[lld] r251789 - [ELF2] Ensure that .dynsym section is finalized before .gnu.hash.

[Igor Kudrin via llvm-commits]

Author: ikudrin
Date: Mon Nov  2 04:46:14 2015
New Revision: 251789

URL: http://llvm.org/viewvc/llvm-project?rev=251789&view=rev
Log:
[ELF2] Ensure that .dynsym section is finalized before .gnu.hash.

It is required to fill up the GNU hash table section before its
finalize() method is called.

Differential Revision: http://reviews.llvm.org/D14196

Modified:
    lld/trunk/ELF/OutputSections.cpp
    lld/trunk/ELF/Writer.cpp

Modified: lld/trunk/ELF/OutputSections.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/OutputSections.cpp?rev=251789&r1=251788&r2=251789&view=diff
==============================================================================
--- lld/trunk/ELF/OutputSections.cpp (original)
+++ lld/trunk/ELF/OutputSections.cpp Mon Nov  2 04:46:14 2015
@@ -340,8 +340,7 @@ unsigned GnuHashTableSection<ELFT>::calc
 }
 
 template <class ELFT> void GnuHashTableSection<ELFT>::finalize() {
-  ArrayRef<SymbolBody *> A = Out<ELFT>::DynSymTab->getSymbols();
-  unsigned NumHashed = std::count_if(A.begin(), A.end(), includeInGnuHashTable);
+  unsigned NumHashed = HashedSymbols.size();
   NBuckets = calcNBuckets(NumHashed);
   MaskWords = calcMaskWords(NumHashed);
   // Second hash shift estimation: just predefined values.
@@ -900,6 +899,9 @@ SymbolTableSection<ELFT>::SymbolTableSec
 }
 
 template <class ELFT> void SymbolTableSection<ELFT>::finalize() {
+  if (this->Header.sh_size)
+    return; // Already finalized.
+
   this->Header.sh_size = getNumSymbols() * sizeof(Elf_Sym);
   this->Header.sh_link = StrTabSec.SectionIndex;
   this->Header.sh_info = NumLocals + 1;

Modified: lld/trunk/ELF/Writer.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/Writer.cpp?rev=251789&r1=251788&r2=251789&view=diff
==============================================================================
--- lld/trunk/ELF/Writer.cpp (original)
+++ lld/trunk/ELF/Writer.cpp Mon Nov  2 04:46:14 2015
@@ -581,9 +581,13 @@ template <class ELFT> void Writer<ELFT>:
   for (OutputSectionBase<ELFT> *Sec : OutputSections)
     Out<ELFT>::ShStrTab->add(Sec->getName());
 
-  // Fill the DynStrTab early because Dynamic adds strings to
-  // DynStrTab but .dynstr may appear before .dynamic.
+  // Finalizers fix each section's size.
+  // .dynamic section's finalizer may add strings to .dynstr,
+  // so finalize that early.
+  // Likewise, .dynsym is finalized early since that may fill up .gnu.hash.
   Out<ELFT>::Dynamic->finalize();
+  if (isOutputDynamic())
+    Out<ELFT>::DynSymTab->finalize();
 
   // Fill other section headers.
   for (OutputSectionBase<ELFT> *Sec : OutputSections)