gistfile1.txt

diff --git a/ELF/OutputSections.cpp b/ELF/OutputSections.cpp
index b885601..1a6fbc1 100644
--- a/ELF/OutputSections.cpp
+++ b/ELF/OutputSections.cpp
@@ -1385,18 +1385,22 @@ StringTableSection<ELFT>::StringTableSection(StringRef Name, bool Dynamic)
 // we obtained in the former function can be written in the latter.
 // This design eliminated that need.
 template <class ELFT> void StringTableSection<ELFT>::reserve(StringRef S) {
-  Reserved += S.size() + 1; // +1 for NUL
+  if (Seen.insert(S).second)
+    Reserved += S.size() + 1; // +1 for NUL
 }

 // Adds a string to the string table. You must call reserve() with the
 // same string before calling addString().
 template <class ELFT> size_t StringTableSection<ELFT>::addString(StringRef S) {
-  size_t Pos = Used;
+  size_t &Off = Offsets[S];
+  if (Off)
+    return Off;
+  Off = Used;
   Strings.push_back(S);
   Used += S.size() + 1;
   Reserved -= S.size() + 1;
   assert((int64_t)Reserved >= 0);
-  return Pos;
+  return Off;
 }

 template <class ELFT> void StringTableSection<ELFT>::writeTo(uint8_t *Buf) {
diff --git a/ELF/OutputSections.h b/ELF/OutputSections.h
index 7132413..173b91b 100644
--- a/ELF/OutputSections.h
+++ b/ELF/OutputSections.h
@@ -19,6 +19,8 @@
 #include "Config.h"

 #include <type_traits>
+#include <set>
+#include <map>

 namespace lld {
 namespace elf2 {
@@ -339,6 +341,8 @@ public:
   bool isDynamic() const { return Dynamic; }

 private:
+  std::set<std::string> Seen;
+  std::map<std::string, size_t> Offsets;
   const bool Dynamic;
   std::vector<StringRef> Strings;
   size_t Used = 1; // ELF string tables start with a NUL byte, so 1.