[RTEMS Project] #3755: leak in realloc

[RTEMS trac]

#3755: leak in realloc
---------------------------+--------------------------
  Reporter:  Jeffrey Hill  |      Owner:  (none)
      Type:  defect        |     Status:  new
  Priority:  normal        |  Milestone:
 Component:  admin         |    Version:  4.11
  Severity:  normal        |   Keywords:  realloc leak
Blocked By:                |   Blocking:
---------------------------+--------------------------
 We are running Lua in an RTEMS system which, by default, uses realloc for
 memory allocation. We observe a memory leak on RTEMS unless we replace the
 default Lua allocator on RTEMS as follows. The net result being avoidance
 of any calls to realloc, and instead fall back to Lua memory allocation
 based solely on malloc and free.

 nios2-rtems4.11-gcc (GCC) 4.9.3 20150626 (RTEMS 4.11, RSB no-repo, Newlib
 2.2.0.20150423)

 configure --target=nios2-rtems4.11 --prefix=/ade/rtems/install/rtems-4-11
 --disable-itron --disable-tests --enable-posix --enable-cxx --enable-
 rtemsbsp=altera-sys-config-S43X-TDAQ-dev --enable-networking

 This is occurring in 4.11.1.99. We definitely need to sync up, however our
 cursory search in the bug database indicated that this might need to be
 reported.

 {{{
 #if defined ( CAS_LUA_DONT_USE_REALLOC )
 #pragma message("installing RTEMS workaround for realloc bugs")
 void * RspThr :: LuaHandle :: m_alloc ( void * const pPriv, void * const
 pOld,
                                     const size_t osize, const size_t nsize
 )
 {
     void * pNew;
     if ( nsize > 0u ) {
         if ( pOld ) {
             if ( osize == nsize ) {
                 pNew = pOld;
             }
             else {
                 pNew = malloc ( nsize );
                 if ( pNew ) {
                     memcpy ( pNew, pOld, std :: min ( osize, nsize ) );
                     free ( pOld );
                 }
             }
         }
         else {
             pNew = malloc ( nsize );
         }
     }
     else {
         free ( pOld );
         pNew = NULL;
     }
     return pNew;
 }
 #else
 void * RspThr :: LuaHandle :: m_alloc ( void * const pPriv, void * const
 pOld,
                                 const size_t osize, const size_t nsize )
 {
     if ( nsize == 0 ) {
         free ( pOld );
         return NULL;
     }
     else {
         void * const pNew = realloc ( pOld, nsize );
         return pNew;
     }
 }
 #endif /* ifdef CAS_LUA_DONT_USE_REALLOC */
 }}}

--
Ticket URL: <http://devel.rtems.org/ticket/3755>
RTEMS Project <http://www.rtems.org/>
RTEMS Project