if (Args.hasArg(OPT_ftrapv)) {
1318     Opts.setSignedOverflowBehavior(LangOptions::SOB_Trapping);
1319     // Set the handler, if one is specified.
1320     Opts.OverflowHandler =
1321         Args.getLastArgValue(OPT_ftrapv_handler);
1322   }
1323   else if (Args.hasArg(OPT_fwrapv))
1324     Opts.setSignedOverflowBehavior(LangOptions::SOB_Defined);
1325 
1326   if (Args.hasArg(OPT_trigraphs))
1327     Opts.Trigraphs = 1;
1328 
1329   Opts.DollarIdents = Args.hasFlag(OPT_fdollars_in_identifiers,
1330                                    OPT_fno_dollars_in_identifiers,
1331                                    Opts.DollarIdents);
1332   Opts.PascalStrings = Args.hasArg(OPT_fpascal_strings);
1333   Opts.MSVCCompat = Args.hasArg(OPT_fms_compatibility);
1334   Opts.MicrosoftExt = Opts.MSVCCompat || Args.hasArg(OPT_fms_extensions);
1335   Opts.AsmBlocks = Args.hasArg(OPT_fasm_blocks) || Opts.MicrosoftExt;
1336   Opts.MSCVersion = getLastArgIntValue(Args, OPT_fmsc_version, 0, Diags);
1337   Opts.VtorDispMode = getLastArgIntValue(Args, OPT_vtordisp_mode_EQ, 1, Diags);
1338   Opts.Borland = Args.hasArg(OPT_fborland_extensions);
1339   Opts.WritableStrings = Args.hasArg(OPT_fwritable_strings);
1340   Opts.ConstStrings = Args.hasFlag(OPT_fconst_strings, OPT_fno_const_strings,
1341                                    Opts.ConstStrings);
1342   if (Args.hasArg(OPT_fno_lax_vector_conversions))
1343     Opts.LaxVectorConversions = 0;
1344   if (Args.hasArg(OPT_fno_threadsafe_statics))
1345     Opts.ThreadsafeStatics = 0;
1346   Opts.Exceptions = Args.hasArg(OPT_fexceptions);
1347   Opts.ObjCExceptions = Args.hasArg(OPT_fobjc_exceptions);
1348   Opts.CXXExceptions = Args.hasArg(OPT_fcxx_exceptions);
1349   Opts.SjLjExceptions = Args.hasArg(OPT_fsjlj_exceptions);
1350   Opts.TraditionalCPP = Args.hasArg(OPT_traditional_cpp);
1351 
1352   Opts.RTTI = !Args.hasArg(OPT_fno_rtti);
1353   Opts.Blocks = Args.hasArg(OPT_fblocks);
1354   Opts.BlocksRuntimeOptional = Args.hasArg(OPT_fblocks_runtime_optional);
1355   Opts.Modules = Args.hasArg(OPT_fmodules);
1356   Opts.ModulesStrictDeclUse = Args.hasArg(OPT_fmodules_strict_decluse);
1357   Opts.ModulesDeclUse =
1358       Args.hasArg(OPT_fmodules_decluse) || Opts.ModulesStrictDeclUse;
1359   Opts.ModulesSearchAll = Opts.Modules &&
1360     !Args.hasArg(OPT_fno_modules_search_all) &&
1361     Args.hasArg(OPT_fmodules_search_all);
1362   Opts.CharIsSigned = Opts.OpenCL || !Args.hasArg(OPT_fno_signed_char);
1363   Opts.WChar = Opts.CPlusPlus && !Args.hasArg(OPT_fno_wchar);
1364   Opts.ShortWChar = Args.hasFlag(OPT_fshort_wchar, OPT_fno_short_wchar, false);
1365   Opts.ShortEnums = Args.hasArg(OPT_fshort_enums);
1366   Opts.Freestanding = Args.hasArg(OPT_ffreestanding);
1367   Opts.NoBuiltin = Args.hasArg(OPT_fno_builtin) || Opts.Freestanding;
1368   Opts.NoMathBuiltin = Args.hasArg(OPT_fno_math_builtin);
1369   Opts.AssumeSaneOperatorNew = !Args.hasArg(OPT_fno_assume_sane_operator_new);
1370   Opts.SizedDeallocation |= Args.hasArg(OPT_fsized_deallocation);
1371   Opts.HeinousExtensions = Args.hasArg(OPT_fheinous_gnu_extensions);
1372   Opts.AccessControl = !Args.hasArg(OPT_fno_access_control);
1373   Opts.ElideConstructors = !Args.hasArg(OPT_fno_elide_constructors);
1374   Opts.MathErrno = !Opts.OpenCL && Args.hasArg(OPT_fmath_errno);
1375   Opts.InstantiationDepth =
1376       getLastArgIntValue(Args, OPT_ftemplate_depth, 256, Diags);
1377   Opts.ArrowDepth =
1378       getLastArgIntValue(Args, OPT_foperator_arrow_depth, 256, Diags);
1379   Opts.ConstexprCallDepth =
1380       getLastArgIntValue(Args, OPT_fconstexpr_depth, 512, Diags);
1381   Opts.ConstexprStepLimit =
1382       getLastArgIntValue(Args, OPT_fconstexpr_steps, 1048576, Diags);
1383   Opts.BracketDepth = getLastArgIntValue(Args, OPT_fbracket_depth, 256, Diags);
1384   Opts.DelayedTemplateParsing = Args.hasArg(OPT_fdelayed_template_parsing);
1385   Opts.NumLargeByValueCopy =
1386       getLastArgIntValue(Args, OPT_Wlarge_by_value_copy_EQ, 0, Diags);
1387   Opts.MSBitfields = Args.hasArg(OPT_mms_bitfields);
1388   Opts.ObjCConstantStringClass =
1389     Args.getLastArgValue(OPT_fconstant_string_class);
1390   Opts.ObjCDefaultSynthProperties =
1391     !Args.hasArg(OPT_disable_objc_default_synthesize_properties);
1392   Opts.EncodeExtendedBlockSig =
1393     Args.hasArg(OPT_fencode_extended_block_signature);
1394   Opts.EmitAllDecls = Args.hasArg(OPT_femit_all_decls);
1395   Opts.PackStruct = getLastArgIntValue(Args, OPT_fpack_struct_EQ, 0, Diags);
1396   Opts.PICLevel = getLastArgIntValue(Args, OPT_pic_level, 0, Diags);
1397   Opts.PIELevel = getLastArgIntValue(Args, OPT_pie_level, 0, Diags);
1398   Opts.Static = Args.hasArg(OPT_static_define);
1399   Opts.DumpRecordLayoutsSimple = Args.hasArg(OPT_fdump_record_layouts_simple);
1400   Opts.DumpRecordLayouts = Opts.DumpRecordLayoutsSimple
1401                         || Args.hasArg(OPT_fdump_record_layouts);
1402   Opts.DumpVTableLayouts = Args.hasArg(OPT_fdump_vtable_layouts);
1403   Opts.SpellChecking = !Args.hasArg(OPT_fno_spell_checking);
1404   Opts.NoBitFieldTypeAlign = Args.hasArg(OPT_fno_bitfield_type_align);
1405   Opts.SinglePrecisionConstants = Args.hasArg(OPT_cl_single_precision_constant);
1406   Opts.FastRelaxedMath = Args.hasArg(OPT_cl_fast_relaxed_math);
1407   Opts.MRTD = Args.hasArg(OPT_mrtd);
1408   Opts.HexagonQdsp6Compat = Args.hasArg(OPT_mqdsp6_compat);
1409   Opts.FakeAddressSpaceMap = Args.hasArg(OPT_ffake_address_space_map);
1410   Opts.ParseUnknownAnytype = Args.hasArg(OPT_funknown_anytype);
1411   Opts.DebuggerSupport = Args.hasArg(OPT_fdebugger_support);
1412   Opts.DebuggerCastResultToId = Args.hasArg(OPT_fdebugger_cast_result_to_id);
1413   Opts.DebuggerObjCLiteral = Args.hasArg(OPT_fdebugger_objc_literal);
1414   Opts.ApplePragmaPack = Args.hasArg(OPT_fapple_pragma_pack);
1415   Opts.CurrentModule = Args.getLastArgValue(OPT_fmodule_name);
1416 
1417   if (Arg *A = Args.getLastArg(OPT_faddress_space_map_mangling_EQ)) {
1418     switch (llvm::StringSwitch<unsigned>(A->getValue())
1419       .Case("target", LangOptions::ASMM_Target)
1420       .Case("no", LangOptions::ASMM_Off)
1421       .Case("yes", LangOptions::ASMM_On)
1422       .Default(255)) {
1423     default:
1424       Diags.Report(diag::err_drv_invalid_value)
1425         << "-faddress-space-map-mangling=" << A->getValue();
1426       break;
1427     case LangOptions::ASMM_Target:
1428       Opts.setAddressSpaceMapMangling(LangOptions::ASMM_Target);
1429       break;
1430     case LangOptions::ASMM_On:
1431       Opts.setAddressSpaceMapMangling(LangOptions::ASMM_On);
1432       break;
1433     case LangOptions::ASMM_Off:
1434       Opts.setAddressSpaceMapMangling(LangOptions::ASMM_Off);
1435       break;
1436     }
1437   }
1438 
1439   if (Arg *A = Args.getLastArg(OPT_fms_memptr_rep_EQ)) {
1440     LangOptions::PragmaMSPointersToMembersKind InheritanceModel =
1441         llvm::StringSwitch<LangOptions::PragmaMSPointersToMembersKind>(
1442             A->getValue())
1443             .Case("single",
1444                   LangOptions::PPTMK_FullGeneralitySingleInheritance)
1445             .Case("multiple",
1446                   LangOptions::PPTMK_FullGeneralityMultipleInheritance)
1447             .Case("virtual",
1448                   LangOptions::PPTMK_FullGeneralityVirtualInheritance)
1449             .Default(LangOptions::PPTMK_BestCase);
1450     if (InheritanceModel == LangOptions::PPTMK_BestCase)
1451       Diags.Report(diag::err_drv_invalid_value)
1452           << "-fms-memptr-rep=" << A->getValue();
1453 
1454     Opts.setMSPointerToMemberRepresentationMethod(InheritanceModel);
1455   }
1456 
1457   // Check if -fopenmp= is specified.
1458   if (const Arg *A = Args.getLastArg(options::OPT_fopenmp_EQ)) {
1459     Opts.OpenMP = llvm::StringSwitch<bool>(A->getValue())
1460         .Case("libiomp5", true)
1461         .Default(false);
1462   }
1463 
1464   // Record whether the __DEPRECATED define was requested.
1465   Opts.Deprecated = Args.hasFlag(OPT_fdeprecated_macro,
1466                                  OPT_fno_deprecated_macro,
1467                                  Opts.Deprecated);
1468 
1469   // FIXME: Eliminate this dependency.
1470   unsigned Opt = getOptimizationLevel(Args, IK, Diags),
1471        OptSize = getOptimizationLevelSize(Args);
1472   Opts.Optimize = Opt != 0;
1473   Opts.OptimizeSize = OptSize != 0;
1474 
1475   // This is the __NO_INLINE__ define, which just depends on things like the
1476   // optimization level and -fno-inline, not actually whether the backend has
1477   // inlining enabled.
1478   Opts.NoInlineDefine = !Opt || Args.hasArg(OPT_fno_inline);
1479 
1480   Opts.FastMath = Args.hasArg(OPT_ffast_math);
1481   Opts.FiniteMathOnly = Args.hasArg(OPT_ffinite_math_only);
1482 
1483   Opts.RetainCommentsFromSystemHeaders =
1484       Args.hasArg(OPT_fretain_comments_from_system_headers);
1485 
1486   unsigned SSP = getLastArgIntValue(Args, OPT_stack_protector, 0, Diags);
1487   switch (SSP) {
1488   default:
1489     Diags.Report(diag::err_drv_invalid_value)
1490       << Args.getLastArg(OPT_stack_protector)->getAsString(Args) << SSP;
1491     break;
1492   case 0: Opts.setStackProtector(LangOptions::SSPOff); break;
1493   case 1: Opts.setStackProtector(LangOptions::SSPOn);  break;
1494   case 2: Opts.setStackProtector(LangOptions::SSPStrong); break;
1495   case 3: Opts.setStackProtector(LangOptions::SSPReq); break;
1496   }
1497 
1498   // Parse -fsanitize= arguments.
1499   std::vector<std::string> Sanitizers = Args.getAllArgValues(OPT_fsanitize_EQ);
1500   for (unsigned I = 0, N = Sanitizers.size(); I != N; ++I) {
1501     // Since the Opts.Sanitize* values are bitfields, it's a little tricky to
1502     // efficiently map string values to them. Perform the mapping indirectly:
1503     // convert strings to enumerated values, then switch over the enum to set
1504     // the right bitfield value.
1505     enum Sanitizer {
1506 #define SANITIZER(NAME, ID) \
1507       ID,
1508 #include "clang/Basic/Sanitizers.def"
1509       Unknown
1510     };
1511     switch (llvm::StringSwitch<unsigned>(Sanitizers[I])
1512 #define SANITIZER(NAME, ID) \
1513               .Case(NAME, ID)
1514 #include "clang/Basic/Sanitizers.def"
1515               .Default(Unknown)) {
1516 #define SANITIZER(NAME, ID) \
1517     case ID: \
1518       Opts.Sanitize.ID = true; \
1519       break;
1520 #include "clang/Basic/Sanitizers.def"
1521 
1522     case Unknown:
1523       Diags.Report(diag::err_drv_invalid_value)
1524         << "-fsanitize=" << Sanitizers[I];
1525       break;
1526     }
1527   }
1528 }
1529 
1530 static void ParsePreprocessorArgs(PreprocessorOptions &Opts, ArgList &Args,
1531                                   FileManager &FileMgr,
1532                                   DiagnosticsEngine &Diags) {
1533   using namespace options;
1534   Opts.ImplicitPCHInclude = Args.getLastArgValue(OPT_include_pch);
1535   Opts.ImplicitPTHInclude = Args.getLastArgValue(OPT_include_pth);
1536   if (const Arg *A = Args.getLastArg(OPT_token_cache))
1537       Opts.TokenCache = A->getValue();
1538   else
1539     Opts.TokenCache = Opts.ImplicitPTHInclude;
1540   Opts.UsePredefines = !Args.hasArg(OPT_undef);
1541   Opts.DetailedRecord = Args.hasArg(OPT_detailed_preprocessing_record);
1542   Opts.DisablePCHValidation = Args.hasArg(OPT_fno_validate_pch);
1543 
1544   Opts.DumpDeserializedPCHDecls = Args.hasArg(OPT_dump_deserialized_pch_decls);
1545   for (arg_iterator it = Args.filtered_begin(OPT_error_on_deserialized_pch_decl),
1546          ie = Args.filtered_end(); it != ie; ++it) {
1547     const Arg *A = *it;
1548     Opts.DeserializedPCHDeclsToErrorOn.insert(A->getValue());
1549   }
1550 
1551   if (const Arg *A = Args.getLastArg(OPT_preamble_bytes_EQ)) {
1552     StringRef Value(A->getValue());
1553     size_t Comma = Value.find(',');
1554     unsigned Bytes = 0;
1555     unsigned EndOfLine = 0;
1556 
1557     if (Comma == StringRef::npos ||
1558         Value.substr(0, Comma).getAsInteger(10, Bytes) ||
1559         Value.substr(Comma + 1).getAsInteger(10, EndOfLine))
1560       Diags.Report(diag::err_drv_preamble_format);
1561     else {
1562       Opts.PrecompiledPreambleBytes.first = Bytes;
1563       Opts.PrecompiledPreambleBytes.second = (EndOfLine != 0);
1564     }
1565   }
1566 
1567   // Add macros from the command line.
1568   for (arg_iterator it = Args.filtered_begin(OPT_D, OPT_U),
1569          ie = Args.filtered_end(); it != ie; ++it) {
1570     if ((*it)->getOption().matches(OPT_D))
1571       Opts.addMacroDef((*it)->getValue());
1572     else
1573       Opts.addMacroUndef((*it)->getValue());
1574   }
1575 
1576   Opts.MacroIncludes = Args.getAllArgValues(OPT_imacros);
1577 
1578   // Add the ordered list of -includes.
1579   for (arg_iterator it = Args.filtered_begin(OPT_include),
1580          ie = Args.filtered_end(); it != ie; ++it) {
1581     const Arg *A = *it;
1582     Opts.Includes.push_back(A->getValue());
1583   }
1584 
1585   for (arg_iterator it = Args.filtered_begin(OPT_chain_include),
1586          ie = Args.filtered_end(); it != ie; ++it) {
1587     const Arg *A = *it;
1588     Opts.ChainedIncludes.push_back(A->getValue());
1589   }
1590 
1591   // Include 'altivec.h' if -faltivec option present
1592   if (Args.hasArg(OPT_faltivec))
1593     Opts.Includes.push_back("altivec.h");
1594 
1595   for (arg_iterator it = Args.filtered_begin(OPT_remap_file),
1596          ie = Args.filtered_end(); it != ie; ++it) {
1597     const Arg *A = *it;
1598     std::pair<StringRef,StringRef> Split =
1599       StringRef(A->getValue()).split(';');
1600 
1601     if (Split.second.empty()) {
1602       Diags.Report(diag::err_drv_invalid_remap_file) << A->getAsString(Args);
1603       continue;
1604     }
1605 
1606     Opts.addRemappedFile(Split.first, Split.second);
1607   }
1608 
1609   if (Arg *A = Args.getLastArg(OPT_fobjc_arc_cxxlib_EQ)) {
1610     StringRef Name = A->getValue();
1611     unsigned Library = llvm::StringSwitch<unsigned>(Name)
1612       .Case("libc++", ARCXX_libcxx)
1613       .Case("libstdc++", ARCXX_libstdcxx)
1614       .Case("none", ARCXX_nolib)
1615       .Default(~0U);
1616     if (Library == ~0U)
1617       Diags.Report(diag::err_drv_invalid_value) << A->getAsString(Args) << Name;
1618     else
1619       Opts.ObjCXXARCStandardLibrary = (ObjCXXARCStandardLibraryKind)Library;
1620   }
1621 }
1622 
1623 static void ParsePreprocessorOutputArgs(PreprocessorOutputOptions &Opts,
1624                                         ArgList &Args,
1625                                         frontend::ActionKind Action) {
1626   using namespace options;
1627 
1628   switch (Action) {
1629   case frontend::ASTDeclList:
1630   case frontend::ASTDump:
1631   case frontend::ASTPrint:
1632   case frontend::ASTView:
1633   case frontend::EmitAssembly:
1634   case frontend::EmitBC:
1635   case frontend::EmitHTML:
1636   case frontend::EmitLLVM:
1637   case frontend::EmitLLVMOnly:
1638   case frontend::EmitCodeGenOnly:
1639   case frontend::EmitObj:
1640   case frontend::FixIt:
1641   case frontend::GenerateModule:
1642   case frontend::GeneratePCH:
1643   case frontend::GeneratePTH:
1644   case frontend::ParseSyntaxOnly:
1645   case frontend::ModuleFileInfo:
1646   case frontend::VerifyPCH:
1647   case frontend::PluginAction:
1648   case frontend::PrintDeclContext:
1649   case frontend::RewriteObjC:
1650   case frontend::RewriteTest:
1651   case frontend::RunAnalysis:
1652   case frontend::MigrateSource:
1653     Opts.ShowCPP = 0;
1654     break;
1655 
1656   case frontend::DumpRawTokens:
1657   case frontend::DumpTokens:
1658   case frontend::InitOnly:
1659   case frontend::PrintPreamble:
1660   case frontend::PrintPreprocessedInput:
1661   case frontend::RewriteMacros:
1662   case frontend::RunPreprocessorOnly:
1663     Opts.ShowCPP = !Args.hasArg(OPT_dM);
1664     break;
1665   }
1666 
1667   Opts.ShowComments = Args.hasArg(OPT_C);
1668   Opts.ShowLineMarkers = !Args.hasArg(OPT_P);
1669   Opts.ShowMacroComments = Args.hasArg(OPT_CC);
1670   Opts.ShowMacros = Args.hasArg(OPT_dM) || Args.hasArg(OPT_dD);
1671   Opts.RewriteIncludes = Args.hasArg(OPT_frewrite_includes);
1672 }
1673 
1674 static void ParseTargetArgs(TargetOptions &Opts, ArgList &Args) {
1675   using namespace options;
1676   Opts.ABI = Args.getLastArgValue(OPT_target_abi);
1677   Opts.CPU = Args.getLastArgValue(OPT_target_cpu);
1678   Opts.FPMath = Args.getLastArgValue(OPT_mfpmath);
1679   Opts.FeaturesAsWritten = Args.getAllArgValues(OPT_target_feature);
1680   Opts.LinkerVersion = Args.getLastArgValue(OPT_target_linker_version);
1681   Opts.Triple = llvm::Triple::normalize(Args.getLastArgValue(OPT_triple));
1682 
1683   // Use the default target triple if unspecified.
1684   if (Opts.Triple.empty())
1685     Opts.Triple = llvm::sys::getDefaultTargetTriple();
1686 }
1687 
1688 bool CompilerInvocation::CreateFromArgs(CompilerInvocation &Res,
1689                                         const char *const *ArgBegin,
1690                                         const char *const *ArgEnd,
1691                                         DiagnosticsEngine &Diags) {
1692   bool Success = true;
1693 
1694   // Parse the arguments.
1695   std::unique_ptr<OptTable> Opts(createDriverOptTable());
1696   const unsigned IncludedFlagsBitmask = options::CC1Option;
1697   unsigned MissingArgIndex, MissingArgCount;
1698   std::unique_ptr<InputArgList> Args(
1699       Opts->ParseArgs(ArgBegin, ArgEnd, MissingArgIndex, MissingArgCount,
1700                       IncludedFlagsBitmask));
1701 
1702   // Check for missing argument error.
1703   if (MissingArgCount) {
1704     Diags.Report(diag::err_drv_missing_argument)
1705       << Args->getArgString(MissingArgIndex) << MissingArgCount;
1706     Success = false;
1707   }
1708 
1709   // Issue errors on unknown arguments.
1710   for (arg_iterator it = Args->filtered_begin(OPT_UNKNOWN),
1711          ie = Args->filtered_end(); it != ie; ++it) {
1712     Diags.Report(diag::err_drv_unknown_argument) << (*it)->getAsString(*Args);
1713     Success = false;
1714   }
1715 
1716   Success = ParseAnalyzerArgs(*Res.getAnalyzerOpts(), *Args, Diags) && Success;
1717   Success = ParseMigratorArgs(Res.getMigratorOpts(), *Args) && Success;
1718   ParseDependencyOutputArgs(Res.getDependencyOutputOpts(), *Args);
1719   Success = ParseDiagnosticArgs(Res.getDiagnosticOpts(), *Args, &Diags)
1720             && Success;
1721   ParseCommentArgs(Res.getLangOpts()->CommentOpts, *Args);
1722   ParseFileSystemArgs(Res.getFileSystemOpts(), *Args);
1723   // FIXME: We shouldn't have to pass the DashX option around here
1724   InputKind DashX = ParseFrontendArgs(Res.getFrontendOpts(), *Args, Diags);
1725   ParseTargetArgs(Res.getTargetOpts(), *Args);
1726   Success = ParseCodeGenArgs(Res.getCodeGenOpts(), *Args, DashX, Diags,
1727                              Res.getTargetOpts()) && Success;
1728   ParseHeaderSearchArgs(Res.getHeaderSearchOpts(), *Args);
1729   if (DashX != IK_AST && DashX != IK_LLVM_IR) {
1730     ParseLangArgs(*Res.getLangOpts(), *Args, DashX, Diags);
1731     if (Res.getFrontendOpts().ProgramAction == frontend::RewriteObjC)
1732       Res.getLangOpts()->ObjCExceptions = 1;
1733   }
1734   // FIXME: ParsePreprocessorArgs uses the FileManager to read the contents of
1735   // PCH file and find the original header name. Remove the need to do that in
1736   // ParsePreprocessorArgs and remove the FileManager
1737   // parameters from the function and the "FileManager.h" #include.
1738   FileManager FileMgr(Res.getFileSystemOpts());
1739   ParsePreprocessorArgs(Res.getPreprocessorOpts(), *Args, FileMgr, Diags);
1740   ParsePreprocessorOutputArgs(Res.getPreprocessorOutputOpts(), *Args,
1741                               Res.getFrontendOpts().ProgramAction);
1742   return Success;
1743 }
1744 
1745 namespace {
1746 
1747   class ModuleSignature {
1748     SmallVector<uint64_t, 16> Data;
1749     unsigned CurBit;
1750     uint64_t CurValue;
1751 
1752   public:
1753     ModuleSignature() : CurBit(0), CurValue(0) { }
1754 
1755     void add(uint64_t Value, unsigned Bits);
1756     void add(StringRef Value);
1757     void flush();
1758 
1759     llvm::APInt getAsInteger() const;
1760   };
1761 }
1762 
1763 void ModuleSignature::add(uint64_t Value, unsigned int NumBits) {
1764   CurValue |= Value << CurBit;
1765   if (CurBit + NumBits < 64) {
1766     CurBit += NumBits;
1767     return;
1768   }
1769 
1770   // Add the current word.
1771   Data.push_back(CurValue);
1772 
1773   if (CurBit)
1774     CurValue = Value >> (64-CurBit);
1775   else
1776     CurValue = 0;
1777   CurBit = (CurBit+NumBits) & 63;
1778 }
1779 
1780 void ModuleSignature::flush() {
1781   if (CurBit == 0)
1782     return;
1783 
1784   Data.push_back(CurValue);
1785   CurBit = 0;
1786   CurValue = 0;
1787 }
1788 
1789 void ModuleSignature::add(StringRef Value) {
1790   for (StringRef::iterator I = Value.begin(), IEnd = Value.end(); I != IEnd;++I)
1791     add(*I, 8);
1792 }
1793 
1794 llvm::APInt ModuleSignature::getAsInteger() const {
1795   return llvm::APInt(Data.size() * 64, Data);
1796 }
1797 
1798 std::string CompilerInvocation::getModuleHash() const {
1799   // Note: For QoI reasons, the things we use as a hash here should all be
1800   // dumped via the -module-info flag.
1801   using llvm::hash_code;
1802   using llvm::hash_value;
1803   using llvm::hash_combine;
1804 
1805   // Start the signature with the compiler version.
1806   // FIXME: We'd rather use something more cryptographically sound than
1807   // CityHash, but this will do for now.
1808   hash_code code = hash_value(getClangFullRepositoryVersion());
1809 
1810   // Extend the signature with the language options
1811 #define LANGOPT(Name, Bits, Default, Description) \
1812    code = hash_combine(code, LangOpts->Name);
1813 #define ENUM_LANGOPT(Name, Type, Bits, Default, Description) \
1814   code = hash_combine(code, static_cast<unsigned>(LangOpts->get##Name()));
1815 #define BENIGN_LANGOPT(Name, Bits, Default, Description)
1816 #define BENIGN_ENUM_LANGOPT(Name, Type, Bits, Default, Description)
1817 #include "clang/Basic/LangOptions.def"
1818 
1819   // Extend the signature with the target options.
1820   code = hash_combine(code, TargetOpts->Triple, TargetOpts->CPU,
1821                       TargetOpts->ABI);
1822   for (unsigned i = 0, n = TargetOpts->FeaturesAsWritten.size(); i != n; ++i)
1823     code = hash_combine(code, TargetOpts->FeaturesAsWritten[i]);
1824 
1825   // Extend the signature with preprocessor options.
1826   const PreprocessorOptions &ppOpts = getPreprocessorOpts();
1827   const HeaderSearchOptions &hsOpts = getHeaderSearchOpts();
1828   code = hash_combine(code, ppOpts.UsePredefines, ppOpts.DetailedRecord);
1829 
1830   for (std::vector<std::pair<std::string, bool/*isUndef*/> >::const_iterator
1831             I = getPreprocessorOpts().Macros.begin(),
1832          IEnd = getPreprocessorOpts().Macros.end();
1833        I != IEnd; ++I) {
1834     // If we're supposed to ignore this macro for the purposes of modules,
1835     // don't put it into the hash.
1836     if (!hsOpts.ModulesIgnoreMacros.empty()) {
1837       // Check whether we're ignoring this macro.
1838       StringRef MacroDef = I->first;
1839       if (hsOpts.ModulesIgnoreMacros.count(MacroDef.split('=').first))
1840         continue;
1841     }
1842 
1843     code = hash_combine(code, I->first, I->second);
1844   }
1845 
1846   // Extend the signature with the sysroot.
1847   code = hash_combine(code, hsOpts.Sysroot, hsOpts.UseBuiltinIncludes,
1848                       hsOpts.UseStandardSystemIncludes,
1849                       hsOpts.UseStandardCXXIncludes,
1850                       hsOpts.UseLibcxx);
1851   code = hash_combine(code, hsOpts.ResourceDir);
1852 
1853   // Extend the signature with the user build path.
1854   code = hash_combine(code, hsOpts.ModuleUserBuildPath);
1855 
1856   // Darwin-specific hack: if we have a sysroot, use the contents and
1857   // modification time of
1858   //   $sysroot/System/Library/CoreServices/SystemVersion.plist
1859   // as part of the module hash.
1860   if (!hsOpts.Sysroot.empty()) {
1861     std::unique_ptr<llvm::MemoryBuffer> buffer;
1862     SmallString<128> systemVersionFile;
1863     systemVersionFile += hsOpts.Sysroot;
1864     llvm::sys::path::append(systemVersionFile, "System");
1865     llvm::sys::path::append(systemVersionFile, "Library");
1866     llvm::sys::path::append(systemVersionFile, "CoreServices");
1867     llvm::sys::path::append(systemVersionFile, "SystemVersion.plist");
1868     if (!llvm::MemoryBuffer::getFile(systemVersionFile.str(), buffer)) {
1869       code = hash_combine(code, buffer.get()->getBuffer());
1870 
1871       struct stat statBuf;
1872       if (stat(systemVersionFile.c_str(), &statBuf) == 0)
1873         code = hash_combine(code, statBuf.st_mtime);
1874     }
1875   }
1876 
1877   return llvm::APInt(64, code).toString(36, /*Signed=*/false);
1878 }
1879 
1880 namespace clang {
1881 
1882 template<typename IntTy>
1883 static IntTy getLastArgIntValueImpl(const ArgList &Args, OptSpecifier Id,
1884                                     IntTy Default,
1885                                     DiagnosticsEngine *Diags) {
1886   IntTy Res = Default;
1887   if (Arg *A = Args.getLastArg(Id)) {
1888     if (StringRef(A->getValue()).getAsInteger(10, Res)) {
1889       if (Diags)
1890         Diags->Report(diag::err_drv_invalid_int_value) << A->getAsString(Args)
1891                                                        << A->getValue();
1892     }
1893   }
1894   return Res;
1895 }
1896 
1897 
1898 // Declared in clang/Frontend/Utils.h.
1899 int getLastArgIntValue(const ArgList &Args, OptSpecifier Id, int Default,
1900                        DiagnosticsEngine *Diags) {
1901   return getLastArgIntValueImpl<int>(Args, Id, Default, Diags);
1902 }
1903 
1904 uint64_t getLastArgUInt64Value(const ArgList &Args, OptSpecifier Id,
1905                                uint64_t Default,
1906                                DiagnosticsEngine *Diags) {
1907   return getLastArgIntValueImpl<uint64_t>(Args, Id, Default, Diags);
1908 }
1909 
1910 void BuryPointer(const void *Ptr) {
1911   // This function may be called only a small fixed amount of times per each
1912   // invocation, otherwise we do actually have a leak which we want to report.
1913   // If this function is called more than kGraveYardMaxSize times, the pointers
1914   // will not be properly buried and a leak detector will report a leak, which
1915   // is what we want in such case.
1916   static const size_t kGraveYardMaxSize = 16;
1917   LLVM_ATTRIBUTE_UNUSED static const void *GraveYard[kGraveYardMaxSize];
1918   static std::atomic<unsigned> GraveYardSize;
1919   unsigned Idx = GraveYardSize++;
1920   if (Idx >= kGraveYardMaxSize)
1921     return;
1922   GraveYard[Idx] = Ptr;
1923 }
1924 
1925 IntrusiveRefCntPtr<vfs::FileSystem>
1926 createVFSFromCompilerInvocation(const CompilerInvocation &CI,
1927                                 DiagnosticsEngine &Diags) {
1928   if (CI.getHeaderSearchOpts().VFSOverlayFiles.empty())
1929     return vfs::getRealFileSystem();
1930 
1931   IntrusiveRefCntPtr<vfs::OverlayFileSystem>
1932     Overlay(new vfs::OverlayFileSystem(vfs::getRealFileSystem()));
1933   // earlier vfs files are on the bottom
1934   for (const std::string &File : CI.getHeaderSearchOpts().VFSOverlayFiles) {
1935     std::unique_ptr<llvm::MemoryBuffer> Buffer;
1936     if (llvm::errc::success != llvm::MemoryBuffer::getFile(File, Buffer)) {
1937       Diags.Report(diag::err_missing_vfs_overlay_file) << File;
1938       return IntrusiveRefCntPtr<vfs::FileSystem>();
1939     }
1940 
1941     IntrusiveRefCntPtr<vfs::FileSystem> FS =
1942         vfs::getVFSFromYAML(Buffer.release(), /*DiagHandler*/0);
1943     if (!FS.getPtr()) {
1944       Diags.Report(diag::err_invalid_vfs_overlay) << File;
1945       return IntrusiveRefCntPtr<vfs::FileSystem>();
1946     }
1947     Overlay->pushOverlay(FS);
1948   }
1949   return Overlay;
1950 }
1951 } // end namespace clang
1952