Add a virtual destructor to a class with virtual methods.

[krasin]

Summary

Recently, Clang enabled the check for virtual destructors
in the presence of virtual methods. That broke the bootstrap
build. Fixing it.

This is a second attempt to fix this. Now, with out-of-line definition.

[pcc]

LGTM

If this doesn't work I guess you can also try overriding operator delete for this class.

[krasin]

So, this does not work as it introduces an undefined reference to the operator delete. And after a second thought, it might be that it's the warning that got enabled by default is to blame.

lib/sanitizer_common/sanitizer_flag_parser.h

 #include "sanitizer_internal_defs.h"
 #include "sanitizer_libc.h"
 #include "sanitizer_common.h"
 
 namespace __sanitizer {
 
 class FlagHandlerBase {
  public:
+  virtual ~FlagHandlerBase();
   virtual bool Parse(const char *value) { return false; }
 };
 
 template <typename T>
 class FlagHandler : public FlagHandlerBase {
   T *t_;
 
  public:

lib/sanitizer_common/sanitizer_flag_parser.cc

 
 #include "sanitizer_common.h"
 #include "sanitizer_libc.h"
 #include "sanitizer_flags.h"
 #include "sanitizer_flag_parser.h"
 
 namespace __sanitizer {
 
+FlagHandlerBase::~FlagHandlerBase() {}
+
 LowLevelAllocator FlagParser::Alloc;
 
 class UnknownFlags {
   static const int kMaxUnknownFlags = 20;
   const char *unknown_flags_[kMaxUnknownFlags];
   int n_unknown_flags_;
 
  public: