llvm-mc: Diagnose misuse (mix) of defined symbols and labels.

 - For example, we diagnose errors on:
--
a:
a = 10
--

 - For now we reject code like:
--
.long a
a = 10
--
   which "as" accepts (on Darwin).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74476 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 7 insertions, 1 deletions

diff --git a/include/llvm/MC/MCContext.h b/include/llvm/MC/MCContext.h
index 13180e8..846e195 100644
--- a/include/llvm/MC/MCContext.h
+++ b/include/llvm/MC/MCContext.h
@@ -31,6 +31,8 @@ namespace llvm {
     StringMap<MCSymbol*> Symbols;
 
     /// SymbolValues - Bindings of symbols to values.
+    //
+    // FIXME: Is there a good reason to not just put this in the MCSymbol?
     DenseMap<MCSymbol*, MCValue> SymbolValues;
 
     /// Allocator - Allocator object used for creating machine code objects.
diff --git a/include/llvm/MC/MCSymbol.h b/include/llvm/MC/MCSymbol.h
index 06f50ae..fcfc9d6 100644
--- a/include/llvm/MC/MCSymbol.h
+++ b/include/llvm/MC/MCSymbol.h
@@ -17,14 +17,18 @@ namespace llvm {
     MCSection *Section;
     std::string Name;
     unsigned IsTemporary : 1;
+    unsigned IsExternal : 1;
 
   public:
     MCSymbol(const char *_Name, bool _IsTemporary) 
-      : Section(0), Name(_Name), IsTemporary(_IsTemporary) {}
+      : Section(0), Name(_Name), IsTemporary(_IsTemporary), IsExternal(false) {}
 
     MCSection *getSection() const { return Section; }
     void setSection(MCSection *Value) { Section = Value; }
 
+    bool isExternal() const { return IsExternal; }
+    void setExternal(bool Value) { IsExternal = Value; }
+
     const std::string &getName() const { return Name; }
   };