[ELF] - Do not crash with --emit-relocs and --icf=all together.

Previously we would crash because did not mark .rel[a] sections
as dead and they tried to access parent which was not live
after ICF and therefore was null.

Differential revision: https://reviews.llvm.org/D43241

llvm-svn: 325877

diff --git a/lld/ELF/InputSection.cpp b/lld/ELF/InputSection.cpp
index f7a757e..f6676af 100644 (file)
--- a/lld/ELF/InputSection.cpp
+++ b/lld/ELF/InputSection.cpp
@@ -789,6 +789,8 @@ void InputSection::replace(InputSection *Other) {
   Alignment = std::max(Alignment, Other->Alignment);
   Other->Repl = Repl;
   Other->Live = false;
+  for (InputSection *IS : Other->DependentSections)
+    IS->Live = false;
 }
 
 template <class ELFT>

diff --git a/lld/test/ELF/emit-relocs-icf.s b/lld/test/ELF/emit-relocs-icf.s
new file mode 100644 (file)
index 0000000..59e003f
--- /dev/null
+++ b/lld/test/ELF/emit-relocs-icf.s
@@ -0,0 +1,33 @@
+# REQUIRES: x86
+# RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t1.o
+# RUN: ld.lld --emit-relocs --icf=all %t1.o -o %t
+# RUN: llvm-readobj -r %t | FileCheck %s
+
+# CHECK:      Relocations [
+# CHECK-NEXT:   Section {{.*}} .rela.text {
+# CHECK-NEXT:     R_X86_64_32 .text 0x1
+# CHECK-NEXT:     R_X86_64_PLT32 fn 0xFFFFFFFFFFFFFFFC
+# CHECK-NEXT:   }
+# CHECK-NEXT: ]
+
+.section .text.fn,"ax",@progbits,unique,0
+.globl fn
+.type fn,@function
+fn:
+ nop
+
+bar:
+  movl $bar, %edx
+  callq fn@PLT
+  nop
+
+.section .text.fn2,"ax",@progbits,unique,1
+.globl fn2
+.type fn2,@function
+fn2:
+ nop
+
+foo:
+  movl $foo, %edx
+  callq fn2@PLT
+  nop