From 49419bb30322ff00e143cbaad7af98221dd0c008 Mon Sep 17 00:00:00 2001
From: Rafael Espindola <rafael.espindola@gmail.com>
Date: Thu, 12 Oct 2017 15:05:04 +0000
Subject: [PATCH] Use 0 as sh_link when we don't have a dynamic symbol table.

It doesn't make sense to link from an alloc section to a non alloc
one as we were doing.

This matches the behavior of both gold and bfd.

llvm-svn: 315584
---
 lld/ELF/SyntheticSections.cpp    | 6 ++++--
 lld/test/ELF/aarch64-gnu-ifunc.s | 2 +-
 lld/test/ELF/gnu-ifunc-i386.s    | 2 +-
 lld/test/ELF/gnu-ifunc.s         | 2 +-
 4 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/lld/ELF/SyntheticSections.cpp b/lld/ELF/SyntheticSections.cpp
index 20d815ac216b..fc7971e32002 100644
--- a/lld/ELF/SyntheticSections.cpp
+++ b/lld/ELF/SyntheticSections.cpp
@@ -1284,8 +1284,10 @@ template <class ELFT> unsigned RelocationSection<ELFT>::getRelocOffset() {
 }
 
 template <class ELFT> void RelocationSection<ELFT>::finalizeContents() {
-  this->Link = InX::DynSymTab ? InX::DynSymTab->getParent()->SectionIndex
-                              : InX::SymTab->getParent()->SectionIndex;
+  // If all relocations are *RELATIVE they don't refer to any
+  // dynamic symbol and we don't need a dynamic symbol table. If that
+  // is the case, just use 0 as the link.
+  this->Link = InX::DynSymTab ? InX::DynSymTab->getParent()->SectionIndex : 0;
 
   // Set required output section properties.
   getParent()->Link = this->Link;
diff --git a/lld/test/ELF/aarch64-gnu-ifunc.s b/lld/test/ELF/aarch64-gnu-ifunc.s
index 46f4a292d2ea..4e0dc328025d 100644
--- a/lld/test/ELF/aarch64-gnu-ifunc.s
+++ b/lld/test/ELF/aarch64-gnu-ifunc.s
@@ -15,7 +15,7 @@
 // CHECK-NEXT:  Address: [[RELA:.*]]
 // CHECK-NEXT:  Offset: 0x158
 // CHECK-NEXT:  Size: 48
-// CHECK-NEXT:  Link: 6
+// CHECK-NEXT:  Link: 0
 // CHECK-NEXT:  Info: 0
 // CHECK-NEXT:  AddressAlignment: 8
 // CHECK-NEXT:  EntrySize: 24
diff --git a/lld/test/ELF/gnu-ifunc-i386.s b/lld/test/ELF/gnu-ifunc-i386.s
index 21f1313a9b05..559e98a3e625 100644
--- a/lld/test/ELF/gnu-ifunc-i386.s
+++ b/lld/test/ELF/gnu-ifunc-i386.s
@@ -15,7 +15,7 @@
 // CHECK-NEXT:  Address: [[RELA:.*]]
 // CHECK-NEXT:  Offset: 0xD4
 // CHECK-NEXT:  Size: 16
-// CHECK-NEXT:  Link: 6
+// CHECK-NEXT:  Link: 0
 // CHECK-NEXT:  Info: 0
 // CHECK-NEXT:  AddressAlignment: 4
 // CHECK-NEXT:  EntrySize: 8
diff --git a/lld/test/ELF/gnu-ifunc.s b/lld/test/ELF/gnu-ifunc.s
index f86f0300baaf..17883a3209f5 100644
--- a/lld/test/ELF/gnu-ifunc.s
+++ b/lld/test/ELF/gnu-ifunc.s
@@ -15,7 +15,7 @@
 // CHECK-NEXT:  Address: [[RELA:.*]]
 // CHECK-NEXT:  Offset: 0x158
 // CHECK-NEXT:  Size: 48
-// CHECK-NEXT:  Link: 6
+// CHECK-NEXT:  Link: 0
 // CHECK-NEXT:  Info: 0
 // CHECK-NEXT:  AddressAlignment: 8
 // CHECK-NEXT:  EntrySize: 24