[ELF] - Give automatically generated __start_* and __stop_* symbols default visibility.

This patch is opposite to D19024, which made this symbols to be hidden by default.

Unfortunately FreeBSD loader wants to see
start_set_modmetadata_set/stop_set_modmetadata_set in the dynamic symbol table. 
They were not placed there because had hidden visibility.

Patch makes them to have default visibility again.

Differential revision: https://reviews.llvm.org/D23552

llvm-svn: 279262

1 files changed, 9 insertions, 7 deletions

diff --git a/lld/ELF/Writer.cpp b/lld/ELF/Writer.cpp
index ecbbc0a3352..b39897f8200 100644
--- a/lld/ELF/Writer.cpp
+++ b/lld/ELF/Writer.cpp
@@ -519,7 +519,7 @@ static Symbol *addOptionalSynthetic(StringRef Name,
     return nullptr;
   if (!S->isUndefined() && !S->isShared())
     return S->symbol();
-  return Symtab<ELFT>::X->addSynthetic(Name, Sec, Val);
+  return Symtab<ELFT>::X->addSynthetic(Name, Sec, Val, STV_HIDDEN);
 }
 
 template <class ELFT>
@@ -527,7 +527,7 @@ static void addSynthetic(StringRef Name, OutputSectionBase<ELFT> *Sec,
                                  typename ELFT::uint Val) {
   SymbolBody *S = Symtab<ELFT>::X->find(Name);
   if (!S || S->isUndefined() || S->isShared())
-    Symtab<ELFT>::X->addSynthetic(Name, Sec, Val);
+    Symtab<ELFT>::X->addSynthetic(Name, Sec, Val, STV_HIDDEN);
 }
 // The beginning and the ending of .rel[a].plt section are marked
 // with __rel[a]_iplt_{start,end} symbols if it is a statically linked
@@ -554,7 +554,8 @@ template <class ELFT> void Writer<ELFT>::addReservedSymbols() {
     // 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<ELFT>::X->addSynthetic("_gp", Out<ELFT>::Got, MipsGPOffset);
+    Symtab<ELFT>::X->addSynthetic("_gp", Out<ELFT>::Got, MipsGPOffset,
+                                  STV_HIDDEN);
 
     // On MIPS O32 ABI, _gp_disp is a magic symbol designates offset between
     // start of function and 'gp' pointer into GOT.
@@ -701,7 +702,8 @@ template <class ELFT> void Writer<ELFT>::finalizeSections() {
   // Even the author of gold doesn't remember why gold behaves that way.
   // https://sourceware.org/ml/binutils/2002-03/msg00360.html
   if (Out<ELFT>::DynSymTab)
-    Symtab<ELFT>::X->addSynthetic("_DYNAMIC", Out<ELFT>::Dynamic, 0);
+    Symtab<ELFT>::X->addSynthetic("_DYNAMIC", Out<ELFT>::Dynamic, 0,
+                                  STV_HIDDEN);
 
   // Define __rel[a]_iplt_{start,end} symbols if needed.
   addRelIpltSymbols();
@@ -893,11 +895,11 @@ void Writer<ELFT>::addStartStopSymbols(OutputSectionBase<ELFT> *Sec) {
   StringRef Stop = Saver.save("__stop_" + S);
   if (SymbolBody *B = Symtab<ELFT>::X->find(Start))
     if (B->isUndefined())
-      Symtab<ELFT>::X->addSynthetic(Start, Sec, 0);
+      Symtab<ELFT>::X->addSynthetic(Start, Sec, 0, B->getVisibility());
   if (SymbolBody *B = Symtab<ELFT>::X->find(Stop))
     if (B->isUndefined())
-      Symtab<ELFT>::X->addSynthetic(Stop, Sec,
-                                    DefinedSynthetic<ELFT>::SectionEnd);
+      Symtab<ELFT>::X->addSynthetic(
+          Stop, Sec, DefinedSynthetic<ELFT>::SectionEnd, B->getVisibility());
 }
 
 template <class ELFT>