Internalize symbols in comdats.

We were dropping the CanOmitFromDynSym bit when creating undefined symbols because of comdat. llvm-svn: 272812
llvm · Jun 15, 2016 · cc70da3 · cc70da3
1 parent 6100adf
commit cc70da3
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Showing 4 changed files with 21 additions and 7 deletions.
diff --git a/lld/ELF/InputFiles.cpp b/lld/ELF/InputFiles.cpp
@@ -351,7 +351,8 @@ SymbolBody *elf::ObjectFile<ELFT>::createSymbolBody(const Elf_Sym *Sym) {
   switch (Sym->st_shndx) {
   case SHN_UNDEF:
     return elf::Symtab<ELFT>::X
-        ->addUndefined(Name, Binding, Sym->st_other, Sym->getType(), this)
+        ->addUndefined(Name, Binding, Sym->st_other, Sym->getType(),
+                       /*CanOmitFromDynSym*/ false, this)
         ->body();
   case SHN_COMMON:
     return elf::Symtab<ELFT>::X
@@ -368,7 +369,8 @@ SymbolBody *elf::ObjectFile<ELFT>::createSymbolBody(const Elf_Sym *Sym) {
   case STB_GNU_UNIQUE:
     if (Sec == &InputSection<ELFT>::Discarded)
       return elf::Symtab<ELFT>::X
-          ->addUndefined(Name, Binding, Sym->st_other, Sym->getType(), this)
+          ->addUndefined(Name, Binding, Sym->st_other, Sym->getType(),
+                         /*CanOmitFromDynSym*/ false, this)
           ->body();
     return elf::Symtab<ELFT>::X->addRegular(Name, *Sym, Sec)->body();
   }
@@ -589,12 +591,12 @@ Symbol *BitcodeFile::createSymbol(const DenseSet<const Comdat *> &KeptComdats,
     if (const Comdat *C = GV->getComdat())
       if (!KeptComdats.count(C))
         return Symtab<ELFT>::X->addUndefined(NameRef, Binding, Visibility, Type,
-                                             this);
+                                             CanOmitFromDynSym, this);
 
   const Module &M = Obj.getModule();
   if (Flags & BasicSymbolRef::SF_Undefined)
     return Symtab<ELFT>::X->addUndefined(NameRef, Binding, Visibility, Type,
-                                         this);
+                                         CanOmitFromDynSym, this);
   if (Flags & BasicSymbolRef::SF_Common) {
     // FIXME: Set SF_Common flag correctly for module asm symbols, and expose
     // size and alignment.

diff --git a/lld/ELF/SymbolTable.cpp b/lld/ELF/SymbolTable.cpp
@@ -220,17 +220,18 @@ std::string SymbolTable<ELFT>::conflictMsg(SymbolBody *Existing,
 
 template <class ELFT> Symbol *SymbolTable<ELFT>::addUndefined(StringRef Name) {
   return addUndefined(Name, STB_GLOBAL, STV_DEFAULT, /*Type*/ 0,
-                      /*File*/ nullptr);
+                      /*CanOmitFromDynSym*/ false, /*File*/ nullptr);
 }
 
 template <class ELFT>
 Symbol *SymbolTable<ELFT>::addUndefined(StringRef Name, uint8_t Binding,
                                         uint8_t StOther, uint8_t Type,
+                                        bool CanOmitFromDynSym,
                                         InputFile *File) {
   Symbol *S;
   bool WasInserted;
   std::tie(S, WasInserted) =
-      insert(Name, Type, StOther & 3, /*CanOmitFromDynSym*/ false,
+      insert(Name, Type, StOther & 3, CanOmitFromDynSym,
              /*IsUsedInRegularObj*/ !File || !isa<BitcodeFile>(File), File);
   if (WasInserted) {
     S->Binding = Binding;

diff --git a/lld/ELF/SymbolTable.h b/lld/ELF/SymbolTable.h
@@ -59,7 +59,7 @@ template <class ELFT> class SymbolTable {
 
   Symbol *addUndefined(StringRef Name);
   Symbol *addUndefined(StringRef Name, uint8_t Binding, uint8_t StOther,
-                       uint8_t Type, InputFile *File);
+                       uint8_t Type, bool CanOmitFromDynSym, InputFile *File);
 
   Symbol *addRegular(StringRef Name, const Elf_Sym &Sym,
                      InputSectionBase<ELFT> *Section);

diff --git a/lld/test/ELF/lto/unnamed-addr-comdat.ll b/lld/test/ELF/lto/unnamed-addr-comdat.ll
@@ -0,0 +1,11 @@
+; RUN: llvm-as %s -o %t.o
+; RUN: ld.lld -m elf_x86_64 %t.o %t.o -o %t.so -save-temps -shared
+; RUN: llvm-dis %t.so.lto.bc -o - | FileCheck %s
+
+target triple = "x86_64-unknown-linux-gnu"
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+
+$foo = comdat any
+@foo = linkonce_odr unnamed_addr constant i32 42, comdat
+
+; CHECK: @foo = internal unnamed_addr constant i32 42, comdat