[lld] r314095 - Do not sort CU vectors.

[Rui Ueyama via llvm-commits]

Author: ruiu
Date: Sun Sep 24 22:30:39 2017
New Revision: 314095

URL: http://llvm.org/viewvc/llvm-project?rev=314095&view=rev
Log:
Do not sort CU vectors.

We used to sort and uniquify CU vectors, but looks like CU vectors in
.gdb_index sections created by gold are not guaranteed to be sorted.

Modified:
    lld/trunk/ELF/SyntheticSections.cpp

Modified: lld/trunk/ELF/SyntheticSections.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/SyntheticSections.cpp?rev=314095&r1=314094&r2=314095&view=diff
==============================================================================
--- lld/trunk/ELF/SyntheticSections.cpp (original)
+++ lld/trunk/ELF/SyntheticSections.cpp Sun Sep 24 22:30:39 2017
@@ -1797,16 +1797,17 @@ std::vector<std::vector<uint32_t>> GdbIn
         Off += Ent.Name.size() + 1;
         Ret.push_back({});
       }
-      Ret[Sym->CuVectorIndex].push_back((Ent.Type << 24) | Idx);
+
+      // gcc 5.4.1 produces a buggy .debug_gnu_pubnames that contains
+      // duplicate entries, so we want to dedup them.
+      std::vector<uint32_t> &Vec = Ret[Sym->CuVectorIndex];
+      uint32_t Val = (Ent.Type << 24) | Idx;
+      if (Vec.empty() || Vec.back() != Val)
+        Vec.push_back(Val);
     }
     Idx += Chunk.CompilationUnits.size();
   }
 
-  for (std::vector<uint32_t> &V : Ret) {
-    std::sort(V.begin(), V.end());
-    V.erase(std::unique(V.begin(), V.end()), V.end());
-  }
-
   StringPoolSize = Off;
   return Ret;
 }