2127258 - FP lookup table inconsistency & Memory corruption in IQ16 SP8.x

Suddenly IQ became crash during a delete operation. After the problem was detected, customer checked the consistency of the table which was to be deleted 
  via sp_iqcheckdb with check mode and  found inconsistency in the table. Customer tried to rebuild these 2 inconsistent FP indexes by running sp_iqrebuildindex and succeeded.
After rebuilding these problematic FP indexes, no more errors reported by rerunning sp_iqcheckdb.
Customer succeeded to execute the delete operation which had made IQ server to crash.

   [ Imqsg & stack ]  
      I. 02/02 13:16:36. 0001073510 IQ Internal Error Detected:  Memory Corruption
      ...
      I. 02/02 13:16:36. 0001073510 ***   SAP IQ Abort:
      I. 02/02 13:16:36. 0001073510 ***      From:  oslib/hos_mem.cxx:259
      ...
      I. 02/02 13:39:23. 0000000014 DBCC: ERROR - Byte FP lookup table inconsistency, lookupCount[0]=832441110 <> barrayCount=832359189.
      ...
      I. 02/02 13:39:23. 0000000014 DBCC: Statistics check detected exception from  INDEX { sta_admin.TWJHC201.ASIQ_IDX_T1005_C3_FP }

      I. 02/02 13:26:55. 0001073510     ***************** This is the STACKTRACE ***************     
      ===== Thread Number  1299  (IQ connID: 0001073510) =====
      ... hos_ABORTPKcjRK13hos_exceptionPcS4_ + 0x520 at oslib/hos_abrt.cxx:284   ...
      ... ThrowRK13hos_exception + 0x140 at oslib/hos_throw.cxx:131   ...
      ... hos_mem10TestFencesEv at oslib/hos_mem.cxx:251
      ... hos_mem19CheckFencesAndThrowEv + 0x110 at oslib/hos_mem.cxx:256   ...
      ... hos_memmgr10FreeHosMemEPv + 0x80 at oslib/hos_mem.cxx:391   ...
      ... Pv at oslib/hos_mem.cxx:639
      ... aPv + 0x50 at oslib/hos_mem.cxx:627   ...
      ... s_lookupContextD1Ev + 0x50 at slib/s_dpidxfetch.cxx:2493   ...
      ... hs_dp10DeleteNBitEPK4s_bmi + 0x380 at slib/s_dpidx.cxx:1840   ...
      ...

SAP IQ 16.0 SP08.x

KBA , BC-SYB-IQ , Sybase IQ , Problem