[lldb] Fix RichManglingContext::FromCxxMethodName() leak

`RichManglingContext::FromCxxMethodName` allocates a m_cxx_method_parser, but never deletes it.

This fixes a `-DLLVM_USE_SANITIZER=Leaks` failure.

Reviewed By: teemperor

Differential Revision: https://reviews.llvm.org/D100795

lldb/include/lldb/Core/RichManglingContext.h

@@ -29,7 +29,7 @@ public:
     m_ipd_buf[0] = '\0';
   }
 
-  ~RichManglingContext() { std::free(m_ipd_buf); }
+  ~RichManglingContext();
 
   /// Use the ItaniumPartialDemangler to obtain rich mangling information from
   /// the given mangled name.
@@ -77,6 +77,9 @@ private:
 
   /// Members for ItaniumPartialDemangler
   llvm::ItaniumPartialDemangler m_ipd;
+  /// Note: m_ipd_buf is a raw pointer due to being resized by realloc via
+  /// ItaniumPartialDemangler. It should be managed with malloc/free, not
+  /// new/delete.
   char *m_ipd_buf;
   size_t m_ipd_buf_size;
 
@@ -86,6 +89,9 @@ private:
   /// dependency. Instead keep a llvm::Any and cast it on-access in the cpp.
   llvm::Any m_cxx_method_parser;
 
+  /// Clean up memory when using PluginCxxLanguage
+  void ResetCxxMethodParser();
+
   /// Clean up memory and set a new info provider for this instance.
   void ResetProvider(InfoProvider new_provider);
 

lldb/source/Core/RichManglingContext.cpp

@@ -19,7 +19,12 @@ using namespace lldb;
 using namespace lldb_private;
 
 // RichManglingContext
-void RichManglingContext::ResetProvider(InfoProvider new_provider) {
+RichManglingContext::~RichManglingContext() {
+  std::free(m_ipd_buf);
+  ResetCxxMethodParser();
+}
+
+void RichManglingContext::ResetCxxMethodParser() {
   // If we want to support parsers for other languages some day, we need a
   // switch here to delete the correct parser type.
   if (m_cxx_method_parser.hasValue()) {
@@ -27,6 +32,10 @@ void RichManglingContext::ResetProvider(InfoProvider new_provider) {
     delete get<CPlusPlusLanguage::MethodName>(m_cxx_method_parser);
     m_cxx_method_parser.reset();
   }
+}
+
+void RichManglingContext::ResetProvider(InfoProvider new_provider) {
+  ResetCxxMethodParser();
 
   assert(new_provider != None && "Only reset to a valid provider");
   m_provider = new_provider;