C 终端上的内存分配第一次编译错误

我正在malloc实验室项目中工作，我需要找到效用和吞吐量的性能指标。我能够获得输出效率，但第一次执行时有一个问题

我已经给出了一组特定的文件，其中包括跟踪和其他文件，当我第一次尝试运行程序时，它会显示错误，但是当我第二次使用同一命令运行同一代码到多次时，我没有得到错误，输出是否正常？为什么第一次运行时显示错误？在malloc中分配内存或执行操作是否有问题

命令和第一次错误如下所示

enter code here
@ubuntu:$ make

enter code here
gcc -Wall -O2 -m32   -c -o mdriver.o mdriver.c
mdriver.c: In function ‘remove_range’:
mdriver.c:438:9: warning: variable ‘size’ set but not used [-Wunused-but-set-variable]
 int size;
     ^
mdriver.c: In function ‘read_trace’:
mdriver.c:498:11: warning: ignoring return value of ‘fscanf’, declared with attribute   warn_unused_result [-Wunused-result]
 fscanf(tracefile, "%d", &(trace->sugg_heapsize)); /* not used */
       ^
mdriver.c:499:11: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result]
fscanf(tracefile, "%d", &(trace->num_ids));     
       ^
mdriver.c:500:11: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result]
fscanf(tracefile, "%d", &(trace->num_ops));     
       ^
mdriver.c:501:11: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result]
fscanf(tracefile, "%d", &(trace->weight));        /* not used */
       ^
mdriver.c:524:12: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result]
fscanf(tracefile, "%u %u", &index, &size);
        ^
mdriver.c:531:12: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result]
fscanf(tracefile, "%u %u", &index, &size);
        ^
mdriver.c:538:12: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result]
fscanf(tracefile, "%ud", &index);
        ^
gcc -Wall -O2 -m32   -c -o mm.o mm.c
mm.c:780:13: warning: ‘mm_check’ defined but not used [-Wunused-function]
static int mm_check(void)
         ^
gcc -Wall -O2 -m32   -c -o memlib.o memlib.c
gcc -Wall -O2 -m32   -c -o fsecs.o fsecs.c
gcc -Wall -O2 -m32   -c -o fcyc.o fcyc.c
gcc -Wall -O2 -m32   -c -o clock.o clock.c
gcc -Wall -O2 -m32   -c -o ftimer.o ftimer.c
gcc -Wall -O2 -m32 -o mdriver mdriver.o mm.o memlib.o fsecs.o fcyc.o clock.o ftimer.o

当我第一次运行时，我得到如下错误：

enter code here
@ubuntu:$ make

enter code here
gcc -Wall -O2 -m32   -c -o mdriver.o mdriver.c
mdriver.c: In function ‘remove_range’:
mdriver.c:438:9: warning: variable ‘size’ set but not used [-Wunused-but-set-variable]
 int size;
     ^
mdriver.c: In function ‘read_trace’:
mdriver.c:498:11: warning: ignoring return value of ‘fscanf’, declared with attribute   warn_unused_result [-Wunused-result]
 fscanf(tracefile, "%d", &(trace->sugg_heapsize)); /* not used */
       ^
mdriver.c:499:11: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result]
fscanf(tracefile, "%d", &(trace->num_ids));     
       ^
mdriver.c:500:11: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result]
fscanf(tracefile, "%d", &(trace->num_ops));     
       ^
mdriver.c:501:11: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result]
fscanf(tracefile, "%d", &(trace->weight));        /* not used */
       ^
mdriver.c:524:12: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result]
fscanf(tracefile, "%u %u", &index, &size);
        ^
mdriver.c:531:12: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result]
fscanf(tracefile, "%u %u", &index, &size);
        ^
mdriver.c:538:12: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result]
fscanf(tracefile, "%ud", &index);
        ^
gcc -Wall -O2 -m32   -c -o mm.o mm.c
mm.c:780:13: warning: ‘mm_check’ defined but not used [-Wunused-function]
static int mm_check(void)
         ^
gcc -Wall -O2 -m32   -c -o memlib.o memlib.c
gcc -Wall -O2 -m32   -c -o fsecs.o fsecs.c
gcc -Wall -O2 -m32   -c -o fcyc.o fcyc.c
gcc -Wall -O2 -m32   -c -o clock.o clock.c
gcc -Wall -O2 -m32   -c -o ftimer.o ftimer.c
gcc -Wall -O2 -m32 -o mdriver mdriver.o mm.o memlib.o fsecs.o fcyc.o clock.o ftimer.o

我再次运行相同的命令

enter code here
@ubuntu:$ make
make: `mdriver' is up to date.

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现在，它没有显示错误，之后，如果我用所需的命令运行程序，它工作得很好，但它第一次显示错误

您的源代码中没有错误。有很多警告。即使源有警告，也会生成对象和可执行文件。在makefile中，如果时间戳保持不变，则不会重新编译文件

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为了更好地理解，请在源代码中插入一些编译错误，并反复运行make命令，这样您就可以理解其中的区别。

错误来自一个名为mdriver.c的文件，该文件是我的教授提供的，我不必修改它，问题是我真的很困惑如何消除这些警告！！我试图更改make文件中的某些内容，但没有帮助@Dvlop尝试制作-s。它将超越印刷品。然后分享错误信息。到目前为止，我在你的帖子中找不到错误信息。尝试简化您的问题并再次发布。您有两个选项：修复产生警告的代码，禁用警告。如果您选择b，请准备好承担后果：