Revert "Revert "[ELF] Suppress "STT_SECTION symbol should be defined" on .eh_frame, .debug*, .zdebug* and .gcc_except_table""

This reverts commit f49f58527a6d8147524d8d6f2eb1feb70f856292.

llvm-svn: 362744

1 files changed, 14 insertions, 3 deletions

diff --git a/lld/ELF/InputSection.cpp b/lld/ELF/InputSection.cpp
index 832e02cb2a8..d09eae1a2f4 100644
--- a/lld/ELF/InputSection.cpp
+++ b/lld/ELF/InputSection.cpp
@@ -412,7 +412,8 @@ void InputSection::copyRelocations(uint8_t *Buf, ArrayRef<RelTy> Rels) {
 
   for (const RelTy &Rel : Rels) {
     RelType Type = Rel.getType(Config->IsMips64EL);
-    Symbol &Sym = getFile<ELFT>()->getRelocTargetSym(Rel);
+    const ObjFile<ELFT> *File = getFile<ELFT>();
+    Symbol &Sym = File->getRelocTargetSym(Rel);
 
     auto *P = reinterpret_cast<typename ELFT::Rela *>(Buf);
     Buf += sizeof(RelTy);
@@ -435,10 +436,20 @@ void InputSection::copyRelocations(uint8_t *Buf, ArrayRef<RelTy> Rels) {
       // .eh_frame is horribly special and can reference discarded sections. To
       // avoid having to parse and recreate .eh_frame, we just replace any
       // relocation in it pointing to discarded sections with R_*_NONE, which
-      // hopefully creates a frame that is ignored at runtime.
+      // hopefully creates a frame that is ignored at runtime. Also, don't warn
+      // on .gcc_except_table and debug sections.
       auto *D = dyn_cast<Defined>(&Sym);
       if (!D) {
-        warn("STT_SECTION symbol should be defined");
+        if (!Sec->Name.startswith(".debug") &&
+            !Sec->Name.startswith(".zdebug") && Sec->Name != ".eh_frame" &&
+            Sec->Name != ".gcc_except_table") {
+          uint32_t SecIdx = cast<Undefined>(Sym).DiscardedSecIdx;
+          Elf_Shdr_Impl<ELFT> Sec =
+              CHECK(File->getObj().sections(), File)[SecIdx];
+          warn("relocation refers to a discarded section: " +
+               CHECK(File->getObj().getSectionName(&Sec), File) +
+               "\n>>> referenced by " + getObjMsg(P->r_offset));
+        }
         P->setSymbolAndType(0, 0, false);
         continue;
       }