From 61d052d7251b4b3e78d2524f7c7f6fc949ec87e2 Mon Sep 17 00:00:00 2001
From: Rafael Espindola <rafael.espindola@gmail.com>
Date: Sun, 4 Dec 2016 08:34:17 +0000
Subject: [PATCH] Don't discard .L symbol with -r.

They might be used by relocations.

Fixes pr31252.

llvm-svn: 288617
---
 lld/ELF/Driver.cpp                   |  4 +++-
 lld/test/ELF/relocatable-local-sym.s | 16 ++++++++++++++++
 2 files changed, 19 insertions(+), 1 deletion(-)
 create mode 100644 lld/test/ELF/relocatable-local-sym.s

diff --git a/lld/ELF/Driver.cpp b/lld/ELF/Driver.cpp
index d8c486672f20..cb27adc2d227 100644
--- a/lld/ELF/Driver.cpp
+++ b/lld/ELF/Driver.cpp
@@ -420,6 +420,8 @@ static bool getArg(opt::InputArgList &Args, unsigned K1, unsigned K2,
 }
 
 static DiscardPolicy getDiscardOption(opt::InputArgList &Args) {
+  if (Config->Relocatable)
+    return DiscardPolicy::None;
   auto *Arg =
       Args.getLastArg(OPT_discard_all, OPT_discard_locals, OPT_discard_none);
   if (!Arg)
@@ -515,7 +517,6 @@ void LinkerDriver::readConfigs(opt::InputArgList &Args) {
   Config->BsymbolicFunctions = Args.hasArg(OPT_Bsymbolic_functions);
   Config->Demangle = getArg(Args, OPT_demangle, OPT_no_demangle, true);
   Config->DisableVerify = Args.hasArg(OPT_disable_verify);
-  Config->Discard = getDiscardOption(Args);
   Config->EhFrameHdr = Args.hasArg(OPT_eh_frame_hdr);
   Config->EnableNewDtags = !Args.hasArg(OPT_disable_new_dtags);
   Config->ExportDynamic = Args.hasArg(OPT_export_dynamic);
@@ -530,6 +531,7 @@ void LinkerDriver::readConfigs(opt::InputArgList &Args) {
   Config->Pie = getArg(Args, OPT_pie, OPT_nopie, false);
   Config->PrintGcSections = Args.hasArg(OPT_print_gc_sections);
   Config->Relocatable = Args.hasArg(OPT_relocatable);
+  Config->Discard = getDiscardOption(Args);
   Config->SaveTemps = Args.hasArg(OPT_save_temps);
   Config->SingleRoRx = Args.hasArg(OPT_no_rosegment);
   Config->Shared = Args.hasArg(OPT_shared);
diff --git a/lld/test/ELF/relocatable-local-sym.s b/lld/test/ELF/relocatable-local-sym.s
new file mode 100644
index 000000000000..b894d6b9900c
--- /dev/null
+++ b/lld/test/ELF/relocatable-local-sym.s
@@ -0,0 +1,16 @@
+# REQUIRES: x86
+# RUN: llvm-mc -filetype=obj -triple=x86_64-pc-linux %s -o %t1.o
+# RUN: ld.lld -r %t1.o -o %t2.o
+# RUN: llvm-readobj -r %t2.o | FileCheck %s
+
+# CHECK:      Relocations [
+# CHECK-NEXT:   Section ({{.*}}) .rela.text {
+# CHECK-NEXT:     0x3 R_X86_64_PC32 .Lstr 0xFFFFFFFFFFFFFFFC
+# CHECK-NEXT:   }
+# CHECK-NEXT: ]
+
+        leaq    .Lstr(%rip), %rdi
+
+        .section        .rodata.str1.1,"aMS",@progbits,1
+        .Lstr:
+        .asciz "abc\n"