Reland r319090, "COFF: Do not create SectionChunks for discarded comdat sections." with a fix for debug sections.

If /debug was not specified, readSection will return a null
pointer for debug sections. If the debug section is associative with
another section, we need to make sure that the section returned from
readSection is not a null pointer before adding it as an associative
section.

Differential Revision: https://reviews.llvm.org/D40533

llvm-svn: 319133

1 files changed, 2 insertions, 9 deletions

diff --git a/lld/COFF/Chunks.cpp b/lld/COFF/Chunks.cpp
index e83a8c6e458..df98a041cd5 100644
--- a/lld/COFF/Chunks.cpp
+++ b/lld/COFF/Chunks.cpp
@@ -38,9 +38,6 @@ SectionChunk::SectionChunk(ObjFile *F, const coff_section *H)
 
   Alignment = Header->getAlignment();
 
-  // Chunks may be discarded during comdat merging.
-  Discarded = false;
-
   // If linker GC is disabled, every chunk starts out alive.  If linker GC is
   // enabled, treat non-comdat sections as roots. Generally optimized object
   // files will be built with -ffunction-sections or /Gy, so most things worth
@@ -362,12 +359,8 @@ bool SectionChunk::isCOMDAT() const {
 void SectionChunk::printDiscardedMessage() const {
   // Removed by dead-stripping. If it's removed by ICF, ICF already
   // printed out the name, so don't repeat that here.
-  if (Sym && this == Repl) {
-    if (Discarded)
-      message("Discarded comdat symbol " + Sym->getName());
-    else if (!Live)
-      message("Discarded " + Sym->getName());
-  }
+  if (Sym && this == Repl)
+    message("Discarded " + Sym->getName());
 }
 
 StringRef SectionChunk::getDebugName() {