diff --git a/lld/ELF/InputFiles.cpp b/lld/ELF/InputFiles.cpp
--- a/lld/ELF/InputFiles.cpp
+++ b/lld/ELF/InputFiles.cpp
@@ -632,6 +632,8 @@
       break;
     case SHT_SYMTAB:
     case SHT_STRTAB:
+    case SHT_REL:
+    case SHT_RELA:
     case SHT_NULL:
       break;
     default:
@@ -639,11 +641,21 @@
     }
   }
 
-  // This block handles SHF_LINK_ORDER.
+  // We have a second loop. It is used to:
+  // 1) handle SHF_LINK_ORDER sections.
+  // 2) create SHT_REL[A] sections. In some cases the section header index of a
+  //    relocation section may be smaller than that of the relocated section. In
+  //    such cases, the relocation section would attempt to reference a target
+  //    section that has not yet been created. For simplicity, delay creation of
+  //    relocation sections until now.
   for (size_t i = 0, e = objSections.size(); i < e; ++i) {
     if (this->sections[i] == &InputSection::discarded)
       continue;
     const Elf_Shdr &sec = objSections[i];
+
+    if (sec.sh_type == SHT_REL || sec.sh_type == SHT_RELA)
+      this->sections[i] = createInputSection(sec);
+
     if (!(sec.sh_flags & SHF_LINK_ORDER))
       continue;
 
diff --git a/lld/test/ELF/invalid/reloc-section-reordered.test b/lld/test/ELF/invalid/reloc-section-reordered.test
deleted file mode 100644
--- a/lld/test/ELF/invalid/reloc-section-reordered.test
+++ /dev/null
@@ -1,33 +0,0 @@
-# REQUIRES: x86
-
-# RUN: yaml2obj %s -o %t.o
-# RUN: not ld.lld %t.o -o /dev/null 2>&1 | FileCheck %s
-# CHECK: unsupported relocation reference
-
-## YAML below lists .rela.text before .text, we do not support it.
-
-!ELF
-FileHeader:
-  Class:           ELFCLASS64
-  Data:            ELFDATA2LSB
-  OSABI:           ELFOSABI_FREEBSD
-  Type:            ET_REL
-  Machine:         EM_X86_64
-Sections:
-  - Type:            SHT_REL
-    Name:            .rela.text
-    Link:            .symtab
-    Info:            .text
-    AddressAlign:    0x04
-    Relocations:
-      - Symbol:          .text
-        Type:            R_X86_64_NONE
-  - Type:            SHT_PROGBITS
-    Name:            .text
-    Flags:           [ SHF_ALLOC, SHF_EXECINSTR ]
-    AddressAlign:    0x04
-    Content:         "FFFFFFFFFFFFFFFF"
-Symbols:
-  - Name:    .text
-    Type:    STT_SECTION
-    Section: .text
diff --git a/lld/test/ELF/reloc-sec-before-relocated.test b/lld/test/ELF/reloc-sec-before-relocated.test
new file mode 100644
--- /dev/null
+++ b/lld/test/ELF/reloc-sec-before-relocated.test
@@ -0,0 +1,38 @@
+## If the section header index of a SHT_REL[A] section is smaller than the
+## section header index of the relocated section, we should handle it properly.
+## Normally it is not what compilers would emit, but some custom tools might
+## want to use this feature, which is not restricted by ELF gABI.
+## GNU ld supports this as well.
+
+# RUN: yaml2obj %s -DTYPE=SHT_RELA -o %t1.o
+# RUN: ld.lld -shared %t1.o -o %t1
+# RUN: llvm-readelf --relocs %t1 | FileCheck %s
+
+# RUN: yaml2obj %s -DTYPE=SHT_REL -o %t2.o
+# RUN: ld.lld -shared %t2.o -o %t2
+# RUN: llvm-readelf --relocs %t2 | FileCheck %s
+
+## Check we handle the relocation properly.
+# CHECK:      Relocation section '.rela.dyn' at offset 0x238 contains 1 entries:
+# CHECK-NEXT:     Offset             Info             Type    Symbol's Value  Symbol's Name + Addend
+# CHECK-NEXT: 00000000000022f0  0000000100000001 R_X86_64_64 0000000000000000 foo + 0
+
+--- !ELF
+FileHeader:
+  Class:   ELFCLASS64
+  Data:    ELFDATA2LSB
+  Type:    ET_REL
+  Machine: EM_X86_64
+Sections:
+  - Name:  .relx.data
+    Type:  [[TYPE]]
+    Info:  .data
+    Relocations:
+      - Symbol: foo
+        Type:   R_X86_64_64
+  - Name:  .data
+    Type:  SHT_PROGBITS
+    Flags: [ SHF_ALLOC, SHF_WRITE ]
+Symbols:
+  - Name:    foo
+    Binding: STB_GLOBAL