Store a single Parent pointer for InputSectionBase.

Before InputSectionBase had an OutputSection pointer, but that was not
always valid. For example, if it was a merge section one actually had
to look at MergeSec->OutSec.

This was brittle and caused bugs like the one fixed by r304260.

We now have a single Parent pointer that points to an OutputSection
for InputSection, but to a SyntheticSection for merge sections and
.eh_frame. This makes it impossible to accidentally access an invalid
OutSec.

llvm-svn: 304338

1 files changed, 4 insertions, 4 deletions

diff --git a/lld/ELF/Symbols.cpp b/lld/ELF/Symbols.cpp
index 7ce1f5354b1..67e57d9c8f0 100644
--- a/lld/ELF/Symbols.cpp
+++ b/lld/ELF/Symbols.cpp
@@ -101,12 +101,12 @@ static uint64_t getSymVA(const SymbolBody &Body, int64_t &Addend) {
   case SymbolBody::DefinedCommonKind:
     if (!Config->DefineCommon)
       return 0;
-    return InX::Common->OutSec->Addr + InX::Common->OutSecOff +
+    return InX::Common->getParent()->Addr + InX::Common->OutSecOff +
            cast<DefinedCommon>(Body).Offset;
   case SymbolBody::SharedKind: {
     auto &SS = cast<SharedSymbol>(Body);
     if (SS.NeedsCopy)
-      return SS.CopyRelSec->OutSec->Addr + SS.CopyRelSec->OutSecOff +
+      return SS.CopyRelSec->getParent()->Addr + SS.CopyRelSec->OutSecOff +
              SS.CopyRelSecOff;
     if (SS.NeedsPltAddr)
       return Body.getPltVA();
@@ -207,13 +207,13 @@ OutputSection *SymbolBody::getOutputSection() const {
 
   if (auto *S = dyn_cast<SharedSymbol>(this)) {
     if (S->NeedsCopy)
-      return S->CopyRelSec->OutSec;
+      return S->CopyRelSec->getParent();
     return nullptr;
   }
 
   if (isa<DefinedCommon>(this)) {
     if (Config->DefineCommon)
-      return InX::Common->OutSec;
+      return InX::Common->getParent();
     return nullptr;
   }