Bug#20636124 CRASH AFTER NODES POWER OFF CAUSED A SEGFAULT IN GLOBALDICTCACHE

Only use C++ ABI functionality if libstdc++ is being linked. Otherwise resort to protect the allocation/deallocation of the static objects using the existing connection mutex.

Author: Martin Sköld

storage/ndb/src/ndbapi/DictCache.cpp

@@ -21,11 +21,15 @@
 #include <NdbTick.h>
 #include <NdbCondition.h>
 #include <NdbSleep.h>
-#include <my_pthread.h>
 
 static NdbTableImpl * f_invalid_table = 0;
 static NdbTableImpl * f_altered_table = 0;
 
+// If we are linked with libstdc++ then thread safe
+// initialization of the shared table objects can be simplified
+#if HAVE_CXXABI_H
+#include <my_pthread.h>
+
 static my_pthread_once_t once_control = MY_PTHREAD_ONCE_INIT;
 
 void init_static_variables( void )
@@ -35,6 +39,10 @@ void init_static_variables( void )
  f_invalid_table = &_invalid_table;
  f_altered_table = &_altered_table;
 }
+#else
+extern NdbMutex *g_ndb_connection_mutex;
+static int ndb_dict_cache_count = 0;
+#endif // HAVE_CXXABI_H
 
 Ndb_local_table_info *
 Ndb_local_table_info::create(NdbTableImpl *table_impl, Uint32 sz)
@@ -105,14 +113,41 @@ LocalDictCache::drop(const char * name){
 GlobalDictCache::GlobalDictCache(){
  DBUG_ENTER("GlobalDictCache::GlobalDictCache");
  // Initialize static variables
+#if HAVE_CXXABI_H
  my_pthread_once(&once_control, init_static_variables);
+#else
+ NdbMutex_Lock(g_ndb_connection_mutex);
+ if (f_invalid_table == NULL)
+ f_invalid_table = new NdbTableImpl();
+ if (f_altered_table == NULL)
+ f_altered_table = new NdbTableImpl();
+ ndb_dict_cache_count++;
+ NdbMutex_Unlock(g_ndb_connection_mutex);
+#endif HAVE_CXXABI_H
  m_tableHash.createHashTable();
  m_waitForTableCondition = NdbCondition_Create();
  DBUG_VOID_RETURN;
 }
 
 GlobalDictCache::~GlobalDictCache(){
  DBUG_ENTER("GlobalDictCache::~GlobalDictCache");
+#if !HAVE_CXXABI_H
+ NdbMutex_Lock(g_ndb_connection_mutex);
+ if (--ndb_dict_cache_count == 0)
+ {
+ if (f_invalid_table)
+ {
+ delete f_invalid_table;
+ f_invalid_table = 0;
+ }
+ if (f_altered_table)
+ {
+ delete f_altered_table;
+ f_altered_table = 0;
+ }
+ }
+ NdbMutex_Unlock(g_ndb_connection_mutex);
+#endif // !HAVE_CXXABI_H
  NdbElement_t<Vector<TableVersion> > * curr = m_tableHash.getNext(0);
  while(curr != 0){
  Vector<TableVersion> * vers = curr->theData;