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-rw-r--r--lld/ELF/Config.h9
-rw-r--r--lld/ELF/SymbolListFile.cpp26
-rw-r--r--lld/ELF/SymbolTable.cpp72
-rw-r--r--lld/ELF/SymbolTable.h2
4 files changed, 81 insertions, 28 deletions
diff --git a/lld/ELF/Config.h b/lld/ELF/Config.h
index 8a8cc04b760..7412163624f 100644
--- a/lld/ELF/Config.h
+++ b/lld/ELF/Config.h
@@ -35,13 +35,18 @@ enum class BuildIdKind { None, Fnv1, Md5, Sha1, Hexstring };
enum class UnresolvedPolicy { NoUndef, Error, Warn, Ignore };
+struct SymbolVersion {
+ llvm::StringRef Name;
+ bool IsExternCpp;
+};
+
// This struct contains symbols version definition that
// can be found in version script if it is used for link.
struct Version {
Version(llvm::StringRef Name, size_t Id) : Name(Name), Id(Id) {}
llvm::StringRef Name;
size_t Id;
- std::vector<llvm::StringRef> Globals;
+ std::vector<SymbolVersion> Globals;
size_t NameOff; // Offset in string table.
};
@@ -68,7 +73,7 @@ struct Configuration {
std::vector<llvm::StringRef> DynamicList;
std::vector<llvm::StringRef> SearchPaths;
std::vector<llvm::StringRef> Undefined;
- std::vector<llvm::StringRef> VersionScriptGlobals;
+ std::vector<SymbolVersion> VersionScriptGlobals;
std::vector<uint8_t> BuildIdVector;
bool AllowMultipleDefinition;
bool AsNeeded = false;
diff --git a/lld/ELF/SymbolListFile.cpp b/lld/ELF/SymbolListFile.cpp
index 68867cf8ae6..1525540e259 100644
--- a/lld/ELF/SymbolListFile.cpp
+++ b/lld/ELF/SymbolListFile.cpp
@@ -77,6 +77,7 @@ public:
void run();
private:
+ void parseExtern(std::vector<SymbolVersion> *Globals);
void parseVersion(StringRef Version);
void parseLocal();
void parseVersionSymbols(StringRef Version);
@@ -120,21 +121,38 @@ void VersionScriptParser::parseLocal() {
Config->VersionScriptGlobalByDefault = false;
}
+void VersionScriptParser::parseExtern(std::vector<SymbolVersion> *Globals) {
+ expect("extern");
+ expect("C++");
+ expect("{");
+
+ for (;;) {
+ if (peek() == "}" || Error)
+ break;
+ Globals->push_back({next(), true});
+ expect(";");
+ }
+
+ expect("}");
+ expect(";");
+}
+
void VersionScriptParser::parseVersionSymbols(StringRef Version) {
- std::vector<StringRef> *Globals;
+ std::vector<SymbolVersion> *Globals;
if (Version.empty())
Globals = &Config->VersionScriptGlobals;
else
Globals = &Config->SymbolVersions.back().Globals;
for (;;) {
+ if (peek() == "extern")
+ parseExtern(Globals);
+
StringRef Cur = peek();
- if (Cur == "extern")
- setError("extern keyword is not supported");
if (Cur == "}" || Cur == "local:" || Error)
return;
next();
- Globals->push_back(Cur);
+ Globals->push_back({Cur, false});
expect(";");
}
}
diff --git a/lld/ELF/SymbolTable.cpp b/lld/ELF/SymbolTable.cpp
index 2474bb35a54..b3887249be0 100644
--- a/lld/ELF/SymbolTable.cpp
+++ b/lld/ELF/SymbolTable.cpp
@@ -567,6 +567,37 @@ static bool hasWildcard(StringRef S) {
return S.find_first_of("?*") != StringRef::npos;
}
+static void setVersionId(SymbolBody *Body, StringRef VersionName,
+ StringRef Name, uint16_t Version) {
+ if (!Body || Body->isUndefined()) {
+ if (Config->NoUndefinedVersion)
+ error("version script assignment of " + VersionName + " to symbol " +
+ Name + " failed: symbol not defined");
+ return;
+ }
+
+ Symbol *Sym = Body->symbol();
+ if (Sym->VersionId != VER_NDX_GLOBAL && Sym->VersionId != VER_NDX_LOCAL)
+ warning("duplicate symbol " + Name + " in version script");
+ Sym->VersionId = Version;
+}
+
+template <class ELFT>
+std::map<std::string, SymbolBody *> SymbolTable<ELFT>::getDemangledSyms() {
+ std::map<std::string, SymbolBody *> Result;
+ for (std::pair<SymName, unsigned> Sym : Symtab)
+ Result[demangle(Sym.first.Val)] = SymVector[Sym.second]->body();
+ return Result;
+}
+
+static bool hasExternCpp() {
+ for (Version& V : Config->SymbolVersions)
+ for (SymbolVersion Sym : V.Globals)
+ if (Sym.IsExternCpp)
+ return true;
+ return false;
+}
+
// This function processes the --version-script option by marking all global
// symbols with the VersionScriptGlobal flag, which acts as a filter on the
// dynamic symbol table.
@@ -574,8 +605,8 @@ template <class ELFT> void SymbolTable<ELFT>::scanVersionScript() {
// If version script does not contain versions declarations,
// we just should mark global symbols.
if (!Config->VersionScriptGlobals.empty()) {
- for (StringRef S : Config->VersionScriptGlobals)
- if (SymbolBody *B = find(S))
+ for (SymbolVersion &Sym : Config->VersionScriptGlobals)
+ if (SymbolBody *B = find(Sym.Name))
B->symbol()->VersionId = VER_NDX_GLOBAL;
return;
}
@@ -586,38 +617,35 @@ template <class ELFT> void SymbolTable<ELFT>::scanVersionScript() {
// If we have symbols version declarations, we should
// assign version references for each symbol.
// Current rules are:
- // * If there is an exact match for the mangled name, we use it.
+ // * If there is an exact match for the mangled name or we have extern C++
+ // exact match, then we use it.
// * Otherwise, we look through the wildcard patterns. We look through the
// version tags in reverse order. We use the first match we find (the last
// matching version tag in the file).
- for (size_t I = 0, E = Config->SymbolVersions.size(); I < E; ++I) {
- Version &V = Config->SymbolVersions[I];
- for (StringRef Name : V.Globals) {
- if (hasWildcard(Name))
- continue;
- SymbolBody *B = find(Name);
- if (!B || B->isUndefined()) {
- if (Config->NoUndefinedVersion)
- error("version script assignment of " + V.Name + " to symbol " +
- Name + " failed: symbol not defined");
- continue;
- }
+ // Handle exact matches and build a map of demangled externs for
+ // quick search during next step.
+ std::map<std::string, SymbolBody *> Demangled;
+ if (hasExternCpp())
+ Demangled = getDemangledSyms();
- if (B->symbol()->VersionId != VER_NDX_GLOBAL &&
- B->symbol()->VersionId != VER_NDX_LOCAL)
- warning("duplicate symbol " + Name + " in version script");
- B->symbol()->VersionId = V.Id;
+ for (Version &V : Config->SymbolVersions) {
+ for (SymbolVersion Sym : V.Globals) {
+ if (hasWildcard(Sym.Name))
+ continue;
+ SymbolBody *B = Sym.IsExternCpp ? Demangled[Sym.Name] : find(Sym.Name);
+ setVersionId(B, V.Name, Sym.Name, V.Id);
}
}
+ // Handle wildcards.
for (size_t I = Config->SymbolVersions.size() - 1; I != (size_t)-1; --I) {
Version &V = Config->SymbolVersions[I];
- for (StringRef Name : V.Globals) {
- if (!hasWildcard(Name))
+ for (SymbolVersion Sym : V.Globals) {
+ if (!hasWildcard(Sym.Name))
continue;
- for (SymbolBody *B : findAll(Name))
+ for (SymbolBody *B : findAll(Sym.Name))
if (B->symbol()->VersionId == VER_NDX_GLOBAL ||
B->symbol()->VersionId == VER_NDX_LOCAL)
B->symbol()->VersionId = V.Id;
diff --git a/lld/ELF/SymbolTable.h b/lld/ELF/SymbolTable.h
index 39a6ec96c09..9e26ffe86ea 100644
--- a/lld/ELF/SymbolTable.h
+++ b/lld/ELF/SymbolTable.h
@@ -97,6 +97,8 @@ private:
std::string conflictMsg(SymbolBody *Existing, InputFile *NewFile);
void reportDuplicate(SymbolBody *Existing, InputFile *NewFile);
+ std::map<std::string, SymbolBody *> getDemangledSyms();
+
// The order the global symbols are in is not defined. We can use an arbitrary
// order, but it has to be reproducible. That is true even when cross linking.
// The default hashing of StringRef produces different results on 32 and 64
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