C RESOURCE_LEAK false positive appears to be caused by calls to stat() or fstat() #1351

mherunter@IGCA180701-Linux:~$ infer --version
Infer version v0.17.0
Copyright 2009 - present Facebook. All Rights Reserved.

mherunter@IGCA180701-Linux:~$ lsb_release -a
No LSB modules are available.
Distributor ID:	Ubuntu
Description:	Ubuntu 18.04.2 LTS
Release:	18.04
Codename:	bionic

mherunter@IGCA180701-Linux:~/Firmware/tests/infer$ make clean && infer run -- make
rm -f test
Capturing in make/cc mode...
gcc -Wall -O2 -o test test.c
Found 1 source file to analyze in /home/mherunter/Firmware/tests/infer/infer-out


Analysis finished in 359mss

Found 1 issue

test.c:18: error: RESOURCE_LEAK
  resource of type `_IO_FILE` acquired by call to `fopen()` at line 13, column 13 is not released after line 18, column 2.
  16.   		return 1;
  17.   	}
  18. > 	fp = check_file_size_and_reopen(fp);
  19.   
  20.   	if (fp) {


Summary of the reports

  RESOURCE_LEAK: 1

#include <stdio.h>
#include <sys/stat.h>
#include <unistd.h>

#define FILE_MAX_SIZE	256000
#define FILE_NAME		"dump.log"
#define LAST_FILE_NAME	"dump.log2"

FILE* check_file_size_and_reopen(FILE* fp);

int main(void) {

	FILE *fp = fopen(FILE_NAME, "a+");

	if (!fp) {
		return 1;
	}
	fp = check_file_size_and_reopen(fp);

	if (fp) {
		fclose(fp);
	}

	return 0;
}

FILE* check_file_size_and_reopen(FILE* fp) {
	struct stat info;
	int fd = fileno(fp);
	(void)fd;

	fstat(fd, &info);

	if (info.st_size <= FILE_MAX_SIZE) {
		return fp;	
	}

	fclose(fp);
	rename(FILE_NAME, LAST_FILE_NAME);

	return fopen(FILE_NAME,"a+");
}