Changes in libcfa/src/heap.cfa [1aa6ecb:baf608a]

File:

• libcfa/src/heap.cfa (modified) (41 diffs)

libcfa/src/heap.cfa

@@ -10 +10 @@
 // Created On       : Tue Dec 19 21:58:35 2017
 // Last Modified By : Peter A. Buhr
-// Last Modified On : Fri Oct 18 07:42:09 2019
-// Update Count     : 556
+// Last Modified On : Wed Dec  4 21:42:46 2019
+// Update Count     : 646
 //
 
@@ -18 +18 @@
 #include <stdio.h>                                                                              // snprintf, fileno
 #include <errno.h>                                                                              // errno
+#include <string.h>                                                                             // memset, memcpy
 extern "C" {
 #include <sys/mman.h>                                                                   // mmap, munmap
@@ -27 +28 @@
 #include "bits/locks.hfa"                                                               // __spinlock_t
 #include "startup.hfa"                                                                  // STARTUP_PRIORITY_MEMORY
-#include "stdlib.hfa"                                                                   // bsearchl
+//#include "stdlib.hfa"                                                                 // bsearchl
 #include "malloc.h"
 
+#define MIN(x, y) (y > x ? x : y)
 
 static bool traceHeap = false;
 
-inline bool traceHeap() {
-        return traceHeap;
-} // traceHeap
+inline bool traceHeap() { return traceHeap; }
 
 bool traceHeapOn() {
@@ -49 +49 @@
 } // traceHeapOff
 
-
-static bool checkFree = false;
-
-inline bool checkFree() {
-        return checkFree;
-} // checkFree
-
-bool checkFreeOn() {
-        bool temp = checkFree;
-        checkFree = true;
+bool traceHeapTerm() { return false; }
+
+
+static bool prtFree = false;
+
+inline bool prtFree() {
+        return prtFree;
+} // prtFree
+
+bool prtFreeOn() {
+        bool temp = prtFree;
+        prtFree = true;
         return temp;
-} // checkFreeOn
-
-bool checkFreeOff() {
-        bool temp = checkFree;
-        checkFree = false;
+} // prtFreeOn
+
+bool prtFreeOff() {
+        bool temp = prtFree;
+        prtFree = false;
         return temp;
-} // checkFreeOff
-
-
-// static bool traceHeapTerm = false;
-
-// inline bool traceHeapTerm() {
-//      return traceHeapTerm;
-// } // traceHeapTerm
-
-// bool traceHeapTermOn() {
-//      bool temp = traceHeapTerm;
-//      traceHeapTerm = true;
-//      return temp;
-// } // traceHeapTermOn
-
-// bool traceHeapTermOff() {
-//      bool temp = traceHeapTerm;
-//      traceHeapTerm = false;
-//      return temp;
-// } // traceHeapTermOff
+} // prtFreeOff
 
 
 enum {
+        // Define the default extension heap amount in units of bytes. When the uC++ supplied heap reaches the brk address,
+        // the brk address is extended by the extension amount.
+        __CFA_DEFAULT_HEAP_EXPANSION__ = (1 * 1024 * 1024),
+
+        // Define the mmap crossover point during allocation. Allocations less than this amount are allocated from buckets;
+        // values greater than or equal to this value are mmap from the operating system.
         __CFA_DEFAULT_MMAP_START__ = (512 * 1024 + 1),
-        __CFA_DEFAULT_HEAP_EXPANSION__ = (1 * 1024 * 1024),
 };
 
@@ -105 +93 @@
 static unsigned int allocFree;                                                  // running total of allocations minus frees
 
-static void checkUnfreed() {
+static void prtUnfreed() {
         if ( allocFree != 0 ) {
                 // DO NOT USE STREAMS AS THEY MAY BE UNAVAILABLE AT THIS POINT.
-                // char helpText[512];
-                // int len = snprintf( helpText, sizeof(helpText), "CFA warning (UNIX pid:%ld) : program terminating with %u(0x%x) bytes of storage allocated but not freed.\n"
-                //                                      "Possible cause is unfreed storage allocated by the program or system/library routines called from the program.\n",
-                //                                      (long int)getpid(), allocFree, allocFree ); // always print the UNIX pid
-                // __cfaabi_dbg_bits_write( helpText, len );
-        } // if
-} // checkUnfreed
+                char helpText[512];
+                int len = snprintf( helpText, sizeof(helpText), "CFA warning (UNIX pid:%ld) : program terminating with %u(0x%x) bytes of storage allocated but not freed.\n"
+                                                        "Possible cause is unfreed storage allocated by the program or system/library routines called from the program.\n",
+                                                        (long int)getpid(), allocFree, allocFree ); // always print the UNIX pid
+                __cfaabi_bits_write( STDERR_FILENO, helpText, len ); // print debug/nodebug
+        } // if
+} // prtUnfreed
 
 extern "C" {
@@ -123 +111 @@
         void heapAppStop() {                                                            // called by __cfaabi_appready_startdown
                 fclose( stdin ); fclose( stdout );
-                checkUnfreed();
+                prtUnfreed();
         } // heapAppStop
 } // extern "C"
 #endif // __CFA_DEBUG__
+
 
 // statically allocated variables => zero filled.
@@ -134 +123 @@
 static unsigned int maxBucketsUsed;                                             // maximum number of buckets in use
 
-
-// #comment TD : This defined is significantly different from the __ALIGN__ define from locks.hfa
-#define ALIGN 16
 
 #define SPINLOCK 0
@@ -147 +133 @@
 // Recursive definitions: HeapManager needs size of bucket array and bucket area needs sizeof HeapManager storage.
 // Break recusion by hardcoding number of buckets and statically checking number is correct after bucket array defined.
-enum { NoBucketSizes = 93 };                                                    // number of buckets sizes
+enum { NoBucketSizes = 91 };                                                    // number of buckets sizes
 
 struct HeapManager {
@@ -194 +180 @@
                         } kind; // Kind
                 } header; // Header
-                char pad[ALIGN - sizeof( Header )];
+                char pad[libAlign() - sizeof( Header )];
                 char data[0];                                                                   // storage
         }; // Storage
 
-        static_assert( ALIGN >= sizeof( Storage ), "ALIGN < sizeof( Storage )" );
+        static_assert( libAlign() >= sizeof( Storage ), "libAlign() < sizeof( Storage )" );
 
         struct FreeHeader {
@@ -228 +214 @@
 #define __STATISTICS__
 
+// Bucket size must be multiple of 16.
 // Powers of 2 are common allocation sizes, so make powers of 2 generate the minimum required size.
 static const unsigned int bucketSizes[] @= {                    // different bucket sizes
-        16, 32, 48, 64,
-        64 + sizeof(HeapManager.Storage), 96, 112, 128, 128 + sizeof(HeapManager.Storage), 160, 192, 224,
-        256 + sizeof(HeapManager.Storage), 320, 384, 448, 512 + sizeof(HeapManager.Storage), 640, 768, 896,
-        1_024 + sizeof(HeapManager.Storage), 1_536, 2_048 + sizeof(HeapManager.Storage), 2_560, 3_072, 3_584, 4_096 + sizeof(HeapManager.Storage), 6_144,
-        8_192 + sizeof(HeapManager.Storage), 9_216, 10_240, 11_264, 12_288, 13_312, 14_336, 15_360,
-        16_384 + sizeof(HeapManager.Storage), 18_432, 20_480, 22_528, 24_576, 26_624, 28_672, 30_720,
-        32_768 + sizeof(HeapManager.Storage), 36_864, 40_960, 45_056, 49_152, 53_248, 57_344, 61_440,
-        65_536 + sizeof(HeapManager.Storage), 73_728, 81_920, 90_112, 98_304, 106_496, 114_688, 122_880,
-        131_072 + sizeof(HeapManager.Storage), 147_456, 163_840, 180_224, 196_608, 212_992, 229_376, 245_760,
-        262_144 + sizeof(HeapManager.Storage), 294_912, 327_680, 360_448, 393_216, 425_984, 458_752, 491_520,
-        524_288 + sizeof(HeapManager.Storage), 655_360, 786_432, 917_504, 1_048_576 + sizeof(HeapManager.Storage), 1_179_648, 1_310_720, 1_441_792,
-        1_572_864, 1_703_936, 1_835_008, 1_966_080, 2_097_152 + sizeof(HeapManager.Storage), 2_621_440, 3_145_728, 3_670_016,
-        4_194_304 + sizeof(HeapManager.Storage)
+        16, 32, 48, 64 + sizeof(HeapManager.Storage), // 4
+        96, 112, 128 + sizeof(HeapManager.Storage), // 3
+        160, 192, 224, 256 + sizeof(HeapManager.Storage), // 4
+        320, 384, 448, 512 + sizeof(HeapManager.Storage), // 4
+        640, 768, 896, 1_024 + sizeof(HeapManager.Storage), // 4
+        1_536, 2_048 + sizeof(HeapManager.Storage), // 2
+        2_560, 3_072, 3_584, 4_096 + sizeof(HeapManager.Storage), // 4
+        6_144, 8_192 + sizeof(HeapManager.Storage), // 2
+        9_216, 10_240, 11_264, 12_288, 13_312, 14_336, 15_360, 16_384 + sizeof(HeapManager.Storage), // 8
+        18_432, 20_480, 22_528, 24_576, 26_624, 28_672, 30_720, 32_768 + sizeof(HeapManager.Storage), // 8
+        36_864, 40_960, 45_056, 49_152, 53_248, 57_344, 61_440, 65_536 + sizeof(HeapManager.Storage), // 8
+        73_728, 81_920, 90_112, 98_304, 106_496, 114_688, 122_880, 131_072 + sizeof(HeapManager.Storage), // 8
+        147_456, 163_840, 180_224, 196_608, 212_992, 229_376, 245_760, 262_144 + sizeof(HeapManager.Storage), // 8
+        294_912, 327_680, 360_448, 393_216, 425_984, 458_752, 491_520, 524_288 + sizeof(HeapManager.Storage), // 8
+        655_360, 786_432, 917_504, 1_048_576 + sizeof(HeapManager.Storage), // 4
+        1_179_648, 1_310_720, 1_441_792, 1_572_864, 1_703_936, 1_835_008, 1_966_080, 2_097_152 + sizeof(HeapManager.Storage), // 8
+        2_621_440, 3_145_728, 3_670_016, 4_194_304 + sizeof(HeapManager.Storage), // 4
 };
 
@@ -251 +242 @@
 static unsigned char lookup[LookupSizes];                               // O(1) lookup for small sizes
 #endif // FASTLOOKUP
+
 static int mmapFd = -1;                                                                 // fake or actual fd for anonymous file
-
-
 #ifdef __CFA_DEBUG__
 static bool heapBoot = 0;                                                               // detect recursion during boot
@@ -259 +249 @@
 static HeapManager heapManager __attribute__(( aligned (128) )) @= {}; // size of cache line to prevent false sharing
 
-// #comment TD : The return type of this function should be commented
-static inline bool setMmapStart( size_t value ) {
-  if ( value < pageSize || bucketSizes[NoBucketSizes - 1] < value ) return true;
-        mmapStart = value;                                                                      // set global
-
-        // find the closest bucket size less than or equal to the mmapStart size
-        maxBucketsUsed = bsearchl( (unsigned int)mmapStart, bucketSizes, NoBucketSizes ); // binary search
-        assert( maxBucketsUsed < NoBucketSizes );                       // subscript failure ?
-        assert( mmapStart <= bucketSizes[maxBucketsUsed] ); // search failure ?
-        return false;
-} // setMmapStart
-
-
-static void ?{}( HeapManager & manager ) with ( manager ) {
-        pageSize = sysconf( _SC_PAGESIZE );
-
-        for ( unsigned int i = 0; i < NoBucketSizes; i += 1 ) { // initialize the free lists
-                freeLists[i].blockSize = bucketSizes[i];
-        } // for
-
-        #ifdef FASTLOOKUP
-        unsigned int idx = 0;
-        for ( unsigned int i = 0; i < LookupSizes; i += 1 ) {
-                if ( i > bucketSizes[idx] ) idx += 1;
-                lookup[i] = idx;
-        } // for
-        #endif // FASTLOOKUP
-
-        if ( setMmapStart( default_mmap_start() ) ) {
-                abort( "HeapManager : internal error, mmap start initialization failure." );
-        } // if
-        heapExpand = default_heap_expansion();
-
-        char * End = (char *)sbrk( 0 );
-        sbrk( (char *)libCeiling( (long unsigned int)End, libAlign() ) - End ); // move start of heap to multiple of alignment
-        heapBegin = heapEnd = sbrk( 0 );                                        // get new start point
-} // HeapManager
-
-
-static void ^?{}( HeapManager & ) {
-        #ifdef __STATISTICS__
-        // if ( traceHeapTerm() ) {
-        //      printStats();
-        //      if ( checkfree() ) checkFree( heapManager, true );
-        // } // if
-        #endif // __STATISTICS__
-} // ~HeapManager
-
-
-static void memory_startup( void ) __attribute__(( constructor( STARTUP_PRIORITY_MEMORY ) ));
-void memory_startup( void ) {
-        #ifdef __CFA_DEBUG__
-        if ( unlikely( heapBoot ) ) {                                           // check for recursion during system boot
-                // DO NOT USE STREAMS AS THEY MAY BE UNAVAILABLE AT THIS POINT.
-                abort( "boot() : internal error, recursively invoked during system boot." );
-        } // if
-        heapBoot = true;
-        #endif // __CFA_DEBUG__
-
-        //assert( heapManager.heapBegin != 0 );
-        //heapManager{};
-        if ( heapManager.heapBegin == 0 ) heapManager{};
-} // memory_startup
-
-static void memory_shutdown( void ) __attribute__(( destructor( STARTUP_PRIORITY_MEMORY ) ));
-void memory_shutdown( void ) {
-        ^heapManager{};
-} // memory_shutdown
-
 
 #ifdef __STATISTICS__
-static unsigned long long int mmap_storage;                             // heap statistics counters
+// Heap statistics counters.
+static unsigned long long int mmap_storage;
 static unsigned int mmap_calls;
 static unsigned long long int munmap_storage;
@@ -348 +270 @@
 static unsigned long long int realloc_storage;
 static unsigned int realloc_calls;
-
-static int statfd;                                                                              // statistics file descriptor (changed by malloc_stats_fd)
-
+// Statistics file descriptor (changed by malloc_stats_fd).
+static int statfd = STDERR_FILENO;                                              // default stderr
 
 // Use "write" because streams may be shutdown when calls are made.
 static void printStats() {
         char helpText[512];
-        __cfaabi_dbg_bits_print_buffer( helpText, sizeof(helpText),
+        __cfaabi_bits_print_buffer( STDERR_FILENO, helpText, sizeof(helpText),
                                                                         "\nHeap statistics:\n"
                                                                         "  malloc: calls %u / storage %llu\n"
@@ -405 +326 @@
                                                 sbrk_calls, sbrk_storage
                 );
-        return write( fileno( stream ), helpText, len );        // -1 => error
+        __cfaabi_bits_write( fileno( stream ), helpText, len ); // ensures all bytes written or exit
+        return len;
 } // printStatsXML
 #endif // __STATISTICS__
+
 
 // #comment TD : Is this the samething as Out-of-Memory?
@@ -418 +341 @@
 
 static inline void checkAlign( size_t alignment ) {
-        if ( alignment < sizeof(void *) || ! libPow2( alignment ) ) {
-                abort( "Alignment %zu for memory allocation is less than sizeof(void *) and/or not a power of 2.", alignment );
+        if ( alignment < libAlign() || ! libPow2( alignment ) ) {
+                abort( "Alignment %zu for memory allocation is less than %d and/or not a power of 2.", alignment, libAlign() );
         } // if
 } // checkAlign
@@ -431 +354 @@
 
 
-static inline void checkHeader( bool check, const char * name, void * addr ) {
-        if ( unlikely( check ) ) {                                                      // bad address ?
-                abort( "Attempt to %s storage %p with address outside the heap.\n"
-                           "Possible cause is duplicate free on same block or overwriting of memory.",
-                           name, addr );
-        } // if
-} // checkHeader
-
-// #comment TD : function should be commented and/or have a more evocative name
-//               this isn't either a check or a constructor which is what I would expect this function to be
-static inline void fakeHeader( HeapManager.Storage.Header *& header, size_t & size, size_t & alignment ) {
-        if ( unlikely( (header->kind.fake.alignment & 1) == 1 ) ) { // fake header ?
-                size_t offset = header->kind.fake.offset;
-                alignment = header->kind.fake.alignment & -2;   // remove flag from value
-                #ifdef __CFA_DEBUG__
-                checkAlign( alignment );                                                // check alignment
-                #endif // __CFA_DEBUG__
-                header = (HeapManager.Storage.Header *)((char *)header - offset);
-        } // if
-} // fakeHeader
-
-// #comment TD : Why is this a define
-#define headerAddr( addr ) ((HeapManager.Storage.Header *)( (char *)addr - sizeof(HeapManager.Storage) ))
-
-static inline bool headers( const char * name, void * addr, HeapManager.Storage.Header *& header, HeapManager.FreeHeader *& freeElem, size_t & size, size_t & alignment ) with ( heapManager ) {
-        header = headerAddr( addr );
-
-        if ( unlikely( heapEnd < addr ) ) {                                     // mmapped ?
-                fakeHeader( header, size, alignment );
-                size = header->kind.real.blockSize & -3;                // mmap size
-                return true;
-        } // if
-
-        #ifdef __CFA_DEBUG__
-        checkHeader( addr < heapBegin || header < (HeapManager.Storage.Header *)heapBegin, name, addr ); // bad low address ?
-        #endif // __CFA_DEBUG__
-
-        // #comment TD : This code looks weird...
-        //               It's called as the first statement of both branches of the last if, with the same parameters in all cases
-
-        // header may be safe to dereference
-        fakeHeader( header, size, alignment );
-        #ifdef __CFA_DEBUG__
-        checkHeader( header < (HeapManager.Storage.Header *)heapBegin || (HeapManager.Storage.Header *)heapEnd < header, name, addr ); // bad address ? (offset could be + or -)
-        #endif // __CFA_DEBUG__
-
-        freeElem = (HeapManager.FreeHeader *)((size_t)header->kind.real.home & -3);
-        #ifdef __CFA_DEBUG__
-        if ( freeElem < &freeLists[0] || &freeLists[NoBucketSizes] <= freeElem ) {
-                abort( "Attempt to %s storage %p with corrupted header.\n"
-                           "Possible cause is duplicate free on same block or overwriting of header information.",
-                           name, addr );
-        } // if
-        #endif // __CFA_DEBUG__
-        size = freeElem->blockSize;
-        return false;
-} // headers
-
-
-static inline void * extend( size_t size ) with ( heapManager ) {
-        lock( extlock __cfaabi_dbg_ctx2 );
-        ptrdiff_t rem = heapRemaining - size;
-        if ( rem < 0 ) {
-                // If the size requested is bigger than the current remaining storage, increase the size of the heap.
-
-                size_t increase = libCeiling( size > heapExpand ? size : heapExpand, libAlign() );
-                if ( sbrk( increase ) == (void *)-1 ) {
-                        unlock( extlock );
-                        errno = ENOMEM;
-                        return 0;
-                } // if
-                #ifdef __STATISTICS__
-                sbrk_calls += 1;
-                sbrk_storage += increase;
-                #endif // __STATISTICS__
-                #ifdef __CFA_DEBUG__
-                // Set new memory to garbage so subsequent uninitialized usages might fail.
-                memset( (char *)heapEnd + heapRemaining, '\377', increase );
-                #endif // __CFA_DEBUG__
-                rem = heapRemaining + increase - size;
-        } // if
-
-        HeapManager.Storage * block = (HeapManager.Storage *)heapEnd;
-        heapRemaining = rem;
-        heapEnd = (char *)heapEnd + size;
-        unlock( extlock );
-        return block;
-} // extend
-
-
+// thunk problem
 size_t Bsearchl( unsigned int key, const unsigned int * vals, size_t dim ) {
         size_t l = 0, m, h = dim;
@@ -535 +369 @@
 
 
+static inline bool setMmapStart( size_t value ) {               // true => mmapped, false => sbrk
+  if ( value < pageSize || bucketSizes[NoBucketSizes - 1] < value ) return true;
+        mmapStart = value;                                                                      // set global
+
+        // find the closest bucket size less than or equal to the mmapStart size
+        maxBucketsUsed = Bsearchl( (unsigned int)mmapStart, bucketSizes, NoBucketSizes ); // binary search
+        assert( maxBucketsUsed < NoBucketSizes );                       // subscript failure ?
+        assert( mmapStart <= bucketSizes[maxBucketsUsed] ); // search failure ?
+        return false;
+} // setMmapStart
+
+
+static inline void checkHeader( bool check, const char * name, void * addr ) {
+        if ( unlikely( check ) ) {                                                      // bad address ?
+                abort( "Attempt to %s storage %p with address outside the heap.\n"
+                           "Possible cause is duplicate free on same block or overwriting of memory.",
+                           name, addr );
+        } // if
+} // checkHeader
+
+
+static inline void fakeHeader( HeapManager.Storage.Header *& header, size_t & alignment ) {
+        if ( unlikely( (header->kind.fake.alignment & 1) == 1 ) ) { // fake header ?
+                size_t offset = header->kind.fake.offset;
+                alignment = header->kind.fake.alignment & -2;   // remove flag from value
+                #ifdef __CFA_DEBUG__
+                checkAlign( alignment );                                                // check alignment
+                #endif // __CFA_DEBUG__
+                header = (HeapManager.Storage.Header *)((char *)header - offset);
+        } // if
+} // fakeHeader
+
+
+// <-------+----------------------------------------------------> bsize (bucket size)
+// |header |addr
+//==================================================================================
+//                                | alignment
+// <-----------------<------------+-----------------------------> bsize (bucket size)
+//                   |fake-header | addr
+#define headerAddr( addr ) ((HeapManager.Storage.Header *)( (char *)addr - sizeof(HeapManager.Storage) ))
+
+// <-------<<--------------------- dsize ---------------------->> bsize (bucket size)
+// |header |addr
+//==================================================================================
+//                                | alignment
+// <------------------------------<<---------- dsize --------->>> bsize (bucket size)
+//                   |fake-header |addr
+#define dataStorage( bsize, addr, header ) (bsize - ( (char *)addr - (char *)header ))
+
+
+static inline bool headers( const char * name __attribute__(( unused )), void * addr, HeapManager.Storage.Header *& header, HeapManager.FreeHeader *& freeElem, size_t & size, size_t & alignment ) with ( heapManager ) {
+        header = headerAddr( addr );
+
+        if ( unlikely( heapEnd < addr ) ) {                                     // mmapped ?
+                fakeHeader( header, alignment );
+                size = header->kind.real.blockSize & -3;                // mmap size
+                return true;
+        } // if
+
+        #ifdef __CFA_DEBUG__
+        checkHeader( addr < heapBegin || header < (HeapManager.Storage.Header *)heapBegin, name, addr ); // bad low address ?
+        #endif // __CFA_DEBUG__
+
+        // header may be safe to dereference
+        fakeHeader( header, alignment );
+        #ifdef __CFA_DEBUG__
+        checkHeader( header < (HeapManager.Storage.Header *)heapBegin || (HeapManager.Storage.Header *)heapEnd < header, name, addr ); // bad address ? (offset could be + or -)
+        #endif // __CFA_DEBUG__
+
+        freeElem = (HeapManager.FreeHeader *)((size_t)header->kind.real.home & -3);
+        #ifdef __CFA_DEBUG__
+        if ( freeElem < &freeLists[0] || &freeLists[NoBucketSizes] <= freeElem ) {
+                abort( "Attempt to %s storage %p with corrupted header.\n"
+                           "Possible cause is duplicate free on same block or overwriting of header information.",
+                           name, addr );
+        } // if
+        #endif // __CFA_DEBUG__
+        size = freeElem->blockSize;
+        return false;
+} // headers
+
+
+static inline void * extend( size_t size ) with ( heapManager ) {
+        lock( extlock __cfaabi_dbg_ctx2 );
+        ptrdiff_t rem = heapRemaining - size;
+        if ( rem < 0 ) {
+                // If the size requested is bigger than the current remaining storage, increase the size of the heap.
+
+                size_t increase = libCeiling( size > heapExpand ? size : heapExpand, libAlign() );
+                if ( sbrk( increase ) == (void *)-1 ) {
+                        unlock( extlock );
+                        errno = ENOMEM;
+                        return 0p;
+                } // if
+                #ifdef __STATISTICS__
+                sbrk_calls += 1;
+                sbrk_storage += increase;
+                #endif // __STATISTICS__
+                #ifdef __CFA_DEBUG__
+                // Set new memory to garbage so subsequent uninitialized usages might fail.
+                memset( (char *)heapEnd + heapRemaining, '\377', increase );
+                #endif // __CFA_DEBUG__
+                rem = heapRemaining + increase - size;
+        } // if
+
+        HeapManager.Storage * block = (HeapManager.Storage *)heapEnd;
+        heapRemaining = rem;
+        heapEnd = (char *)heapEnd + size;
+        unlock( extlock );
+        return block;
+} // extend
+
+
 static inline void * doMalloc( size_t size ) with ( heapManager ) {
         HeapManager.Storage * block;                                            // pointer to new block of storage
@@ -541 +488 @@
         // along with the block and is a multiple of the alignment size.
 
-  if ( unlikely( size > ~0ul - sizeof(HeapManager.Storage) ) ) return 0;
+  if ( unlikely( size > ~0ul - sizeof(HeapManager.Storage) ) ) return 0p;
         size_t tsize = size + sizeof(HeapManager.Storage);
         if ( likely( tsize < mmapStart ) ) {                            // small size => sbrk
@@ -574 +521 @@
                 block = freeElem->freeList.pop();
                 #endif // SPINLOCK
-                if ( unlikely( block == 0 ) ) {                                 // no free block ?
+                if ( unlikely( block == 0p ) ) {                                // no free block ?
                         #if defined( SPINLOCK )
                         unlock( freeElem->lock );
@@ -583 +530 @@
 
                         block = (HeapManager.Storage *)extend( tsize ); // mutual exclusion on call
-  if ( unlikely( block == 0 ) ) return 0;
-                        #if defined( SPINLOCK )
+  if ( unlikely( block == 0p ) ) return 0p;
+                #if defined( SPINLOCK )
                 } else {
                         freeElem->freeList = block->header.kind.real.next;
                         unlock( freeElem->lock );
-                        #endif // SPINLOCK
+                #endif // SPINLOCK
                 } // if
 
                 block->header.kind.real.home = freeElem;                // pointer back to free list of apropriate size
         } else {                                                                                        // large size => mmap
-  if ( unlikely( size > ~0ul - pageSize ) ) return 0;
+  if ( unlikely( size > ~0ul - pageSize ) ) return 0p;
                 tsize = libCeiling( tsize, pageSize );                  // must be multiple of page size
                 #ifdef __STATISTICS__
@@ -611 +558 @@
         } // if
 
-        void * area = &(block->data);                                           // adjust off header to user bytes
+        void * addr = &(block->data);                                           // adjust off header to user bytes
 
         #ifdef __CFA_DEBUG__
-        assert( ((uintptr_t)area & (libAlign() - 1)) == 0 ); // minimum alignment ?
+        assert( ((uintptr_t)addr & (libAlign() - 1)) == 0 ); // minimum alignment ?
         __atomic_add_fetch( &allocFree, tsize, __ATOMIC_SEQ_CST );
         if ( traceHeap() ) {
                 enum { BufferSize = 64 };
                 char helpText[BufferSize];
-                int len = snprintf( helpText, BufferSize, "%p = Malloc( %zu ) (allocated %zu)\n", area, size, tsize );
-                // int len = snprintf( helpText, BufferSize, "Malloc %p %zu\n", area, size );
-                __cfaabi_dbg_bits_write( helpText, len );
+                int len = snprintf( helpText, BufferSize, "%p = Malloc( %zu ) (allocated %zu)\n", addr, size, tsize );
+                // int len = snprintf( helpText, BufferSize, "Malloc %p %zu\n", addr, size );
+                __cfaabi_bits_write( STDERR_FILENO, helpText, len ); // print debug/nodebug
         } // if
         #endif // __CFA_DEBUG__
 
-        return area;
+        return addr;
 } // doMalloc
 
@@ -631 +578 @@
 static inline void doFree( void * addr ) with ( heapManager ) {
         #ifdef __CFA_DEBUG__
-        if ( unlikely( heapManager.heapBegin == 0 ) ) {
+        if ( unlikely( heapManager.heapBegin == 0p ) ) {
                 abort( "doFree( %p ) : internal error, called before heap is initialized.", addr );
         } // if
@@ -677 +624 @@
                 char helpText[BufferSize];
                 int len = snprintf( helpText, sizeof(helpText), "Free( %p ) size:%zu\n", addr, size );
-                __cfaabi_dbg_bits_write( helpText, len );
+                __cfaabi_bits_write( STDERR_FILENO, helpText, len ); // print debug/nodebug
         } // if
         #endif // __CFA_DEBUG__
@@ -683 +630 @@
 
 
-size_t checkFree( HeapManager & manager ) with ( manager ) {
+size_t prtFree( HeapManager & manager ) with ( manager ) {
         size_t total = 0;
         #ifdef __STATISTICS__
-        __cfaabi_dbg_bits_acquire();
-        __cfaabi_dbg_bits_print_nolock( "\nBin lists (bin size : free blocks on list)\n" );
+        __cfaabi_bits_acquire();
+        __cfaabi_bits_print_nolock( STDERR_FILENO, "\nBin lists (bin size : free blocks on list)\n" );
         #endif // __STATISTICS__
         for ( unsigned int i = 0; i < maxBucketsUsed; i += 1 ) {
@@ -696 +643 @@
 
                 #if defined( SPINLOCK )
-                for ( HeapManager.Storage * p = freeLists[i].freeList; p != 0; p = p->header.kind.real.next ) {
+                for ( HeapManager.Storage * p = freeLists[i].freeList; p != 0p; p = p->header.kind.real.next ) {
                 #else
-                for ( HeapManager.Storage * p = freeLists[i].freeList.top(); p != 0; p = p->header.kind.real.next.top ) {
+                for ( HeapManager.Storage * p = freeLists[i].freeList.top(); p != 0p; p = p->header.kind.real.next.top ) {
                 #endif // SPINLOCK
                         total += size;
@@ -707 +654 @@
 
                 #ifdef __STATISTICS__
-                __cfaabi_dbg_bits_print_nolock( "%7zu, %-7u  ", size, N );
-                if ( (i + 1) % 8 == 0 ) __cfaabi_dbg_bits_print_nolock( "\n" );
+                __cfaabi_bits_print_nolock( STDERR_FILENO, "%7zu, %-7u  ", size, N );
+                if ( (i + 1) % 8 == 0 ) __cfaabi_bits_print_nolock( STDERR_FILENO, "\n" );
                 #endif // __STATISTICS__
         } // for
         #ifdef __STATISTICS__
-        __cfaabi_dbg_bits_print_nolock( "\ntotal free blocks:%zu\n", total );
-        __cfaabi_dbg_bits_release();
+        __cfaabi_bits_print_nolock( STDERR_FILENO, "\ntotal free blocks:%zu\n", total );
+        __cfaabi_bits_release();
         #endif // __STATISTICS__
         return (char *)heapEnd - (char *)heapBegin - total;
-} // checkFree
+} // prtFree
+
+
+static void ?{}( HeapManager & manager ) with ( manager ) {
+        pageSize = sysconf( _SC_PAGESIZE );
+
+        for ( unsigned int i = 0; i < NoBucketSizes; i += 1 ) { // initialize the free lists
+                freeLists[i].blockSize = bucketSizes[i];
+        } // for
+
+        #ifdef FASTLOOKUP
+        unsigned int idx = 0;
+        for ( unsigned int i = 0; i < LookupSizes; i += 1 ) {
+                if ( i > bucketSizes[idx] ) idx += 1;
+                lookup[i] = idx;
+        } // for
+        #endif // FASTLOOKUP
+
+        if ( setMmapStart( default_mmap_start() ) ) {
+                abort( "HeapManager : internal error, mmap start initialization failure." );
+        } // if
+        heapExpand = default_heap_expansion();
+
+        char * end = (char *)sbrk( 0 );
+        sbrk( (char *)libCeiling( (long unsigned int)end, libAlign() ) - end ); // move start of heap to multiple of alignment
+        heapBegin = heapEnd = sbrk( 0 );                                        // get new start point
+} // HeapManager
+
+
+static void ^?{}( HeapManager & ) {
+        #ifdef __STATISTICS__
+        if ( traceHeapTerm() ) {
+                printStats();
+                // if ( prtfree() ) prtFree( heapManager, true );
+        } // if
+        #endif // __STATISTICS__
+} // ~HeapManager
+
+
+static void memory_startup( void ) __attribute__(( constructor( STARTUP_PRIORITY_MEMORY ) ));
+void memory_startup( void ) {
+        #ifdef __CFA_DEBUG__
+        if ( unlikely( heapBoot ) ) {                                           // check for recursion during system boot
+                // DO NOT USE STREAMS AS THEY MAY BE UNAVAILABLE AT THIS POINT.
+                abort( "boot() : internal error, recursively invoked during system boot." );
+        } // if
+        heapBoot = true;
+        #endif // __CFA_DEBUG__
+
+        //assert( heapManager.heapBegin != 0 );
+        //heapManager{};
+        if ( heapManager.heapBegin == 0p ) heapManager{};
+} // memory_startup
+
+static void memory_shutdown( void ) __attribute__(( destructor( STARTUP_PRIORITY_MEMORY ) ));
+void memory_shutdown( void ) {
+        ^heapManager{};
+} // memory_shutdown
 
 
 static inline void * mallocNoStats( size_t size ) {             // necessary for malloc statistics
         //assert( heapManager.heapBegin != 0 );
-        if ( unlikely( heapManager.heapBegin == 0 ) ) heapManager{}; // called before memory_startup ?
-        void * area = doMalloc( size );
-        if ( unlikely( area == 0 ) ) errno = ENOMEM;            // POSIX
-        return area;
+        if ( unlikely( heapManager.heapBegin == 0p ) ) heapManager{}; // called before memory_startup ?
+        void * addr = doMalloc( size );
+        if ( unlikely( addr == 0p ) ) errno = ENOMEM;           // POSIX
+        return addr;
 } // mallocNoStats
+
+
+static inline void * callocNoStats( size_t noOfElems, size_t elemSize ) {
+        size_t size = noOfElems * elemSize;
+        char * addr = (char *)mallocNoStats( size );
+  if ( unlikely( addr == 0p ) ) return 0p;
+
+        HeapManager.Storage.Header * header;
+        HeapManager.FreeHeader * freeElem;
+        size_t bsize, alignment;
+        bool mapped __attribute__(( unused )) = headers( "calloc", addr, header, freeElem, bsize, alignment );
+        #ifndef __CFA_DEBUG__
+        // Mapped storage is zero filled, but in debug mode mapped memory is scrubbed in doMalloc, so it has to be reset to zero.
+        if ( ! mapped )
+        #endif // __CFA_DEBUG__
+                // Zero entire data space even when > than size => realloc without a new allocation and zero fill works.
+                // <-------00000000000000000000000000000000000000000000000000000> bsize (bucket size)
+                // `-header`-addr                      `-size
+                memset( addr, '\0', bsize - sizeof(HeapManager.Storage) ); // set to zeros
+
+        header->kind.real.blockSize |= 2;                                       // mark as zero filled
+        return addr;
+} // callocNoStats
 
 
@@ -745 +772 @@
         // subtract libAlign() because it is already the minimum alignment
         // add sizeof(Storage) for fake header
-        // #comment TD : this is the only place that calls doMalloc without calling mallocNoStats, why ?
-        char * area = (char *)doMalloc( size + alignment - libAlign() + sizeof(HeapManager.Storage) );
-  if ( unlikely( area == 0 ) ) return area;
+        char * addr = (char *)mallocNoStats( size + alignment - libAlign() + sizeof(HeapManager.Storage) );
+  if ( unlikely( addr == 0p ) ) return addr;
 
         // address in the block of the "next" alignment address
-        char * user = (char *)libCeiling( (uintptr_t)(area + sizeof(HeapManager.Storage)), alignment );
+        char * user = (char *)libCeiling( (uintptr_t)(addr + sizeof(HeapManager.Storage)), alignment );
 
         // address of header from malloc
-        HeapManager.Storage.Header * realHeader = headerAddr( area );
+        HeapManager.Storage.Header * realHeader = headerAddr( addr );
         // address of fake header * before* the alignment location
         HeapManager.Storage.Header * fakeHeader = headerAddr( user );
@@ -763 +789 @@
         return user;
 } // memalignNoStats
+
+
+static inline void * cmemalignNoStats( size_t alignment, size_t noOfElems, size_t elemSize ) {
+        size_t size = noOfElems * elemSize;
+        char * addr = (char *)memalignNoStats( alignment, size );
+  if ( unlikely( addr == 0p ) ) return 0p;
+        HeapManager.Storage.Header * header;
+        HeapManager.FreeHeader * freeElem;
+        size_t bsize;
+        bool mapped __attribute__(( unused )) = headers( "cmemalign", addr, header, freeElem, bsize, alignment );
+        #ifndef __CFA_DEBUG__
+        // Mapped storage is zero filled, but in debug mode mapped memory is scrubbed in doMalloc, so it has to be reset to zero.
+        if ( ! mapped )
+        #endif // __CFA_DEBUG__
+                memset( addr, '\0', dataStorage( bsize, addr, header ) ); // set to zeros
+        header->kind.real.blockSize |= 2;                               // mark as zero filled
+
+        return addr;
+} // cmemalignNoStats
 
 
@@ -776 +821 @@
 extern "C" {
         // The malloc() function allocates size bytes and returns a pointer to the allocated memory. The memory is not
-        // initialized. If size is 0, then malloc() returns either NULL, or a unique pointer value that can later be
+        // initialized. If size is 0, then malloc() returns either 0p, or a unique pointer value that can later be
         // successfully passed to free().
         void * malloc( size_t size ) {
@@ -788 +833 @@
 
         // The calloc() function allocates memory for an array of nmemb elements of size bytes each and returns a pointer to
-        // the allocated memory. The memory is set to zero. If nmemb or size is 0, then calloc() returns either NULL, or a
+        // the allocated memory. The memory is set to zero. If nmemb or size is 0, then calloc() returns either 0p, or a
         // unique pointer value that can later be successfully passed to free().
         void * calloc( size_t noOfElems, size_t elemSize ) {
-                size_t size = noOfElems * elemSize;
                 #ifdef __STATISTICS__
                 __atomic_add_fetch( &calloc_calls, 1, __ATOMIC_SEQ_CST );
-                __atomic_add_fetch( &calloc_storage, size, __ATOMIC_SEQ_CST );
-                #endif // __STATISTICS__
-
-                char * area = (char *)mallocNoStats( size );
-          if ( unlikely( area == 0 ) ) return 0;
+                __atomic_add_fetch( &calloc_storage, noOfElems * elemSize, __ATOMIC_SEQ_CST );
+                #endif // __STATISTICS__
+
+                return callocNoStats( noOfElems, elemSize );
+        } // calloc
+
+        // The realloc() function changes the size of the memory block pointed to by ptr to size bytes. The contents will be
+        // unchanged in the range from the start of the region up to the minimum of the old and new sizes. If the new size
+        // is larger than the old size, the added memory will not be initialized.  If ptr is 0p, then the call is
+        // equivalent to malloc(size), for all values of size; if size is equal to zero, and ptr is not 0p, then the call
+        // is equivalent to free(ptr). Unless ptr is 0p, it must have been returned by an earlier call to malloc(),
+        // calloc() or realloc(). If the area pointed to was moved, a free(ptr) is done.
+        void * realloc( void * oaddr, size_t size ) {
+                #ifdef __STATISTICS__
+                __atomic_add_fetch( &realloc_calls, 1, __ATOMIC_SEQ_CST );
+                #endif // __STATISTICS__
+
+                // If size is equal to 0, either NULL or a pointer suitable to be passed to free() is returned.
+          if ( unlikely( size == 0 ) ) { free( oaddr ); return mallocNoStats( size ); } // special cases
+          if ( unlikely( oaddr == 0p ) ) return mallocNoStats( size );
 
                 HeapManager.Storage.Header * header;
                 HeapManager.FreeHeader * freeElem;
-                size_t asize, alignment;
-                bool mapped __attribute__(( unused )) = headers( "calloc", area, header, freeElem, asize, alignment );
-                #ifndef __CFA_DEBUG__
-                // Mapped storage is zero filled, but in debug mode mapped memory is scrubbed in doMalloc, so it has to be reset to zero.
-                if ( ! mapped )
-                #endif // __CFA_DEBUG__
-                        memset( area, '\0', asize - sizeof(HeapManager.Storage) ); // set to zeros
-
-                header->kind.real.blockSize |= 2;                               // mark as zero filled
-                return area;
-        } // calloc
-
-        // #comment TD : Document this function
-        void * cmemalign( size_t alignment, size_t noOfElems, size_t elemSize ) {
-                size_t size = noOfElems * elemSize;
-                #ifdef __STATISTICS__
-                __atomic_add_fetch( &cmemalign_calls, 1, __ATOMIC_SEQ_CST );
-                __atomic_add_fetch( &cmemalign_storage, size, __ATOMIC_SEQ_CST );
-                #endif // __STATISTICS__
-
-                char * area = (char *)memalignNoStats( alignment, size );
-          if ( unlikely( area == 0 ) ) return 0;
-                HeapManager.Storage.Header * header;
-                HeapManager.FreeHeader * freeElem;
-                size_t asize;
-                bool mapped __attribute__(( unused )) = headers( "cmemalign", area, header, freeElem, asize, alignment );
-                #ifndef __CFA_DEBUG__
-                // Mapped storage is zero filled, but in debug mode mapped memory is scrubbed in doMalloc, so it has to be reset to zero.
-                if ( ! mapped )
-                        #endif // __CFA_DEBUG__
-                        memset( area, '\0', asize - ( (char *)area - (char *)header ) ); // set to zeros
-                header->kind.real.blockSize |= 2;                               // mark as zero filled
-
-                return area;
-        } // cmemalign
-
-        // The realloc() function changes the size of the memory block pointed to by ptr to size bytes. The contents will be
-        // unchanged in the range from the start of the region up to the minimum of the old and new sizes. If the new size
-        // is larger than the old size, the added memory will not be initialized.  If ptr is NULL, then the call is
-        // equivalent to malloc(size), for all values of size; if size is equal to zero, and ptr is not NULL, then the call
-        // is equivalent to free(ptr). Unless ptr is NULL, it must have been returned by an earlier call to malloc(),
-        // calloc() or realloc(). If the area pointed to was moved, a free(ptr) is done.
-        void * realloc( void * addr, size_t size ) {
-                #ifdef __STATISTICS__
-                __atomic_add_fetch( &realloc_calls, 1, __ATOMIC_SEQ_CST );
-                #endif // __STATISTICS__
-
-          if ( unlikely( addr == 0 ) ) return mallocNoStats( size ); // special cases
-          if ( unlikely( size == 0 ) ) { free( addr ); return 0; }
-
-                HeapManager.Storage.Header * header;
-                HeapManager.FreeHeader * freeElem;
-                size_t asize, alignment = 0;
-                headers( "realloc", addr, header, freeElem, asize, alignment );
-
-                size_t usize = asize - ( (char *)addr - (char *)header ); // compute the amount of user storage in the block
-                if ( usize >= size ) {                                                  // already sufficient storage
+                size_t bsize, oalign = 0;
+                headers( "realloc", oaddr, header, freeElem, bsize, oalign );
+
+                size_t odsize = dataStorage( bsize, oaddr, header ); // data storage available in bucket
+          if ( size <= odsize && odsize <= size * 2 ) { // allow up to 50% wasted storage in smaller size
+                        // Do not know size of original allocation => cannot do 0 fill for any additional space because do not know
+                        // where to start filling, i.e., do not overwrite existing values in space.
+                        //
                         // This case does not result in a new profiler entry because the previous one still exists and it must match with
                         // the free for this memory.  Hence, this realloc does not appear in the profiler output.
-                        return addr;
+                        return oaddr;
                 } // if
 
@@ -868 +878 @@
                 #endif // __STATISTICS__
 
-                void * area;
-                if ( unlikely( alignment != 0 ) ) {                             // previous request memalign?
-                        area = memalign( alignment, size );                     // create new aligned area
+                // change size and copy old content to new storage
+
+                void * naddr;
+                if ( unlikely( oalign != 0 ) ) {                                // previous request memalign?
+                        if ( unlikely( header->kind.real.blockSize & 2 ) ) { // previous request zero fill
+                                naddr = cmemalignNoStats( oalign, 1, size ); // create new aligned area
+                        } else {
+                                naddr = memalignNoStats( oalign, size ); // create new aligned area
+                        } // if
                 } else {
-                        area = mallocNoStats( size );                           // create new area
+                        if ( unlikely( header->kind.real.blockSize & 2 ) ) { // previous request zero fill
+                                naddr = callocNoStats( 1, size );               // create new area
+                        } else {
+                                naddr = mallocNoStats( size );                  // create new area
+                        } // if
                 } // if
-          if ( unlikely( area == 0 ) ) return 0;
-                if ( unlikely( header->kind.real.blockSize & 2 ) ) { // previous request zero fill (calloc/cmemalign) ?
-                        assert( (header->kind.real.blockSize & 1) == 0 );
-                        bool mapped __attribute__(( unused )) = headers( "realloc", area, header, freeElem, asize, alignment );
-                        #ifndef __CFA_DEBUG__
-                        // Mapped storage is zero filled, but in debug mode mapped memory is scrubbed in doMalloc, so it has to be reset to zero.
-                        if ( ! mapped )
-                        #endif // __CFA_DEBUG__
-                                memset( (char *)area + usize, '\0', asize - ( (char *)area - (char *)header ) - usize ); // zero-fill back part
-                        header->kind.real.blockSize |= 2;                       // mark new request as zero fill
-                } // if
-                memcpy( area, addr, usize );                                    // copy bytes
-                free( addr );
-                return area;
+          if ( unlikely( naddr == 0p ) ) return 0p;
+
+                headers( "realloc", naddr, header, freeElem, bsize, oalign );
+                size_t ndsize = dataStorage( bsize, naddr, header ); // data storage avilable in bucket
+                // To preserve prior fill, the entire bucket must be copied versus the size.
+                memcpy( naddr, oaddr, MIN( odsize, ndsize ) );  // copy bytes
+                free( oaddr );
+                return naddr;
         } // realloc
 
@@ -898 +912 @@
                 #endif // __STATISTICS__
 
-                void * area = memalignNoStats( alignment, size );
-
-                return area;
+                return memalignNoStats( alignment, size );
         } // memalign
+
+
+        // The cmemalign() function is the same as calloc() with memory alignment.
+        void * cmemalign( size_t alignment, size_t noOfElems, size_t elemSize ) {
+                #ifdef __STATISTICS__
+                __atomic_add_fetch( &cmemalign_calls, 1, __ATOMIC_SEQ_CST );
+                __atomic_add_fetch( &cmemalign_storage, noOfElems * elemSize, __ATOMIC_SEQ_CST );
+                #endif // __STATISTICS__
+
+                return cmemalignNoStats( alignment, noOfElems, elemSize );
+        } // cmemalign
 
         // The function aligned_alloc() is the same as memalign(), except for the added restriction that size should be a
@@ -912 +935 @@
         // The function posix_memalign() allocates size bytes and places the address of the allocated memory in *memptr. The
         // address of the allocated memory will be a multiple of alignment, which must be a power of two and a multiple of
-        // sizeof(void *). If size is 0, then posix_memalign() returns either NULL, or a unique pointer value that can later
+        // sizeof(void *). If size is 0, then posix_memalign() returns either 0p, or a unique pointer value that can later
         // be successfully passed to free(3).
         int posix_memalign( void ** memptr, size_t alignment, size_t size ) {
           if ( alignment < sizeof(void *) || ! libPow2( alignment ) ) return EINVAL; // check alignment
                 * memptr = memalign( alignment, size );
-          if ( unlikely( * memptr == 0 ) ) return ENOMEM;
+          if ( unlikely( * memptr == 0p ) ) return ENOMEM;
                 return 0;
         } // posix_memalign
@@ -930 +953 @@
         // The free() function frees the memory space pointed to by ptr, which must have been returned by a previous call to
         // malloc(), calloc() or realloc().  Otherwise, or if free(ptr) has already been called before, undefined behavior
-        // occurs. If ptr is NULL, no operation is performed.
+        // occurs. If ptr is 0p, no operation is performed.
         void free( void * addr ) {
                 #ifdef __STATISTICS__
@@ -936 +959 @@
                 #endif // __STATISTICS__
 
-                // #comment TD : To decrease nesting I would but the special case in the
-                //               else instead, plus it reads more naturally to have the
-                //               short / normal case instead
-                if ( unlikely( addr == 0 ) ) {                                  // special case
-                        #ifdef __CFA_DEBUG__
-                        if ( traceHeap() ) {
-                                #define nullmsg "Free( 0x0 ) size:0\n"
-                                // Do not debug print free( 0 ), as it can cause recursive entry from sprintf.
-                                __cfaabi_dbg_bits_write( nullmsg, sizeof(nullmsg) - 1 );
-                        } // if
-                        #endif // __CFA_DEBUG__
+          if ( unlikely( addr == 0p ) ) {                                       // special case
+                        // #ifdef __CFA_DEBUG__
+                        // if ( traceHeap() ) {
+                        //      #define nullmsg "Free( 0x0 ) size:0\n"
+                        //      // Do not debug print free( 0p ), as it can cause recursive entry from sprintf.
+                        //      __cfaabi_dbg_write( nullmsg, sizeof(nullmsg) - 1 );
+                        // } // if
+                        // #endif // __CFA_DEBUG__
                         return;
                 } // exit
@@ -953 +973 @@
         } // free
 
-        // The mallopt() function adjusts parameters that control the behavior of the memory-allocation functions (see
-        // malloc(3)). The param argument specifies the parameter to be modified, and value specifies the new value for that
-        // parameter.
-        int mallopt( int option, int value ) {
-                choose( option ) {
-                  case M_TOP_PAD:
-                        if ( setHeapExpand( value ) ) fallthru default;
-                  case M_MMAP_THRESHOLD:
-                        if ( setMmapStart( value ) ) fallthru default;
-                  default:
-                        // #comment TD : 1 for unsopported feels wrong
-                        return 1;                                                                       // success, or unsupported
-                } // switch
-                return 0;                                                                               // error
-        } // mallopt
-
-        // The malloc_trim() function attempts to release free memory at the top of the heap (by calling sbrk(2) with a
-        // suitable argument).
-        int malloc_trim( size_t ) {
-                return 0;                                                                               // => impossible to release memory
-        } // malloc_trim
-
-        // The malloc_usable_size() function returns the number of usable bytes in the block pointed to by ptr, a pointer to
-        // a block of memory allocated by malloc(3) or a related function.
-        size_t malloc_usable_size( void * addr ) {
-          if ( unlikely( addr == 0 ) ) return 0;                        // null allocation has 0 size
-
-                HeapManager.Storage.Header * header;
-                HeapManager.FreeHeader * freeElem;
-                size_t size, alignment;
-
-                headers( "malloc_usable_size", addr, header, freeElem, size, alignment );
-                size_t usize = size - ( (char *)addr - (char *)header ); // compute the amount of user storage in the block
-                return usize;
-        } // malloc_usable_size
-
-
-    // The malloc_alignment() function returns the alignment of the allocation.
+
+        // The malloc_alignment() function returns the alignment of the allocation.
         size_t malloc_alignment( void * addr ) {
-          if ( unlikely( addr == 0 ) ) return libAlign();       // minimum alignment
+          if ( unlikely( addr == 0p ) ) return libAlign();      // minimum alignment
                 HeapManager.Storage.Header * header = headerAddr( addr );
                 if ( (header->kind.fake.alignment & 1) == 1 ) { // fake header ?
@@ -1002 +986 @@
 
 
-    // The malloc_zero_fill() function returns true if the allocation is zero filled, i.e., initially allocated by calloc().
+        // The malloc_zero_fill() function returns true if the allocation is zero filled, i.e., initially allocated by calloc().
         bool malloc_zero_fill( void * addr ) {
-          if ( unlikely( addr == 0 ) ) return false;            // null allocation is not zero fill
+          if ( unlikely( addr == 0p ) ) return false;           // null allocation is not zero fill
                 HeapManager.Storage.Header * header = headerAddr( addr );
                 if ( (header->kind.fake.alignment & 1) == 1 ) { // fake header ?
@@ -1013 +997 @@
 
 
-    // The malloc_stats() function prints (on default standard error) statistics about memory allocated by malloc(3) and
-    // related functions.
+        // The malloc_usable_size() function returns the number of usable bytes in the block pointed to by ptr, a pointer to
+        // a block of memory allocated by malloc(3) or a related function.
+        size_t malloc_usable_size( void * addr ) {
+          if ( unlikely( addr == 0p ) ) return 0;                       // null allocation has 0 size
+                HeapManager.Storage.Header * header;
+                HeapManager.FreeHeader * freeElem;
+                size_t bsize, alignment;
+
+                headers( "malloc_usable_size", addr, header, freeElem, bsize, alignment );
+                return dataStorage( bsize, addr, header );      // data storage in bucket
+        } // malloc_usable_size
+
+
+        // The malloc_stats() function prints (on default standard error) statistics about memory allocated by malloc(3) and
+        // related functions.
         void malloc_stats( void ) {
                 #ifdef __STATISTICS__
                 printStats();
-                if ( checkFree() ) checkFree( heapManager );
+                if ( prtFree() ) prtFree( heapManager );
                 #endif // __STATISTICS__
         } // malloc_stats
 
         // The malloc_stats_fd() function changes the file descripter where malloc_stats() writes the statistics.
-        int malloc_stats_fd( int fd ) {
+        int malloc_stats_fd( int fd __attribute__(( unused )) ) {
                 #ifdef __STATISTICS__
                 int temp = statfd;
@@ -1033 +1030 @@
         } // malloc_stats_fd
 
+
+        // The mallopt() function adjusts parameters that control the behavior of the memory-allocation functions (see
+        // malloc(3)). The param argument specifies the parameter to be modified, and value specifies the new value for that
+        // parameter.
+        int mallopt( int option, int value ) {
+                choose( option ) {
+                  case M_TOP_PAD:
+                        if ( setHeapExpand( value ) ) return 1;
+                  case M_MMAP_THRESHOLD:
+                        if ( setMmapStart( value ) ) return 1;
+                } // switch
+                return 0;                                                                               // error, unsupported
+        } // mallopt
+
+        // The malloc_trim() function attempts to release free memory at the top of the heap (by calling sbrk(2) with a
+        // suitable argument).
+        int malloc_trim( size_t ) {
+                return 0;                                                                               // => impossible to release memory
+        } // malloc_trim
+
+
         // The malloc_info() function exports an XML string that describes the current state of the memory-allocation
         // implementation in the caller.  The string is printed on the file stream stream.  The exported string includes
         // information about all arenas (see malloc(3)).
         int malloc_info( int options, FILE * stream ) {
+                if ( options != 0 ) { errno = EINVAL; return -1; }
                 return printStatsXML( stream );
         } // malloc_info
@@ -1046 +1065 @@
         // structure is returned as the function result.  (It is the caller's responsibility to free(3) this memory.)
         void * malloc_get_state( void ) {
-                return 0;                                                                               // unsupported
+                return 0p;                                                                              // unsupported
         } // malloc_get_state
 
@@ -1058 +1077 @@
 
 
+// Must have CFA linkage to overload with C linkage realloc.
+void * realloc( void * oaddr, size_t nalign, size_t size ) {
+        #ifdef __STATISTICS__
+        __atomic_add_fetch( &realloc_calls, 1, __ATOMIC_SEQ_CST );
+        #endif // __STATISTICS__
+
+        // If size is equal to 0, either NULL or a pointer suitable to be passed to free() is returned.
+  if ( unlikely( size == 0 ) ) { free( oaddr ); return mallocNoStats( size ); } // special cases
+  if ( unlikely( oaddr == 0p ) ) return mallocNoStats( size );
+
+        if ( unlikely( nalign == 0 ) ) nalign = libAlign();     // reset alignment to minimum
+        #ifdef __CFA_DEBUG__
+        else
+                checkAlign( nalign );                                                   // check alignment
+        #endif // __CFA_DEBUG__
+
+        HeapManager.Storage.Header * header;
+        HeapManager.FreeHeader * freeElem;
+        size_t bsize, oalign = 0;
+        headers( "realloc", oaddr, header, freeElem, bsize, oalign );
+        size_t odsize = dataStorage( bsize, oaddr, header ); // data storage available in bucket
+
+  if ( oalign != 0 && (uintptr_t)oaddr % nalign == 0 ) { // has alignment and just happens to work out
+                headerAddr( oaddr )->kind.fake.alignment = nalign | 1; // update alignment (could be the same)
+                return realloc( oaddr, size );
+        } // if
+
+        #ifdef __STATISTICS__
+        __atomic_add_fetch( &realloc_storage, size, __ATOMIC_SEQ_CST );
+        #endif // __STATISTICS__
+
+        // change size and copy old content to new storage
+
+        void * naddr;
+        if ( unlikely( header->kind.real.blockSize & 2 ) ) { // previous request zero fill
+                naddr = cmemalignNoStats( nalign, 1, size );    // create new aligned area
+        } else {
+                naddr = memalignNoStats( nalign, size );                // create new aligned area
+        } // if
+
+        headers( "realloc", naddr, header, freeElem, bsize, oalign );
+        size_t ndsize = dataStorage( bsize, naddr, header ); // data storage avilable in bucket
+        // To preserve prior fill, the entire bucket must be copied versus the size.
+        memcpy( naddr, oaddr, MIN( odsize, ndsize ) );          // copy bytes
+        free( oaddr );
+        return naddr;
+} // realloc
+
+
 // Local Variables: //
 // tab-width: 4 //