Fixed memory management issues introduced by revision 157507.

A local std::string was being filled in and then the function would return "s.c_str()".
A local StreamString (which contains a std::string) was being filled in, and essentially also returning the c string from the std::string, though it was in a the StreamString class.

The fix was to not do this by passing a stream object into StringList::Join() and fix the "arch_helper()" function to do what it should: cache the result in a global.

llvm-svn: 157519

lldb/include/lldb/Core/StringList.h

@@ -51,8 +51,8 @@ public:
     const char *
     GetStringAtIndex (size_t idx) const;
 
-    const char *
-    Join (const char *seperator);
+    void
+    Join (const char *separator, Stream &strm);
 
     void
     Clear ();

lldb/source/Core/StringList.cpp

@@ -95,23 +95,20 @@ StringList::GetStringAtIndex (size_t idx) const
     return NULL;
 }
 
-const char *
-StringList::Join (const char *separator)
+void
+StringList::Join (const char *separator, Stream &strm)
 {
     uint32_t size = GetSize();
+    
     if (size == 0)
-        return "";
-    if (size == 1)
-        return GetStringAtIndex(0);
-
-    std::string buf;
+        return;
+    
     for (uint32_t i = 0; i < size; ++i)
     {
         if (i > 0)
-            buf.append(separator);
-        buf.append(GetStringAtIndex(i));
+            strm.PutCString(separator);
+        strm.PutCString(GetStringAtIndex(i));
     }
-    return buf.c_str();;
 }
 
 void

lldb/source/Interpreter/CommandObject.cpp

@@ -849,12 +849,15 @@ CommandObject::GetArgumentDescriptionAsCString (const lldb::CommandArgumentType
 static
 const char *arch_helper()
 {
-    StringList archs;
-    ArchSpec::AutoComplete(NULL, archs);
-    StreamString ss;
-    ss.Printf("These are the supported architecture names:\n");
-    ss.Printf("%s\n", archs.Join("\n"));
-    return ss.GetData();
+    static StreamString g_archs_help;
+    if (g_archs_help.GetData() == NULL)
+    {
+        StringList archs;
+        ArchSpec::AutoComplete(NULL, archs);
+        g_archs_help.Printf("These are the supported architecture names:\n");
+        archs.Join("%s\n", g_archs_help);
+    }
+    return g_archs_help.GetData();
 }
 
 CommandObject::ArgumentTableEntry