3

私はこのコードを持っています：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/time.h>
#include <sys/resource.h>

double get_time()
{
    struct timeval t;
    struct timezone tzp;
    gettimeofday(&t, &tzp);
    return t.tv_sec + t.tv_usec*1e-6;
}

#define LL_APPEND(what, where, type) { \
    what->next = NULL; \
    what->prev = NULL; \
    if(!where) { \
        where = what; \
    } else { \
        type current = where; \
        while(current->next != NULL) \
            current = current->next; \
        current->next = what; \
        what->prev = current; \
    } \
}

struct edge {
    struct node *from;
    struct node *to;
    char *label;
};

struct edge_list {
    struct edge *edge;
    struct edge_list *prev;
    struct edge_list *next;
};

struct graph {
    struct node_list *nodes;
    struct edge_list *edges;
    int nodes_count;
    int edges_count;
};

struct node {
    char *name;
    struct edge_list *in;
    struct edge_list *out;
    struct graph *graph;
};

struct node_list {
    struct node *node;
    struct node_list *prev;
    struct node_list *next;
};

struct graph *graph_create_empty() {
    struct graph *graph = malloc(sizeof(struct graph));

    graph->nodes = NULL;
    graph->edges = NULL;
    graph->nodes_count = 0;
    graph->edges_count = 0;

    return graph;
}


void edge_destroy(struct edge *edge) {
    free(edge->label);
    free(edge);
}


void node_destroy(struct node *node) {
    struct edge_list *tmp_edge, *edge;

    edge = node->in;
    while(edge != NULL) {
        tmp_edge = edge;
        edge     = edge->next;
        free(tmp_edge);
    }

    edge = node->out;
    while(edge != NULL) {
        tmp_edge = edge;
        edge     = edge->next;
        free(tmp_edge);
    }

    free(node->name);
    free(node);
}

void graph_destroy(struct graph *graph) {
    struct edge_list *tmp_edge, *edge;
    edge = graph->edges;
    while(edge != NULL) {
        tmp_edge = edge;
        edge     = edge->next;
        edge_destroy(tmp_edge->edge);
        free(tmp_edge);
    }

    struct node_list *tmp_node, *node;
    node = graph->nodes;
    while(node != NULL) {
        tmp_node = node;
        node     = node->next;
        node_destroy(tmp_node->node);
        free(tmp_node);
    }

    free(graph);
}


void graph_add_edge(struct graph *graph, struct edge *edge) {
    struct edge_list *new_edge = malloc(sizeof(struct edge_list));
    new_edge->edge = edge;

    LL_APPEND(new_edge, graph->edges, struct edge_list *);
    graph->edges_count++;
}

void graph_add_node(struct graph *graph, struct node *node) {
    node->graph = graph;

    struct node_list *new_node = malloc(sizeof(struct node_list));
    new_node->node = node;

    LL_APPEND(new_node, graph->nodes, struct node_list *);
    graph->nodes_count++;
}

struct node *node_create(const char *name, struct graph *graph) {
    struct node *node = malloc(sizeof(struct node));

    node->name = malloc(strlen(name)+1);
    strcpy(node->name, name);

    node->in  = NULL;
    node->out = NULL;

    if(graph)
        graph_add_node(graph, node);

    return node;
}

void node_add_edge(struct node *node, struct edge *edge) {
    struct edge_list *new_edge = malloc(sizeof(struct edge_list));

    if(node == edge->to) {
        LL_APPEND(new_edge, node->out, struct edge_list *);
    } else {
        LL_APPEND(new_edge, node->in, struct edge_list *);
    }
}

void node_connect(const char *label, struct node *from, struct node *to) {
    if(from->graph != to->graph || from->graph == NULL) 
        return;

    struct edge *edge = malloc(sizeof(struct edge));

    edge->label = malloc(strlen(label)+1);
    strcpy(edge->label, label);

    edge->from = from;
    edge->to   = to;

    graph_add_edge(from->graph, edge);
    node_add_edge(from,         edge);
    node_add_edge(to,           edge);
}

int main(int argc, char *argv[]) {
    double start = get_time();

    for(int i = 0; i < 100000; i++) {
        struct graph *graph = graph_create_empty();

        // Create the nodes
        struct node *useful_demand_heat = node_create("useful_demand_heat", graph);
        struct node *useful_demand_elec = node_create("useful_demand_elec", graph);

        struct node *space_heater_coal  = node_create("space_heater_coal", graph);
        struct node *space_heater_gas   = node_create("space_heater_gas", graph);
        struct node *space_heater_oil   = node_create("space_heater_oil", graph);
        struct node *space_heater_chp   = node_create("space_heater_chp", graph);
        struct node *space_heater_elec  = node_create("space_heater_elec", graph);

        struct node *final_demand_coal  = node_create("final_demand_coal", graph);
        struct node *final_demand_gas  = node_create("final_demand_gas", graph);
        struct node *final_demand_oil  = node_create("final_demand_oil", graph);
        struct node *final_demand_elec  = node_create("final_demand_elec", graph);

        struct node *lv_network = node_create("lv_network", graph);
        struct node *mv_network = node_create("mv_network", graph);
        struct node *hv_network = node_create("hv_network", graph);

        struct node *coal_plant = node_create("coal_plant", graph);
        struct node *elec_import = node_create("elec_import", graph);

        // Edges
        node_connect("electricity", elec_import, hv_network);
        node_connect("electricity", coal_plant, hv_network);

        node_connect("electricity", hv_network, mv_network);
        node_connect("electricity", mv_network, lv_network);
        node_connect("electricity", lv_network, final_demand_elec);

        node_connect("electricity", final_demand_elec, space_heater_elec);
        node_connect("coal", final_demand_coal, space_heater_coal);
        node_connect("gas", final_demand_gas, space_heater_gas);
        node_connect("gas", final_demand_gas, space_heater_chp);
        node_connect("oil", final_demand_oil, space_heater_oil);

        node_connect("heat", space_heater_coal, useful_demand_heat);
        node_connect("heat", space_heater_gas, useful_demand_heat);
        node_connect("heat", space_heater_oil, useful_demand_heat);
        node_connect("heat", space_heater_chp, useful_demand_heat);

        node_connect("electricity", space_heater_chp, useful_demand_elec);
        node_connect("electricity", space_heater_elec, useful_demand_elec);
        graph_destroy(graph);
    }

    double finish = get_time();
    printf("Took %.5f ms to run\n", (finish - start));
}

valgrindを実行すると、次の警告が表示されます。

==44508== Memcheck, a memory error detector
==44508== Copyright (C) 2002-2012, and GNU GPL'd, by Julian Seward et al.
==44508== Using Valgrind-3.8.1 and LibVEX; rerun with -h for copyright info
==44508== Command: ./graph
==44508== 
==44508== WARNING: Support on MacOS 10.8 is experimental and mostly broken.
==44508== WARNING: Expect incorrect results, assertions and crashes.
==44508== WARNING: In particular, Memcheck on 32-bit programs will fail to
==44508== WARNING: detect any errors associated with heap-allocated data.
==44508== 
--44508-- ./graph:
--44508-- dSYM directory is missing; consider using --dsymutil=yes
Took 22.74883 ms to run
Done.
==44508== 
==44508== HEAP SUMMARY:
==44508==     in use at exit: 74,666 bytes in 365 blocks
==44508==   total heap usage: 12,900,518 allocs, 12,900,153 frees, 284,078,620 bytes allocated
==44508== 
==44508== 16 bytes in 1 blocks are definitely lost in loss record 7 of 88
==44508==    at 0x54D7: malloc_zone_malloc (in /usr/local/Cellar/valgrind/3.8.1/lib/valgrind/vgpreload_memcheck-amd64-darwin.so)
==44508==    by 0x373381: recursive_mutex_init (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x372025: _objc_init (in /usr/lib/libobjc.A.dylib)
==44508==    by 0xBB27: libSystem_initializer (in /usr/lib/libSystem.B.dylib)
==44508==    by 0x7FFF5FC13377: ImageLoaderMachO::doModInitFunctions(ImageLoader::LinkContext const&) (in /usr/lib/dyld)
==44508==    by 0x7FFF5FC13761: ImageLoaderMachO::doInitialization(ImageLoader::LinkContext const&) (in /usr/lib/dyld)
==44508==    by 0x7FFF5FC1006D: ImageLoader::recursiveInitialization(ImageLoader::LinkContext const&, unsigned int, ImageLoader::InitializerTimingList&) (in /usr/lib/dyld)
==44508==    by 0x7FFF5FC0FFC3: ImageLoader::recursiveInitialization(ImageLoader::LinkContext const&, unsigned int, ImageLoader::InitializerTimingList&) (in /usr/lib/dyld)
==44508==    by 0x7FFF5FC0FEB9: ImageLoader::runInitializers(ImageLoader::LinkContext const&, ImageLoader::InitializerTimingList&) (in /usr/lib/dyld)
==44508==    by 0x7FFF5FC01F9D: dyld::initializeMainExecutable() (in /usr/lib/dyld)
==44508==    by 0x7FFF5FC05B03: dyld::_main(macho_header const*, unsigned long, int, char const**, char const**, char const**, unsigned long*) (in /usr/lib/dyld)
==44508==    by 0x7FFF5FC01396: dyldbootstrap::start(macho_header const*, int, char const**, long, macho_header const*, unsigned long*) (in /usr/lib/dyld)
==44508== 
==44508== 32 bytes in 1 blocks are possibly lost in loss record 24 of 88
==44508==    at 0x5A95: malloc_zone_calloc (in /usr/local/Cellar/valgrind/3.8.1/lib/valgrind/vgpreload_memcheck-amd64-darwin.so)
==44508==    by 0x3756EA: NXHashInsert (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x37546C: NXCreateHashTableFromZone (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x374788: _read_images (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x3739EB: map_images_nolock (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x3734F3: map_images (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x7FFF5FC04936: dyld::notifyBatchPartial(dyld_image_states, bool, char const* (*)(dyld_image_states, unsigned int, dyld_image_info const*)) (in /usr/lib/dyld)
==44508==    by 0x7FFF5FC0467C: dyld::registerImageStateBatchChangeHandler(dyld_image_states, char const* (*)(dyld_image_states, unsigned int, dyld_image_info const*)) (in /usr/lib/dyld)
==44508==    by 0x83ED9: dyld_register_image_state_change_handler (in /usr/lib/system/libdyld.dylib)
==44508==    by 0x37204C: _objc_init (in /usr/lib/libobjc.A.dylib)
==44508==    by 0xBB27: libSystem_initializer (in /usr/lib/libSystem.B.dylib)
==44508==    by 0x7FFF5FC13377: ImageLoaderMachO::doModInitFunctions(ImageLoader::LinkContext const&) (in /usr/lib/dyld)
==44508== 
==44508== 64 bytes in 2 blocks are possibly lost in loss record 36 of 88
==44508==    at 0x5A95: malloc_zone_calloc (in /usr/local/Cellar/valgrind/3.8.1/lib/valgrind/vgpreload_memcheck-amd64-darwin.so)
==44508==    by 0x3756EA: NXHashInsert (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x385324: realizeClass(class_t*) (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x374E9C: _read_images (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x3739EB: map_images_nolock (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x3734F3: map_images (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x7FFF5FC04936: dyld::notifyBatchPartial(dyld_image_states, bool, char const* (*)(dyld_image_states, unsigned int, dyld_image_info const*)) (in /usr/lib/dyld)
==44508==    by 0x7FFF5FC0467C: dyld::registerImageStateBatchChangeHandler(dyld_image_states, char const* (*)(dyld_image_states, unsigned int, dyld_image_info const*)) (in /usr/lib/dyld)
==44508==    by 0x83ED9: dyld_register_image_state_change_handler (in /usr/lib/system/libdyld.dylib)
==44508==    by 0x37204C: _objc_init (in /usr/lib/libobjc.A.dylib)
==44508==    by 0xBB27: libSystem_initializer (in /usr/lib/libSystem.B.dylib)
==44508==    by 0x7FFF5FC13377: ImageLoaderMachO::doModInitFunctions(ImageLoader::LinkContext const&) (in /usr/lib/dyld)
==44508== 
==44508== 64 bytes in 2 blocks are possibly lost in loss record 37 of 88
==44508==    at 0x5A95: malloc_zone_calloc (in /usr/local/Cellar/valgrind/3.8.1/lib/valgrind/vgpreload_memcheck-amd64-darwin.so)
==44508==    by 0x3756EA: NXHashInsert (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x3757F6: _NXHashRehashToCapacity (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x375748: NXHashInsert (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x385324: realizeClass(class_t*) (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x374E9C: _read_images (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x3739EB: map_images_nolock (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x3734F3: map_images (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x7FFF5FC04936: dyld::notifyBatchPartial(dyld_image_states, bool, char const* (*)(dyld_image_states, unsigned int, dyld_image_info const*)) (in /usr/lib/dyld)
==44508==    by 0x7FFF5FC0467C: dyld::registerImageStateBatchChangeHandler(dyld_image_states, char const* (*)(dyld_image_states, unsigned int, dyld_image_info const*)) (in /usr/lib/dyld)
==44508==    by 0x83ED9: dyld_register_image_state_change_handler (in /usr/lib/system/libdyld.dylib)
==44508==    by 0x37204C: _objc_init (in /usr/lib/libobjc.A.dylib)
==44508== 
==44508== 64 bytes in 1 blocks are definitely lost in loss record 38 of 88
==44508==    at 0x54D7: malloc_zone_malloc (in /usr/local/Cellar/valgrind/3.8.1/lib/valgrind/vgpreload_memcheck-amd64-darwin.so)
==44508==    by 0x3733CF: recursive_mutex_init (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x372025: _objc_init (in /usr/lib/libobjc.A.dylib)
==44508==    by 0xBB27: libSystem_initializer (in /usr/lib/libSystem.B.dylib)
==44508==    by 0x7FFF5FC13377: ImageLoaderMachO::doModInitFunctions(ImageLoader::LinkContext const&) (in /usr/lib/dyld)
==44508==    by 0x7FFF5FC13761: ImageLoaderMachO::doInitialization(ImageLoader::LinkContext const&) (in /usr/lib/dyld)
==44508==    by 0x7FFF5FC1006D: ImageLoader::recursiveInitialization(ImageLoader::LinkContext const&, unsigned int, ImageLoader::InitializerTimingList&) (in /usr/lib/dyld)
==44508==    by 0x7FFF5FC0FFC3: ImageLoader::recursiveInitialization(ImageLoader::LinkContext const&, unsigned int, ImageLoader::InitializerTimingList&) (in /usr/lib/dyld)
==44508==    by 0x7FFF5FC0FEB9: ImageLoader::runInitializers(ImageLoader::LinkContext const&, ImageLoader::InitializerTimingList&) (in /usr/lib/dyld)
==44508==    by 0x7FFF5FC01F9D: dyld::initializeMainExecutable() (in /usr/lib/dyld)
==44508==    by 0x7FFF5FC05B03: dyld::_main(macho_header const*, unsigned long, int, char const**, char const**, char const**, unsigned long*) (in /usr/lib/dyld)
==44508==    by 0x7FFF5FC01396: dyldbootstrap::start(macho_header const*, int, char const**, long, macho_header const*, unsigned long*) (in /usr/lib/dyld)
==44508== 
==44508== 72 (24 direct, 48 indirect) bytes in 1 blocks are definitely lost in loss record 39 of 88
==44508==    at 0x5A95: malloc_zone_calloc (in /usr/local/Cellar/valgrind/3.8.1/lib/valgrind/vgpreload_memcheck-amd64-darwin.so)
==44508==    by 0x3796D2: _objc_fetch_pthread_data (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x382C4D: _fetchInitializingClassList(signed char) (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x379181: _class_initialize (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x379137: _class_initialize (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x379137: _class_initialize (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x379137: _class_initialize (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x3790F2: prepareForMethodLookup (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x378EEE: lookUpMethod (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x3772FB: objc_msgSend (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x2DEE87: _libxpc_initializer (in /usr/lib/system/libxpc.dylib)
==44508==    by 0xBB2C: libSystem_initializer (in /usr/lib/libSystem.B.dylib)
==44508== 
==44508== 96 bytes in 3 blocks are possibly lost in loss record 43 of 88
==44508==    at 0x5A95: malloc_zone_calloc (in /usr/local/Cellar/valgrind/3.8.1/lib/valgrind/vgpreload_memcheck-amd64-darwin.so)
==44508==    by 0x3756EA: NXHashInsert (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x38533D: realizeClass(class_t*) (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x3845D0: realizeClass(class_t*) (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x374E9C: _read_images (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x3739EB: map_images_nolock (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x3734F3: map_images (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x7FFF5FC04936: dyld::notifyBatchPartial(dyld_image_states, bool, char const* (*)(dyld_image_states, unsigned int, dyld_image_info const*)) (in /usr/lib/dyld)
==44508==    by 0x7FFF5FC0467C: dyld::registerImageStateBatchChangeHandler(dyld_image_states, char const* (*)(dyld_image_states, unsigned int, dyld_image_info const*)) (in /usr/lib/dyld)
==44508==    by 0x83ED9: dyld_register_image_state_change_handler (in /usr/lib/system/libdyld.dylib)
==44508==    by 0x37204C: _objc_init (in /usr/lib/libobjc.A.dylib)
==44508==    by 0xBB27: libSystem_initializer (in /usr/lib/libSystem.B.dylib)
==44508== 
==44508== 96 bytes in 3 blocks are possibly lost in loss record 44 of 88
==44508==    at 0x5A95: malloc_zone_calloc (in /usr/local/Cellar/valgrind/3.8.1/lib/valgrind/vgpreload_memcheck-amd64-darwin.so)
==44508==    by 0x3756EA: NXHashInsert (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x3757F6: _NXHashRehashToCapacity (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x375748: NXHashInsert (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x38533D: realizeClass(class_t*) (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x3845D0: realizeClass(class_t*) (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x374E9C: _read_images (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x3739EB: map_images_nolock (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x3734F3: map_images (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x7FFF5FC04936: dyld::notifyBatchPartial(dyld_image_states, bool, char const* (*)(dyld_image_states, unsigned int, dyld_image_info const*)) (in /usr/lib/dyld)
==44508==    by 0x7FFF5FC0467C: dyld::registerImageStateBatchChangeHandler(dyld_image_states, char const* (*)(dyld_image_states, unsigned int, dyld_image_info const*)) (in /usr/lib/dyld)
==44508==    by 0x83ED9: dyld_register_image_state_change_handler (in /usr/lib/system/libdyld.dylib)
==44508== 
==44508== 120 bytes in 5 blocks are possibly lost in loss record 47 of 88
==44508==    at 0x5A95: malloc_zone_calloc (in /usr/local/Cellar/valgrind/3.8.1/lib/valgrind/vgpreload_memcheck-amd64-darwin.so)
==44508==    by 0x37566D: NXHashInsert (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x3757F6: _NXHashRehashToCapacity (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x375748: NXHashInsert (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x38533D: realizeClass(class_t*) (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x3845D0: realizeClass(class_t*) (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x374E9C: _read_images (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x3739EB: map_images_nolock (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x3734F3: map_images (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x7FFF5FC04936: dyld::notifyBatchPartial(dyld_image_states, bool, char const* (*)(dyld_image_states, unsigned int, dyld_image_info const*)) (in /usr/lib/dyld)
==44508==    by 0x7FFF5FC0467C: dyld::registerImageStateBatchChangeHandler(dyld_image_states, char const* (*)(dyld_image_states, unsigned int, dyld_image_info const*)) (in /usr/lib/dyld)
==44508==    by 0x83ED9: dyld_register_image_state_change_handler (in /usr/lib/system/libdyld.dylib)
==44508== 
...
==44508== 8,192 bytes in 8 blocks are definitely lost in loss record 86 of 88
==44508==    at 0x54D7: malloc_zone_malloc (in /usr/local/Cellar/valgrind/3.8.1/lib/valgrind/vgpreload_memcheck-amd64-darwin.so)
==44508==    by 0x3745AE: objc::DenseMap<objc_object*, unsigned long, true, objc::DenseMapInfo<objc_object*>, objc::DenseMapInfo<unsigned long> >::init(unsigned int) (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x37455A: arr_init (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x3739DF: map_images_nolock (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x3734F3: map_images (in /usr/lib/libobjc.A.dylib)
==44508==    by 0x7FFF5FC04936: dyld::notifyBatchPartial(dyld_image_states, bool, char const* (*)(dyld_image_states, unsigned int, dyld_image_info const*)) (in /usr/lib/dyld)
==44508==    by 0x7FFF5FC0467C: dyld::registerImageStateBatchChangeHandler(dyld_image_states, char const* (*)(dyld_image_states, unsigned int, dyld_image_info const*)) (in /usr/lib/dyld)
==44508==    by 0x83ED9: dyld_register_image_state_change_handler (in /usr/lib/system/libdyld.dylib)
==44508==    by 0x37204C: _objc_init (in /usr/lib/libobjc.A.dylib)
==44508==    by 0xBB27: libSystem_initializer (in /usr/lib/libSystem.B.dylib)
==44508==    by 0x7FFF5FC13377: ImageLoaderMachO::doModInitFunctions(ImageLoader::LinkContext const&) (in /usr/lib/dyld)
==44508==    by 0x7FFF5FC13761: ImageLoaderMachO::doInitialization(ImageLoader::LinkContext const&) (in /usr/lib/dyld)
==44508== 
==44508== 10,808 bytes in 1 blocks are possibly lost in loss record 87 of 88
==44508==    at 0x5237: malloc (in /usr/local/Cellar/valgrind/3.8.1/lib/valgrind/vgpreload_memcheck-amd64-darwin.so)
==44508==    by 0x101745: tzsetwall_basic (in /usr/lib/system/libsystem_c.dylib)
==44508==    by 0x103043: localtime (in /usr/lib/system/libsystem_c.dylib)
==44508==    by 0xFB52C: gettimeofday (in /usr/lib/system/libsystem_c.dylib)
==44508==    by 0x1000017A0: main (in ./graph)
==44508== 
==44508== LEAK SUMMARY:
==44508==    definitely lost: 9,729 bytes in 16 blocks
==44508==    indirectly lost: 1,236 bytes in 7 blocks
==44508==      possibly lost: 15,749 bytes in 68 blocks
==44508==    still reachable: 47,952 bytes in 274 blocks
==44508==         suppressed: 0 bytes in 0 blocks
==44508== Reachable blocks (those to which a pointer was found) are not shown.
==44508== To see them, rerun with: --leak-check=full --show-reachable=yes
==44508== 
==44508== For counts of detected and suppressed errors, rerun with: -v
==44508== ERROR SUMMARY: 22 errors from 22 contexts (suppressed: 0 from 0)

彼らは私のコードを指していませんが、それでもリークがあります。心配する必要がありますか？

（また、私が何か間違ったことをしているのか、コードスタイルを改善しているのかについてのポインタ（私がそこで何をしたかを参照してください！）は大歓迎です！）

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3 に答える 3

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最新で最高のValgrindの3.8.1を使用しています。OSX 10.8のサポートは、フルバージョン（3.8.0）より前に導入され、valgrindのニュースページに次のように記載されています。

MacOSX 10.8の初期サポートはありますが、現在、本格的な作業には使用できません。

3.8.0バージョンもありReduced noise (false positive) level on MacOSX 10.6/10.7ますが、10.8ではそのような運はありません。valgrindダウンロードページで現在のリリースを確認することを強くお勧めします。最新リリースの通知については、そこからサブスクライブすることもできます（Mac OSX10.8のサポートが向上するはずです）。

注： valgrind3.7.0ではOSX10.7のサポートが追加されたため、サポートが向上するためには、おそらく3.9がリリースされるのを待つだけで済みます。

「メモリリークの可能性」に関する限り、--show-possibly-lost=noフラグを使用してこれらの警告をいつでも抑制できます。今のところ、valgrindが提供するすべてのものを一粒の塩で処理します。

私があなたに指摘したその最後のページは言う：

「失われた可能性がある」とは、割り当てられたブロックの中央を指す可能性のあるポインタを使用して異常な処理を行っている場合を除き、プログラムがメモリリークを起こしていることを意味します。考えられる原因については、ユーザーマニュアルを参照してください。

OSX 10.8をより適切にサポートする新しいバージョンのvalgrindがリリースされるまで、LinuxディストリビューションでOracleのVirtualBoxを使用することを強くお勧めします。そこでコードを実行でき、すべて無料です。OSX10.8のバージョンもあります。Linux仮想ボックスでプログラムを実行すると、エラーは報告されません（少し古いバージョンがあることに注意してください）。そのため、誤検知が発生する可能性が高くなります。

mike@mike-VirtualBox:~/C$ valgrind ./a.out
==12465== Memcheck, a memory error detector
==12465== Copyright (C) 2002-2011, and GNU GPL'd, by Julian Seward et al.
==12465== Using Valgrind-3.7.0 and LibVEX; rerun with -h for copyright info
==12465== Command: ./a.out
==12465== 
Took 43.77033 ms to run
==12465== 
==12465== HEAP SUMMARY:
==12465==     in use at exit: 0 bytes in 0 blocks
==12465==   total heap usage: 12,900,000 allocs, 12,900,000 frees, 284,000,000 bytes allocated
==12465== 
==12465== All heap blocks were freed -- no leaks are possible
==12465== 
==12465== For counts of detected and suppressed errors, rerun with: -v
==12465== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 2 from 2)
mike@mike-VirtualBox:~/C$
于 2013-03-25T12:36:33.820 に答える
1

私は一般的にあなたが最も心配するべきでありdefinitely lost、それは本当に図書館に依存します。Possibly lostメモリが失われたことを示す場合もありますが、実際にはそうではありません。これは、複雑なデータ型があり、ポインタの「ネスト」、キャスト、およびポインタの受け渡しを使用している場合に発生する可能性があります。

もう1つのポイントは、画像を操作していて、問題が画像の割り当てまたは割り当て解除にある場合、多くのバイトが失われる可能性があるため、心配する必要があります。これは、方法によっては非常に急速に蓄積され、メモリを消費する可能性があるためです。頻繁にそれをします。

一方、*_init関数を呼び出す必要があるライブラリがあります。このライブラリは、いくつかのグローバル変数を設定し、それらをクリーンアップすることはありません。それはまったく無害です。

valgrindにこれらをいわゆるサプレッションファイルとブレンドさせることができます。

于 2013-03-25T11:30:17.577 に答える
0

心配する必要がありますか？

valgrindがシステムで正しく機能しないことを心配する必要がありますか？あまり; システムで正しく動作する他のメモリプロファイラーがあります。

プログラムがメモリリークすることを心配する必要がありますか？まあ、正しく動作するメモリプロファイラーでそれをテストするまで、あなたは確かにわかりません。

...ポインタ...何か間違ったことをしている場合...

はい、あなたは何か間違ったことをしています... Valgrindは、OSでほとんど壊れていると言っていますが、ここで質問する前に、合理的なプログラマーが取るすべてのオプションをなんとかバイパスしました。

  1. 不安定なものではなく、安定したメモリプロファイラー（OSと互換性がある）を取得し、そのプロファイラー（/usr/bin/leaksおよび/usr/bin/malloc_history、または「XCodeInstruments」）を使用してリークを検証します。
  2. それが利用できない場合は、LinuxまたはFreeBSDを仮想マシンにインストールし、そこでvalgrindを実行すると、安定します。

質問がこれら2つの選択肢のいずれかから出力された場合、その警告は表示されず、壊れた/紛らわしい出力が表示されない可能性があります。おそらく、プログラムにリークがないことを示している可能性があります。その場合、プログラムがメモリリークのせいになる可能性が低いため、少し心配する必要はありません。おそらく、プログラムが関数xxxでメモリをリークし、関数で割り当てられていることを示している可能性があります。この場合、これらのリークを自分で診断して修正できるため、少し心配する必要はありません。

于 2013-03-25T12:41:13.297 に答える