diff --git a/lld/ELF/InputSection.cpp b/lld/ELF/InputSection.cpp
index ce20b5f0164b..d817fe12174f 100644
--- a/lld/ELF/InputSection.cpp
+++ b/lld/ELF/InputSection.cpp
@@ -482,9 +482,6 @@ template <class ELFT> void InputSection<ELFT>::writeTo(uint8_t *Buf) {
   if (this->Type == SHT_NOBITS)
     return;
 
-  // Set output location.
-  this->OutputLoc = Buf + OutSecOff;
-
   // If -r is given, then an InputSection may be a relocation section.
   if (this->Type == SHT_RELA) {
     copyRelocations(Buf + OutSecOff, this->template getDataAs<Elf_Rela>());
@@ -867,33 +864,38 @@ BuildIdSection<ELFT>::BuildIdSection(size_t HashSize)
 }
 
 template <class ELFT>
-void BuildIdFastHash<ELFT>::writeBuildId(ArrayRef<uint8_t> Buf) {
+uint8_t *BuildIdSection<ELFT>::getOutputLoc(uint8_t *Start) const {
+  return Start + this->OutSec->getFileOffset() + this->OutSecOff;
+}
+
+template <class ELFT>
+void BuildIdFastHash<ELFT>::writeBuildId(MutableArrayRef<uint8_t> Buf) {
   const endianness E = ELFT::TargetEndianness;
 
   // 64-bit xxhash
   uint64_t Hash = xxHash64(toStringRef(Buf));
-  write64<E>(this->OutputLoc + 16, Hash);
+  write64<E>(this->getOutputLoc(Buf.begin()) + 16, Hash);
 }
 
 template <class ELFT>
-void BuildIdMd5<ELFT>::writeBuildId(ArrayRef<uint8_t> Buf) {
+void BuildIdMd5<ELFT>::writeBuildId(MutableArrayRef<uint8_t> Buf) {
   MD5 Hash;
   Hash.update(Buf);
   MD5::MD5Result Res;
   Hash.final(Res);
-  memcpy(this->OutputLoc + 16, Res, 16);
+  memcpy(this->getOutputLoc(Buf.begin()) + 16, Res, 16);
 }
 
 template <class ELFT>
-void BuildIdSha1<ELFT>::writeBuildId(ArrayRef<uint8_t> Buf) {
+void BuildIdSha1<ELFT>::writeBuildId(MutableArrayRef<uint8_t> Buf) {
   SHA1 Hash;
   Hash.update(Buf);
-  memcpy(this->OutputLoc + 16, Hash.final().data(), 20);
+  memcpy(this->getOutputLoc(Buf.begin()) + 16, Hash.final().data(), 20);
 }
 
 template <class ELFT>
-void BuildIdUuid<ELFT>::writeBuildId(ArrayRef<uint8_t> Buf) {
-  if (getRandomBytes(this->OutputLoc + 16, 16))
+void BuildIdUuid<ELFT>::writeBuildId(MutableArrayRef<uint8_t> Buf) {
+  if (getRandomBytes(this->getOutputLoc(Buf.begin()) + 16, 16))
     error("entropy source failure");
 }
 
@@ -902,8 +904,8 @@ BuildIdHexstring<ELFT>::BuildIdHexstring()
     : BuildIdSection<ELFT>(Config->BuildIdVector.size()) {}
 
 template <class ELFT>
-void BuildIdHexstring<ELFT>::writeBuildId(ArrayRef<uint8_t> Buf) {
-  memcpy(this->OutputLoc + 16, Config->BuildIdVector.data(),
+void BuildIdHexstring<ELFT>::writeBuildId(MutableArrayRef<uint8_t> Buf) {
+  memcpy(this->getOutputLoc(Buf.begin()) + 16, Config->BuildIdVector.data(),
          Config->BuildIdVector.size());
 }
 
diff --git a/lld/ELF/InputSection.h b/lld/ELF/InputSection.h
index e4b23dfad120..338368a9dab0 100644
--- a/lld/ELF/InputSection.h
+++ b/lld/ELF/InputSection.h
@@ -252,9 +252,6 @@ public:
   // to. The writer sets a value.
   uint64_t OutSecOff = 0;
 
-  // Location of this section in the output buffer
-  uint8_t *OutputLoc = nullptr;
-
   // InputSection that is dependent on us (reverse dependency for GC)
   InputSectionBase<ELFT> *DependentSection = nullptr;
 
@@ -344,9 +341,11 @@ public:
 
 template <class ELFT> class BuildIdSection : public InputSection<ELFT> {
 public:
-  virtual void writeBuildId(ArrayRef<uint8_t> Buf) = 0;
+  virtual void writeBuildId(llvm::MutableArrayRef<uint8_t> Buf) = 0;
   virtual ~BuildIdSection() = default;
 
+  uint8_t *getOutputLoc(uint8_t *Start) const;
+
 protected:
   BuildIdSection(size_t HashSize);
   std::vector<uint8_t> Buf;
@@ -356,32 +355,32 @@ template <class ELFT>
 class BuildIdFastHash final : public BuildIdSection<ELFT> {
 public:
   BuildIdFastHash() : BuildIdSection<ELFT>(8) {}
-  void writeBuildId(ArrayRef<uint8_t> Buf) override;
+  void writeBuildId(llvm::MutableArrayRef<uint8_t> Buf) override;
 };
 
 template <class ELFT> class BuildIdMd5 final : public BuildIdSection<ELFT> {
 public:
   BuildIdMd5() : BuildIdSection<ELFT>(16) {}
-  void writeBuildId(ArrayRef<uint8_t> Buf) override;
+  void writeBuildId(llvm::MutableArrayRef<uint8_t> Buf) override;
 };
 
 template <class ELFT> class BuildIdSha1 final : public BuildIdSection<ELFT> {
 public:
   BuildIdSha1() : BuildIdSection<ELFT>(20) {}
-  void writeBuildId(ArrayRef<uint8_t> Buf) override;
+  void writeBuildId(llvm::MutableArrayRef<uint8_t> Buf) override;
 };
 
 template <class ELFT> class BuildIdUuid final : public BuildIdSection<ELFT> {
 public:
   BuildIdUuid() : BuildIdSection<ELFT>(16) {}
-  void writeBuildId(ArrayRef<uint8_t> Buf) override;
+  void writeBuildId(llvm::MutableArrayRef<uint8_t> Buf) override;
 };
 
 template <class ELFT>
 class BuildIdHexstring final : public BuildIdSection<ELFT> {
 public:
   BuildIdHexstring();
-  void writeBuildId(ArrayRef<uint8_t>) override;
+  void writeBuildId(llvm::MutableArrayRef<uint8_t>) override;
 };
 
 // Linker generated sections which can be used as inputs.