void PECOFFLinkingContext::addDllExport(ExportDesc &desc) {
addInitialUndefinedSymbol(allocate(desc.name));
// MSVC link.exe silently drops characters after the first atsign.
// For example, /export:foo@4=bar is equivalent to /export:foo=bar.
// We do the same thing for compatibility.
if (!desc.externalName.empty()) {
StringRef s(desc.externalName);
size_t pos = s.find('@');
if (pos != s.npos)
desc.externalName = s.substr(0, pos);
}
// Scan the vector to look for existing entry. It's not very fast,
// but because the number of exported symbol is usually not that
// much, it should be okay.
for (ExportDesc &e : _dllExports) {
if (e.name != desc.name)
continue;
if (!sameExportDesc(e, desc))
llvm::errs() << "Export symbol '" << desc.name
<< "' specified more than once.\n";
return;
}
_dllExports.push_back(desc);
}
bool MachOLinkingContext::validateImpl(raw_ostream &diagnostics) {
// TODO: if -arch not specified, look at arch of first .o file.
if (_currentVersion && _outputMachOType != MH_DYLIB) {
diagnostics << "error: -current_version can only be used with dylibs\n";
return false;
}
if (_compatibilityVersion && _outputMachOType != MH_DYLIB) {
diagnostics
<< "error: -compatibility_version can only be used with dylibs\n";
return false;
}
if (_deadStrippableDylib && _outputMachOType != MH_DYLIB) {
diagnostics
<< "error: -mark_dead_strippable_dylib can only be used with dylibs.\n";
return false;
}
if (!_bundleLoader.empty() && outputMachOType() != MH_BUNDLE) {
diagnostics
<< "error: -bundle_loader can only be used with Mach-O bundles\n";
return false;
}
// If -exported_symbols_list used, all exported symbols must be defined.
if (_exportMode == ExportMode::whiteList) {
for (const auto &symbol : _exportedSymbols)
addInitialUndefinedSymbol(symbol.getKey());
}
// If -dead_strip, set up initial live symbols.
if (deadStrip()) {
// Entry point is live.
if (outputTypeHasEntry())
addDeadStripRoot(entrySymbolName());
// Lazy binding helper is live.
if (needsStubsPass())
addDeadStripRoot(binderSymbolName());
// If using -exported_symbols_list, make all exported symbols live.
if (_exportMode == ExportMode::whiteList) {
setGlobalsAreDeadStripRoots(false);
for (const auto &symbol : _exportedSymbols)
addDeadStripRoot(symbol.getKey());
}
}
addOutputFileDependency(outputPath());
return true;
}
