3 files changed, 38 insertions, 7 deletions

diff --git a/lib/MC/MCParser/AsmParser.cpp b/lib/MC/MCParser/AsmParser.cpp
index bd5956f..ab5ddaf 100644
--- a/lib/MC/MCParser/AsmParser.cpp
+++ b/lib/MC/MCParser/AsmParser.cpp
@@ -1528,6 +1528,11 @@ bool AsmParser::HandleMacroEntry(StringRef Name, SMLoc NameLoc,
     }
     Lex();
   }
+  // If there weren't any arguments, erase the token vector so everything
+  // else knows that. Leaving around the vestigal empty token list confuses
+  // things.
+  if (MacroArguments.size() == 1 && MacroArguments.back().empty())
+    MacroArguments.clear();
 
   // Macro instantiation is lexical, unfortunately. We construct a new buffer
   // to hold the macro body with substitutions.
@@ -1624,6 +1629,8 @@ bool AsmParser::ParseAssignment(StringRef Name, bool allow_redef) {
       return Error(EqualLoc, "Recursive use of '" + Name + "'");
     else if (Sym->isUndefined() && !Sym->isUsed() && !Sym->isVariable())
       ; // Allow redefinitions of undefined symbols only used in directives.
+    else if (Sym->isVariable() && !Sym->isUsed() && allow_redef)
+      ; // Allow redefinitions of variables that haven't yet been used.
     else if (!Sym->isUndefined() && (!Sym->isVariable() || !allow_redef))
       return Error(EqualLoc, "redefinition of '" + Name + "'");
     else if (!Sym->isVariable())
diff --git a/lib/MC/MCSymbol.cpp b/lib/MC/MCSymbol.cpp
index c2fad167..e013e77 100644
--- a/lib/MC/MCSymbol.cpp
+++ b/lib/MC/MCSymbol.cpp
@@ -54,17 +54,14 @@ const MCSymbol &MCSymbol::AliasedSymbol() const {
 void MCSymbol::setVariableValue(const MCExpr *Value) {
   assert(!IsUsed && "Cannot set a variable that has already been used.");
   assert(Value && "Invalid variable value!");
-  assert((isUndefined() || (isAbsolute() && isa<MCConstantExpr>(Value))) &&
-         "Invalid redefinition!");
   this->Value = Value;
 
   // Variables should always be marked as in the same "section" as the value.
   const MCSection *Section = Value->FindAssociatedSection();
-  if (Section) {
+  if (Section)
     setSection(*Section);
-  } else {
+  else
     setUndefined();
-  }
 }
 
 void MCSymbol::print(raw_ostream &OS) const {
diff --git a/lib/MC/WinCOFFObjectWriter.cpp b/lib/MC/WinCOFFObjectWriter.cpp
index 7144e68..f706cac 100644
--- a/lib/MC/WinCOFFObjectWriter.cpp
+++ b/lib/MC/WinCOFFObjectWriter.cpp
@@ -783,9 +783,22 @@ void WinCOFFObjectWriter::WriteObject(MCAssembler &Asm,
     }
 
     if (Sec->Relocations.size() > 0) {
-      Sec->Header.NumberOfRelocations = Sec->Relocations.size();
+      bool RelocationsOverflow = Sec->Relocations.size() >= 0xffff;
+
+      if (RelocationsOverflow) {
+        // Signal overflow by setting NumberOfSections to max value. Actual
+        // size is found in reloc #0. Microsoft tools understand this.
+        Sec->Header.NumberOfRelocations = 0xffff;
+      } else {
+        Sec->Header.NumberOfRelocations = Sec->Relocations.size();
+      }
       Sec->Header.PointerToRelocations = offset;
 
+      if (RelocationsOverflow) {
+        // Reloc #0 will contain actual count, so make room for it.
+        offset += COFF::RelocationSize;
+      }
+
       offset += COFF::RelocationSize * Sec->Relocations.size();
 
       for (relocations::iterator cr = Sec->Relocations.begin(),
@@ -820,8 +833,12 @@ void WinCOFFObjectWriter::WriteObject(MCAssembler &Asm,
     MCAssembler::const_iterator j, je;
 
     for (i = Sections.begin(), ie = Sections.end(); i != ie; i++)
-      if ((*i)->Number != -1)
+      if ((*i)->Number != -1) {
+        if ((*i)->Relocations.size() >= 0xffff) {
+          (*i)->Header.Characteristics |= COFF::IMAGE_SCN_LNK_NRELOC_OVFL;
+        }
         WriteSectionHeader((*i)->Header);
+      }
 
     for (i = Sections.begin(), ie = Sections.end(),
          j = Asm.begin(), je = Asm.end();
@@ -841,6 +858,16 @@ void WinCOFFObjectWriter::WriteObject(MCAssembler &Asm,
         assert(OS.tell() == (*i)->Header.PointerToRelocations &&
                "Section::PointerToRelocations is insane!");
 
+        if ((*i)->Relocations.size() >= 0xffff) {
+          // In case of overflow, write actual relocation count as first
+          // relocation. Including the synthetic reloc itself (+ 1).
+          COFF::relocation r;
+          r.VirtualAddress = (*i)->Relocations.size() + 1;
+          r.SymbolTableIndex = 0;
+          r.Type = 0;
+          WriteRelocation(r);
+        }
+
         for (relocations::const_iterator k = (*i)->Relocations.begin(),
                                                ke = (*i)->Relocations.end();
                                                k != ke; k++) {