Use a std::string rather than a dynamically allocated char* buffer.

This affords us to use std::string's allocation routines and use the destructor
for the memory management. Switching to that also means that we can use
operator==(const std::string&, const char *) to perform the string comparison
rather than resorting to libc functionality (i.e. strcmp).

Patch by Saleem Abdulrasool!

Differential Revision: http://llvm-reviews.chandlerc.com/D230

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171042 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/ARMConstantPoolValue.h b/lib/Target/ARM/ARMConstantPoolValue.h
index ae531c4..93812fe 100644
--- a/lib/Target/ARM/ARMConstantPoolValue.h
+++ b/lib/Target/ARM/ARMConstantPoolValue.h
@@ -161,19 +161,17 @@
 /// ARMConstantPoolSymbol - ARM-specific constantpool values for external
 /// symbols.
 class ARMConstantPoolSymbol : public ARMConstantPoolValue {
-  const char *S;                // ExtSymbol being loaded.
+  const std::string S;          // ExtSymbol being loaded.
 
   ARMConstantPoolSymbol(LLVMContext &C, const char *s, unsigned id,
                         unsigned char PCAdj, ARMCP::ARMCPModifier Modifier,
                         bool AddCurrentAddress);
 
 public:
-  ~ARMConstantPoolSymbol();
-
   static ARMConstantPoolSymbol *Create(LLVMContext &C, const char *s,
                                        unsigned ID, unsigned char PCAdj);
 
-  const char *getSymbol() const { return S; }
+  const char *getSymbol() const { return S.c_str(); }
 
   virtual int getExistingMachineCPValue(MachineConstantPool *CP,
                                         unsigned Alignment);