Index: ELF/OutputSections.h
===================================================================
--- ELF/OutputSections.h
+++ ELF/OutputSections.h
@@ -115,6 +115,7 @@
   StringRef Name;
   uint64_t Flags;
   uint32_t Alignment;
+  uint32_t Info;
 };
 }
 }
Index: ELF/OutputSections.cpp
===================================================================
--- ELF/OutputSections.cpp
+++ ELF/OutputSections.cpp
@@ -322,13 +322,18 @@
   // incompatible types and flags.
 
   uint32_t Alignment = 0;
+  uint32_t Info = 0;
   uint64_t Flags = 0;
-  if (Config->Relocatable && (C->Flags & SHF_MERGE)) {
-    Alignment = std::max<uint64_t>(C->Alignment, C->Entsize);
-    Flags = C->Flags & (SHF_MERGE | SHF_STRINGS);
+  if (Config->Relocatable) {
+    if (C->Flags & SHF_MERGE) {
+      Alignment = std::max<uint64_t>(C->Alignment, C->Entsize);
+      Flags = C->Flags & (SHF_MERGE | SHF_STRINGS);
+    }
+    if (C->Type == SHT_GROUP)
+      Info = C->Info;
   }
 
-  return SectionKey{OutsecName, Flags, Alignment};
+  return SectionKey{OutsecName, Flags, Alignment, Info};
 }
 
 OutputSectionFactory::OutputSectionFactory(
@@ -413,13 +418,14 @@
 }
 
 unsigned DenseMapInfo<SectionKey>::getHashValue(const SectionKey &Val) {
-  return hash_combine(Val.Name, Val.Flags, Val.Alignment);
+  return hash_combine(Val.Name, Val.Flags, Val.Alignment, Val.Info);
 }
 
 bool DenseMapInfo<SectionKey>::isEqual(const SectionKey &LHS,
                                        const SectionKey &RHS) {
   return DenseMapInfo<StringRef>::isEqual(LHS.Name, RHS.Name) &&
-         LHS.Flags == RHS.Flags && LHS.Alignment == RHS.Alignment;
+         LHS.Flags == RHS.Flags && LHS.Alignment == RHS.Alignment &&
+         LHS.Info == RHS.Info;
 }
 
 uint64_t elf::getHeaderSize() {
Index: test/ELF/relocatable-comdat-multiple.s
===================================================================
--- test/ELF/relocatable-comdat-multiple.s
+++ test/ELF/relocatable-comdat-multiple.s
@@ -0,0 +1,33 @@
+# REQUIRES: x86
+# RUN: llvm-mc -filetype=obj -triple=x86_64-pc-linux %s -o %t.o
+# RUN: ld.lld -r %t.o %t.o -o %t
+# RUN: llvm-readobj -elf-section-groups %t | FileCheck %s
+
+# CHECK:      Groups {
+# CHECK-NEXT:   Group {
+# CHECK-NEXT:     Name: .group
+# CHECK-NEXT:     Index: 2
+# CHECK-NEXT:     Type: COMDAT
+# CHECK-NEXT:     Signature: aaa
+# CHECK-NEXT:     Section(s) in group [
+# CHECK-NEXT:       .text.a
+# CHECK-NEXT:       .text.b
+# CHECK-NEXT:     ]
+# CHECK-NEXT:   }
+# CHECK-NEXT:   Group {
+# CHECK-NEXT:     Name: .group
+# CHECK-NEXT:     Index: 5
+# CHECK-NEXT:     Type: COMDAT
+# CHECK-NEXT:     Signature: bbb
+# CHECK-NEXT:     Section(s) in group [
+# CHECK-NEXT:       .text.c
+# CHECK-NEXT:       .text.d
+# CHECK-NEXT:     ]
+# CHECK-NEXT:   }
+# CHECK-NEXT: }
+
+.section .text.a,"axG",@progbits,aaa,comdat
+.section .text.b,"axG",@progbits,aaa,comdat
+
+.section .text.c,"axG",@progbits,bbb,comdat
+.section .text.d,"axG",@progbits,bbb,comdat