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-rw-r--r--ELF/Driver.cpp463
1 files changed, 358 insertions, 105 deletions
diff --git a/ELF/Driver.cpp b/ELF/Driver.cpp
index f00d97851e4a..c6ca2639236f 100644
--- a/ELF/Driver.cpp
+++ b/ELF/Driver.cpp
@@ -10,119 +10,218 @@
#include "Driver.h"
#include "Config.h"
#include "Error.h"
+#include "ICF.h"
#include "InputFiles.h"
+#include "InputSection.h"
+#include "LinkerScript.h"
+#include "Strings.h"
+#include "SymbolListFile.h"
#include "SymbolTable.h"
#include "Target.h"
#include "Writer.h"
-#include "llvm/ADT/STLExtras.h"
+#include "lld/Driver/Driver.h"
#include "llvm/ADT/StringExtras.h"
+#include "llvm/ADT/StringSwitch.h"
+#include "llvm/Support/TargetSelect.h"
#include "llvm/Support/raw_ostream.h"
+#include <cstdlib>
#include <utility>
using namespace llvm;
using namespace llvm::ELF;
using namespace llvm::object;
+using namespace llvm::sys;
using namespace lld;
-using namespace lld::elf2;
+using namespace lld::elf;
-Configuration *elf2::Config;
-LinkerDriver *elf2::Driver;
+Configuration *elf::Config;
+LinkerDriver *elf::Driver;
+
+bool elf::link(ArrayRef<const char *> Args, raw_ostream &Error) {
+ HasError = false;
+ ErrorOS = &Error;
-void elf2::link(ArrayRef<const char *> Args) {
Configuration C;
LinkerDriver D;
+ ScriptConfiguration SC;
Config = &C;
Driver = &D;
- Driver->main(Args.slice(1));
+ ScriptConfig = &SC;
+
+ Driver->main(Args);
+ return !HasError;
}
+// Parses a linker -m option.
static std::pair<ELFKind, uint16_t> parseEmulation(StringRef S) {
- if (S == "elf32btsmip")
- return {ELF32BEKind, EM_MIPS};
- if (S == "elf32ltsmip")
- return {ELF32LEKind, EM_MIPS};
- if (S == "elf32ppc" || S == "elf32ppc_fbsd")
- return {ELF32BEKind, EM_PPC};
- if (S == "elf64ppc" || S == "elf64ppc_fbsd")
- return {ELF64BEKind, EM_PPC64};
- if (S == "elf_i386")
- return {ELF32LEKind, EM_386};
- if (S == "elf_x86_64")
- return {ELF64LEKind, EM_X86_64};
- if (S == "aarch64linux")
- return {ELF64LEKind, EM_AARCH64};
- if (S == "i386pe" || S == "i386pep" || S == "thumb2pe")
- error("Windows targets are not supported on the ELF frontend: " + S);
- error("Unknown emulation: " + S);
+ if (S.endswith("_fbsd"))
+ S = S.drop_back(5);
+
+ std::pair<ELFKind, uint16_t> Ret =
+ StringSwitch<std::pair<ELFKind, uint16_t>>(S)
+ .Case("aarch64linux", {ELF64LEKind, EM_AARCH64})
+ .Case("armelf_linux_eabi", {ELF32LEKind, EM_ARM})
+ .Case("elf32_x86_64", {ELF32LEKind, EM_X86_64})
+ .Case("elf32btsmip", {ELF32BEKind, EM_MIPS})
+ .Case("elf32ltsmip", {ELF32LEKind, EM_MIPS})
+ .Case("elf32ppc", {ELF32BEKind, EM_PPC})
+ .Case("elf64btsmip", {ELF64BEKind, EM_MIPS})
+ .Case("elf64ltsmip", {ELF64LEKind, EM_MIPS})
+ .Case("elf64ppc", {ELF64BEKind, EM_PPC64})
+ .Case("elf_i386", {ELF32LEKind, EM_386})
+ .Case("elf_x86_64", {ELF64LEKind, EM_X86_64})
+ .Default({ELFNoneKind, EM_NONE});
+
+ if (Ret.first == ELFNoneKind) {
+ if (S == "i386pe" || S == "i386pep" || S == "thumb2pe")
+ error("Windows targets are not supported on the ELF frontend: " + S);
+ else
+ error("unknown emulation: " + S);
+ }
+ return Ret;
}
// Returns slices of MB by parsing MB as an archive file.
// Each slice consists of a member file in the archive.
-static std::vector<MemoryBufferRef> getArchiveMembers(MemoryBufferRef MB) {
- ErrorOr<std::unique_ptr<Archive>> FileOrErr = Archive::create(MB);
- error(FileOrErr, "Failed to parse archive");
- std::unique_ptr<Archive> File = std::move(*FileOrErr);
+std::vector<MemoryBufferRef>
+LinkerDriver::getArchiveMembers(MemoryBufferRef MB) {
+ std::unique_ptr<Archive> File =
+ check(Archive::create(MB), "failed to parse archive");
std::vector<MemoryBufferRef> V;
- for (const ErrorOr<Archive::Child> &C : File->children()) {
- error(C, "Could not get the child of the archive " + File->getFileName());
- ErrorOr<MemoryBufferRef> MbOrErr = C->getMemoryBufferRef();
- error(MbOrErr, "Could not get the buffer for a child of the archive " +
- File->getFileName());
- V.push_back(*MbOrErr);
+ Error Err;
+ for (const ErrorOr<Archive::Child> &COrErr : File->children(Err)) {
+ Archive::Child C = check(COrErr, "could not get the child of the archive " +
+ File->getFileName());
+ MemoryBufferRef MBRef =
+ check(C.getMemoryBufferRef(),
+ "could not get the buffer for a child of the archive " +
+ File->getFileName());
+ V.push_back(MBRef);
}
+ if (Err)
+ Error(Err);
+
+ // Take ownership of memory buffers created for members of thin archives.
+ for (std::unique_ptr<MemoryBuffer> &MB : File->takeThinBuffers())
+ OwningMBs.push_back(std::move(MB));
+
return V;
}
// Opens and parses a file. Path has to be resolved already.
// Newly created memory buffers are owned by this driver.
void LinkerDriver::addFile(StringRef Path) {
- using namespace llvm::sys::fs;
+ using namespace sys::fs;
if (Config->Verbose)
- llvm::outs() << Path << "\n";
- auto MBOrErr = MemoryBuffer::getFile(Path);
- error(MBOrErr, "cannot open " + Path);
- std::unique_ptr<MemoryBuffer> &MB = *MBOrErr;
- MemoryBufferRef MBRef = MB->getMemBufferRef();
- OwningMBs.push_back(std::move(MB)); // take MB ownership
+ outs() << Path << "\n";
+
+ Optional<MemoryBufferRef> Buffer = readFile(Path);
+ if (!Buffer.hasValue())
+ return;
+ MemoryBufferRef MBRef = *Buffer;
switch (identify_magic(MBRef.getBuffer())) {
case file_magic::unknown:
- readLinkerScript(&Alloc, MBRef);
+ readLinkerScript(MBRef);
return;
case file_magic::archive:
if (WholeArchive) {
for (MemoryBufferRef MB : getArchiveMembers(MBRef))
- Files.push_back(createObjectFile(MB));
+ Files.push_back(createObjectFile(MB, Path));
return;
}
Files.push_back(make_unique<ArchiveFile>(MBRef));
return;
case file_magic::elf_shared_object:
+ if (Config->Relocatable) {
+ error("attempted static link of dynamic object " + Path);
+ return;
+ }
Files.push_back(createSharedFile(MBRef));
return;
default:
- Files.push_back(createObjectFile(MBRef));
+ if (InLib)
+ Files.push_back(make_unique<LazyObjectFile>(MBRef));
+ else
+ Files.push_back(createObjectFile(MBRef));
+ }
+}
+
+Optional<MemoryBufferRef> LinkerDriver::readFile(StringRef Path) {
+ auto MBOrErr = MemoryBuffer::getFile(Path);
+ if (auto EC = MBOrErr.getError()) {
+ error(EC, "cannot open " + Path);
+ return None;
}
+ std::unique_ptr<MemoryBuffer> &MB = *MBOrErr;
+ MemoryBufferRef MBRef = MB->getMemBufferRef();
+ OwningMBs.push_back(std::move(MB)); // take MB ownership
+
+ if (Cpio)
+ Cpio->append(relativeToRoot(Path), MBRef.getBuffer());
+
+ return MBRef;
+}
+
+// Add a given library by searching it from input search paths.
+void LinkerDriver::addLibrary(StringRef Name) {
+ std::string Path = searchLibrary(Name);
+ if (Path.empty())
+ error("unable to find library -l" + Name);
+ else
+ addFile(Path);
+}
+
+// This function is called on startup. We need this for LTO since
+// LTO calls LLVM functions to compile bitcode files to native code.
+// Technically this can be delayed until we read bitcode files, but
+// we don't bother to do lazily because the initialization is fast.
+static void initLLVM(opt::InputArgList &Args) {
+ InitializeAllTargets();
+ InitializeAllTargetMCs();
+ InitializeAllAsmPrinters();
+ InitializeAllAsmParsers();
+
+ // This is a flag to discard all but GlobalValue names.
+ // We want to enable it by default because it saves memory.
+ // Disable it only when a developer option (-save-temps) is given.
+ Driver->Context.setDiscardValueNames(!Config->SaveTemps);
+ Driver->Context.enableDebugTypeODRUniquing();
+
+ // Parse and evaluate -mllvm options.
+ std::vector<const char *> V;
+ V.push_back("lld (LLVM option parsing)");
+ for (auto *Arg : Args.filtered(OPT_mllvm))
+ V.push_back(Arg->getValue());
+ cl::ParseCommandLineOptions(V.size(), V.data());
}
// Some command line options or some combinations of them are not allowed.
// This function checks for such errors.
static void checkOptions(opt::InputArgList &Args) {
- // Traditional linkers can generate re-linkable object files instead
- // of executables or DSOs. We don't support that since the feature
- // does not seem to provide more value than the static archiver.
- if (Args.hasArg(OPT_relocatable))
- error("-r option is not supported. Use 'ar' command instead.");
-
// The MIPS ABI as of 2016 does not support the GNU-style symbol lookup
// table which is a relatively new feature.
if (Config->EMachine == EM_MIPS && Config->GnuHash)
- error("The .gnu.hash section is not compatible with the MIPS target.");
+ error("the .gnu.hash section is not compatible with the MIPS target.");
if (Config->EMachine == EM_AMDGPU && !Config->Entry.empty())
error("-e option is not valid for AMDGPU.");
+
+ if (Config->Pie && Config->Shared)
+ error("-shared and -pie may not be used together");
+
+ if (Config->Relocatable) {
+ if (Config->Shared)
+ error("-r and -shared may not be used together");
+ if (Config->GcSections)
+ error("-r and --gc-sections may not be used together");
+ if (Config->ICF)
+ error("-r and --icf may not be used together");
+ if (Config->Pie)
+ error("-r and -pie may not be used together");
+ }
}
static StringRef
@@ -132,6 +231,22 @@ getString(opt::InputArgList &Args, unsigned Key, StringRef Default = "") {
return Default;
}
+static int getInteger(opt::InputArgList &Args, unsigned Key, int Default) {
+ int V = Default;
+ if (auto *Arg = Args.getLastArg(Key)) {
+ StringRef S = Arg->getValue();
+ if (S.getAsInteger(10, V))
+ error(Arg->getSpelling() + ": number expected, but got " + S);
+ }
+ return V;
+}
+
+static const char *getReproduceOption(opt::InputArgList &Args) {
+ if (auto *Arg = Args.getLastArg(OPT_reproduce))
+ return Arg->getValue();
+ return getenv("LLD_REPRODUCE");
+}
+
static bool hasZOption(opt::InputArgList &Args, StringRef Key) {
for (auto *Arg : Args.filtered(OPT_z))
if (Key == Arg->getValue())
@@ -140,12 +255,33 @@ static bool hasZOption(opt::InputArgList &Args, StringRef Key) {
}
void LinkerDriver::main(ArrayRef<const char *> ArgsArr) {
- initSymbols();
+ ELFOptTable Parser;
+ opt::InputArgList Args = Parser.parse(ArgsArr.slice(1));
+ if (Args.hasArg(OPT_help)) {
+ printHelp(ArgsArr[0]);
+ return;
+ }
+ if (Args.hasArg(OPT_version)) {
+ outs() << getVersionString();
+ return;
+ }
+
+ if (const char *Path = getReproduceOption(Args)) {
+ // Note that --reproduce is a debug option so you can ignore it
+ // if you are trying to understand the whole picture of the code.
+ Cpio.reset(CpioFile::create(Path));
+ if (Cpio) {
+ Cpio->append("response.txt", createResponseFile(Args));
+ Cpio->append("version.txt", getVersionString());
+ }
+ }
- opt::InputArgList Args = parseArgs(&Alloc, ArgsArr);
readConfigs(Args);
+ initLLVM(Args);
createFiles(Args);
checkOptions(Args);
+ if (HasError)
+ return;
switch (Config->EKind) {
case ELF32LEKind:
@@ -165,6 +301,25 @@ void LinkerDriver::main(ArrayRef<const char *> ArgsArr) {
}
}
+static UnresolvedPolicy getUnresolvedSymbolOption(opt::InputArgList &Args) {
+ if (Args.hasArg(OPT_noinhibit_exec))
+ return UnresolvedPolicy::Warn;
+ if (Args.hasArg(OPT_no_undefined) || hasZOption(Args, "defs"))
+ return UnresolvedPolicy::NoUndef;
+ if (Config->Relocatable)
+ return UnresolvedPolicy::Ignore;
+
+ if (auto *Arg = Args.getLastArg(OPT_unresolved_symbols)) {
+ StringRef S = Arg->getValue();
+ if (S == "ignore-all" || S == "ignore-in-object-files")
+ return UnresolvedPolicy::Ignore;
+ if (S == "ignore-in-shared-libs" || S == "report-all")
+ return UnresolvedPolicy::Error;
+ error("unknown --unresolved-symbols value: " + S);
+ }
+ return UnresolvedPolicy::Error;
+}
+
// Initializes Config members by the command line options.
void LinkerDriver::readConfigs(opt::InputArgList &Args) {
for (auto *Arg : Args.filtered(OPT_L))
@@ -185,38 +340,66 @@ void LinkerDriver::readConfigs(opt::InputArgList &Args) {
Config->AllowMultipleDefinition = Args.hasArg(OPT_allow_multiple_definition);
Config->Bsymbolic = Args.hasArg(OPT_Bsymbolic);
+ Config->BsymbolicFunctions = Args.hasArg(OPT_Bsymbolic_functions);
+ Config->Demangle = !Args.hasArg(OPT_no_demangle);
+ Config->DisableVerify = Args.hasArg(OPT_disable_verify);
Config->DiscardAll = Args.hasArg(OPT_discard_all);
Config->DiscardLocals = Args.hasArg(OPT_discard_locals);
Config->DiscardNone = Args.hasArg(OPT_discard_none);
+ Config->EhFrameHdr = Args.hasArg(OPT_eh_frame_hdr);
Config->EnableNewDtags = !Args.hasArg(OPT_disable_new_dtags);
Config->ExportDynamic = Args.hasArg(OPT_export_dynamic);
+ Config->FatalWarnings = Args.hasArg(OPT_fatal_warnings);
Config->GcSections = Args.hasArg(OPT_gc_sections);
- Config->NoInhibitExec = Args.hasArg(OPT_noinhibit_exec);
- Config->NoUndefined = Args.hasArg(OPT_no_undefined);
+ Config->ICF = Args.hasArg(OPT_icf);
+ Config->NoGnuUnique = Args.hasArg(OPT_no_gnu_unique);
+ Config->NoUndefinedVersion = Args.hasArg(OPT_no_undefined_version);
+ Config->Pie = Args.hasArg(OPT_pie);
Config->PrintGcSections = Args.hasArg(OPT_print_gc_sections);
+ Config->Relocatable = Args.hasArg(OPT_relocatable);
+ Config->SaveTemps = Args.hasArg(OPT_save_temps);
Config->Shared = Args.hasArg(OPT_shared);
Config->StripAll = Args.hasArg(OPT_strip_all);
+ Config->StripDebug = Args.hasArg(OPT_strip_debug);
+ Config->Threads = Args.hasArg(OPT_threads);
+ Config->Trace = Args.hasArg(OPT_trace);
Config->Verbose = Args.hasArg(OPT_verbose);
+ Config->WarnCommon = Args.hasArg(OPT_warn_common);
Config->DynamicLinker = getString(Args, OPT_dynamic_linker);
Config->Entry = getString(Args, OPT_entry);
Config->Fini = getString(Args, OPT_fini, "_fini");
Config->Init = getString(Args, OPT_init, "_init");
+ Config->LtoAAPipeline = getString(Args, OPT_lto_aa_pipeline);
+ Config->LtoNewPmPasses = getString(Args, OPT_lto_newpm_passes);
Config->OutputFile = getString(Args, OPT_o);
Config->SoName = getString(Args, OPT_soname);
Config->Sysroot = getString(Args, OPT_sysroot);
+ Config->Optimize = getInteger(Args, OPT_O, 1);
+ Config->LtoO = getInteger(Args, OPT_lto_O, 2);
+ if (Config->LtoO > 3)
+ error("invalid optimization level for LTO: " + getString(Args, OPT_lto_O));
+ Config->LtoJobs = getInteger(Args, OPT_lto_jobs, 1);
+ if (Config->LtoJobs == 0)
+ error("number of threads must be > 0");
+
+ Config->ZCombreloc = !hasZOption(Args, "nocombreloc");
Config->ZExecStack = hasZOption(Args, "execstack");
Config->ZNodelete = hasZOption(Args, "nodelete");
Config->ZNow = hasZOption(Args, "now");
Config->ZOrigin = hasZOption(Args, "origin");
Config->ZRelro = !hasZOption(Args, "norelro");
- if (auto *Arg = Args.getLastArg(OPT_O)) {
- StringRef Val = Arg->getValue();
- if (Val.getAsInteger(10, Config->Optimize))
- error("Invalid optimization level");
- }
+ if (Config->Relocatable)
+ Config->StripAll = false;
+
+ // --strip-all implies --strip-debug.
+ if (Config->StripAll)
+ Config->StripDebug = true;
+
+ // Config->Pic is true if we are generating position-independent code.
+ Config->Pic = Config->Pie || Config->Shared;
if (auto *Arg = Args.getLastArg(OPT_hash_style)) {
StringRef S = Arg->getValue();
@@ -226,19 +409,52 @@ void LinkerDriver::readConfigs(opt::InputArgList &Args) {
} else if (S == "both") {
Config->GnuHash = true;
} else if (S != "sysv")
- error("Unknown hash style: " + S);
+ error("unknown hash style: " + S);
+ }
+
+ // Parse --build-id or --build-id=<style>.
+ if (Args.hasArg(OPT_build_id))
+ Config->BuildId = BuildIdKind::Fnv1;
+ if (auto *Arg = Args.getLastArg(OPT_build_id_eq)) {
+ StringRef S = Arg->getValue();
+ if (S == "md5") {
+ Config->BuildId = BuildIdKind::Md5;
+ } else if (S == "sha1") {
+ Config->BuildId = BuildIdKind::Sha1;
+ } else if (S == "none") {
+ Config->BuildId = BuildIdKind::None;
+ } else if (S.startswith("0x")) {
+ Config->BuildId = BuildIdKind::Hexstring;
+ Config->BuildIdVector = parseHex(S.substr(2));
+ } else {
+ error("unknown --build-id style: " + S);
+ }
}
for (auto *Arg : Args.filtered(OPT_undefined))
Config->Undefined.push_back(Arg->getValue());
+
+ Config->UnresolvedSymbols = getUnresolvedSymbolOption(Args);
+
+ if (auto *Arg = Args.getLastArg(OPT_dynamic_list))
+ if (Optional<MemoryBufferRef> Buffer = readFile(Arg->getValue()))
+ parseDynamicList(*Buffer);
+
+ for (auto *Arg : Args.filtered(OPT_export_dynamic_symbol))
+ Config->DynamicList.push_back(Arg->getValue());
+
+ if (auto *Arg = Args.getLastArg(OPT_version_script))
+ if (Optional<MemoryBufferRef> Buffer = readFile(Arg->getValue()))
+ parseVersionScript(*Buffer);
}
void LinkerDriver::createFiles(opt::InputArgList &Args) {
for (auto *Arg : Args) {
switch (Arg->getOption().getID()) {
case OPT_l:
- addFile(searchLibrary(Arg->getValue()));
+ addLibrary(Arg->getValue());
break;
+ case OPT_alias_script_T:
case OPT_INPUT:
case OPT_script:
addFile(Arg->getValue());
@@ -261,75 +477,112 @@ void LinkerDriver::createFiles(opt::InputArgList &Args) {
case OPT_no_whole_archive:
WholeArchive = false;
break;
+ case OPT_start_lib:
+ InLib = true;
+ break;
+ case OPT_end_lib:
+ InLib = false;
+ break;
}
}
- if (Files.empty())
+ if (Files.empty() && !HasError)
error("no input files.");
+
+ // If -m <machine_type> was not given, infer it from object files.
+ if (Config->EKind == ELFNoneKind) {
+ for (std::unique_ptr<InputFile> &F : Files) {
+ if (F->EKind == ELFNoneKind)
+ continue;
+ Config->EKind = F->EKind;
+ Config->EMachine = F->EMachine;
+ break;
+ }
+ }
}
+// Do actual linking. Note that when this function is called,
+// all linker scripts have already been parsed.
template <class ELFT> void LinkerDriver::link(opt::InputArgList &Args) {
SymbolTable<ELFT> Symtab;
- Target.reset(createTarget());
-
- if (!Config->Shared) {
- // Add entry symbol.
- //
- // There is no entry symbol for AMDGPU binaries, so skip adding one to avoid
- // having and undefined symbol.
- if (Config->Entry.empty() && Config->EMachine != EM_AMDGPU)
- Config->Entry = (Config->EMachine == EM_MIPS) ? "__start" : "_start";
-
- // In the assembly for 32 bit x86 the _GLOBAL_OFFSET_TABLE_ symbol
- // is magical and is used to produce a R_386_GOTPC relocation.
- // The R_386_GOTPC relocation value doesn't actually depend on the
- // symbol value, so it could use an index of STN_UNDEF which, according
- // to the spec, means the symbol value is 0.
- // Unfortunately both gas and MC keep the _GLOBAL_OFFSET_TABLE_ symbol in
- // the object file.
- // The situation is even stranger on x86_64 where the assembly doesn't
- // need the magical symbol, but gas still puts _GLOBAL_OFFSET_TABLE_ as
- // an undefined symbol in the .o files.
- // Given that the symbol is effectively unused, we just create a dummy
- // hidden one to avoid the undefined symbol error.
- Symtab.addIgnored("_GLOBAL_OFFSET_TABLE_");
- }
+ elf::Symtab<ELFT>::X = &Symtab;
+
+ std::unique_ptr<TargetInfo> TI(createTarget());
+ Target = TI.get();
+ LinkerScript<ELFT> LS;
+ Script<ELFT>::X = &LS;
+
+ Config->Rela = ELFT::Is64Bits || Config->EMachine == EM_X86_64;
+ Config->Mips64EL =
+ (Config->EMachine == EM_MIPS && Config->EKind == ELF64LEKind);
+
+ // Add entry symbol. Note that AMDGPU binaries have no entry points.
+ if (Config->Entry.empty() && !Config->Shared && !Config->Relocatable &&
+ Config->EMachine != EM_AMDGPU)
+ Config->Entry = (Config->EMachine == EM_MIPS) ? "__start" : "_start";
+
+ // Default output filename is "a.out" by the Unix tradition.
+ if (Config->OutputFile.empty())
+ Config->OutputFile = "a.out";
+
+ // Handle --trace-symbol.
+ for (auto *Arg : Args.filtered(OPT_trace_symbol))
+ Symtab.trace(Arg->getValue());
+ // Set either EntryAddr (if S is a number) or EntrySym (otherwise).
if (!Config->Entry.empty()) {
- // Set either EntryAddr (if S is a number) or EntrySym (otherwise).
StringRef S = Config->Entry;
if (S.getAsInteger(0, Config->EntryAddr))
Config->EntrySym = Symtab.addUndefined(S);
}
- if (Config->EMachine == EM_MIPS) {
- // On MIPS O32 ABI, _gp_disp is a magic symbol designates offset between
- // start of function and gp pointer into GOT. Use 'strong' variant of
- // the addIgnored to prevent '_gp_disp' substitution.
- Config->MipsGpDisp = Symtab.addIgnoredStrong("_gp_disp");
-
- // Define _gp for MIPS. st_value of _gp symbol will be updated by Writer
- // so that it points to an absolute address which is relative to GOT.
- // See "Global Data Symbols" in Chapter 6 in the following document:
- // ftp://www.linux-mips.org/pub/linux/mips/doc/ABI/mipsabi.pdf
- Symtab.addAbsolute("_gp", ElfSym<ELFT>::MipsGp);
+ // Initialize Config->ImageBase.
+ if (auto *Arg = Args.getLastArg(OPT_image_base)) {
+ StringRef S = Arg->getValue();
+ if (S.getAsInteger(0, Config->ImageBase))
+ error(Arg->getSpelling() + ": number expected, but got " + S);
+ else if ((Config->ImageBase % Target->PageSize) != 0)
+ warning(Arg->getSpelling() + ": address isn't multiple of page size");
+ } else {
+ Config->ImageBase = Config->Pic ? 0 : Target->DefaultImageBase;
}
for (std::unique_ptr<InputFile> &F : Files)
Symtab.addFile(std::move(F));
+ if (HasError)
+ return; // There were duplicate symbols or incompatible files
- for (StringRef S : Config->Undefined)
- Symtab.addUndefinedOpt(S);
+ Symtab.scanUndefinedFlags();
+ Symtab.scanShlibUndefined();
+ Symtab.scanDynamicList();
+ Symtab.scanVersionScript();
+ Symtab.scanSymbolVersions();
+
+ Symtab.addCombinedLtoObject();
+ if (HasError)
+ return;
for (auto *Arg : Args.filtered(OPT_wrap))
Symtab.wrap(Arg->getValue());
- if (Config->OutputFile.empty())
- Config->OutputFile = "a.out";
-
// Write the result to the file.
- Symtab.scanShlibUndefined();
if (Config->GcSections)
- markLive<ELFT>(&Symtab);
+ markLive<ELFT>();
+ if (Config->ICF)
+ doIcf<ELFT>();
+
+ // MergeInputSection::splitIntoPieces needs to be called before
+ // any call of MergeInputSection::getOffset. Do that.
+ for (const std::unique_ptr<elf::ObjectFile<ELFT>> &F :
+ Symtab.getObjectFiles())
+ for (InputSectionBase<ELFT> *S : F->getSections()) {
+ if (!S || S == &InputSection<ELFT>::Discarded || !S->Live)
+ continue;
+ if (S->Compressed)
+ S->uncompress();
+ if (auto *MS = dyn_cast<MergeInputSection<ELFT>>(S))
+ MS->splitIntoPieces();
+ }
+
writeResult<ELFT>(&Symtab);
}
generated by cgit v1.2.3 (git 2.25.1) at 2025-10-04 18:04:00 +0000