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, 2 insertions, 2 deletions

diff --git a/lld/ELF/LinkerScript.cpp b/lld/ELF/LinkerScript.cpp
index 798f1947ba4..a5ca4a2e6e8 100644
--- a/lld/ELF/LinkerScript.cpp
+++ b/lld/ELF/LinkerScript.cpp
@@ -488,7 +488,7 @@ void LinkerScript::fabricateDefaultCommands() {
 // Add sections that didn't match any sections command.
 void LinkerScript::addOrphanSections(OutputSectionFactory &Factory) {
   for (InputSectionBase *S : InputSections) {
-    if (!S->Live || S->OutSec)
+    if (!S->Live || S->Parent)
       continue;
     StringRef Name = getOutputSectionName(S->Name);
     auto I = std::find_if(
@@ -602,7 +602,7 @@ void LinkerScript::process(BaseCommand &Base) {
 
     if (!Sec->Live)
       continue;
-    assert(CurOutSec == Sec->OutSec);
+    assert(CurOutSec == Sec->getParent());
     output(Sec);
   }
 }