diff --git a/sadump.c b/sadump.c
index 490eb6c..92573bf 100644
--- a/sadump.c
+++ b/sadump.c
@@ -37,7 +37,7 @@ static inline int is_set_bit(char *bitmap, ulong pfn);
 static inline int page_is_ram(unsigned int nr);
 static inline int page_is_dumpable(unsigned int nr);
 static int lookup_diskset(ulong whole_offset, int *diskid, ulong *disk_offset);
-static struct tm *efi_time_t_to_tm(const efi_time_t *e, struct tm *t);
+static struct tm *efi_time_t_to_tm(const efi_time_t *e);
 static char * guid_to_str(efi_guid_t *guid, char *buf, size_t buflen);
 static int verify_magic_number(uint32_t magicnum[DUMP_PART_HEADER_MAGICNUM_SIZE]);
 static ulong per_cpu_ptr(ulong ptr, int cpu);
@@ -279,19 +279,17 @@ restart:
 
 		if (memcmp(&sph->time_stamp, &smh->time_stamp,
 			   sizeof(efi_time_t)) != 0) {
-			struct tm tm;
-			if (CRASHDEBUG(1))
-				error(INFO, "sadump: time stamp mismatch\n"
-				      "  partition header: %s\n"
-				      "  media header: %s\n",
+			if (CRASHDEBUG(1)) {
+				error(INFO, "sadump: time stamp mismatch\n");
+				error(INFO, "sadump:   partition header: %s\n",
 				      strip_linefeeds(asctime
 						      (efi_time_t_to_tm
-						       (&sph->time_stamp,
-							&tm))),
+						       (&sph->time_stamp))));
+				error(INFO, "sadump:   media header: %s\n",
 				      strip_linefeeds(asctime
 						      (efi_time_t_to_tm
-						       (&smh->time_stamp,
-							&tm))));
+						       (&smh->time_stamp))));
+			}
 			goto err;
 		}
 
@@ -538,18 +536,20 @@ add_disk(char *file)
 
 	if (memcmp(&sd->header->time_stamp, &ph->time_stamp,
 		   sizeof(efi_time_t)) != 0) {
-		struct tm tm;
-		if (CRASHDEBUG(1))
-			error(INFO, "sadump: time stamp mismatch\n"
-			      "  partition header on disk #1: %s\n"
-			      "  partition header on disk #%d: %s\n",
-			      strip_linefeeds(asctime(efi_time_t_to_tm
-						      (&sd->header->time_stamp,
-						       &tm))),
+		if (CRASHDEBUG(1)) {
+			error(INFO, "sadump: time stamp mismatch\n");
+			error(INFO,
+			      "sadump:   partition header on disk #1: %s\n",
+			      strip_linefeeds(asctime
+					      (efi_time_t_to_tm
+					       (&sd->header->time_stamp))));
+			error(INFO,
+			      "sadump:   partition header on disk #%d: %s\n",
 			      diskid+1,
-			      strip_linefeeds(asctime(efi_time_t_to_tm
-						      (&ph->time_stamp,
-						       &tm))));
+			      strip_linefeeds(asctime
+					      (efi_time_t_to_tm
+					       (&ph->time_stamp))));
+		}
 		free(ph);
 		return FALSE;
 	}
@@ -794,30 +794,31 @@ ulong get_sadump_switch_stack(ulong task)
 }
 
 static struct tm *
-efi_time_t_to_tm(const efi_time_t *e, struct tm *t)
+efi_time_t_to_tm(const efi_time_t *e)
 {
+	static struct tm t;
 	time_t ti;
 
-	memset(t, 0, sizeof(*t));
+	memset(&t, 0, sizeof(t));
 
-	t->tm_sec  = e->second;
-	t->tm_min  = e->minute;
-	t->tm_hour = e->hour;
-	t->tm_mday = e->day;
-	t->tm_mon  = e->month - 1;
-	t->tm_year = e->year - 1900;
+	t.tm_sec  = e->second;
+	t.tm_min  = e->minute;
+	t.tm_hour = e->hour;
+	t.tm_mday = e->day;
+	t.tm_mon  = e->month - 1;
+	t.tm_year = e->year - 1900;
 
 	if (e->timezone != EFI_UNSPECIFIED_TIMEZONE)
-		t->tm_hour += e->timezone;
+		t.tm_hour += e->timezone;
 
 	else if (CRASHDEBUG(1))
 		error(INFO, "sadump: timezone information is missing\n");
 
-	ti = mktime(t);
+	ti = mktime(&t);
 	if (ti == (time_t)-1)
-		return t;
+		return &t;
 
-	return localtime_r(&ti, t);
+	return localtime_r(&ti, &t);
 }
 
 static char *
@@ -867,7 +868,6 @@ int sadump_memory_dump(FILE *fp)
 	struct sadump_header *sh;
 	struct sadump_media_header *smh;
 	int i, others;
-	struct tm tm;
 	char guid[33];
 
 	fprintf(fp, "sadump_data: \n");
@@ -908,7 +908,7 @@ int sadump_memory_dump(FILE *fp)
 	fprintf(fp, "         disk_set_id: %s\n", guid_to_str(&sph->disk_set_id, guid, sizeof(guid)));
 	fprintf(fp, "              vol_id: %s\n", guid_to_str(&sph->vol_id, guid, sizeof(guid)));
 	fprintf(fp, "          time_stamp: %s\n",
-		strip_linefeeds(asctime(efi_time_t_to_tm(&sph->time_stamp, &tm))));
+		strip_linefeeds(asctime(efi_time_t_to_tm(&sph->time_stamp))));
 	fprintf(fp, "        set_disk_set: %u\n", sph->set_disk_set);
 	fprintf(fp, "             reserve: %u\n", sph->reserve);
 	fprintf(fp, "         used_device: %llu\n", (ulonglong)sph->used_device);
@@ -922,7 +922,7 @@ int sadump_memory_dump(FILE *fp)
 	fprintf(fp, "      header_version: %u\n", sh->header_version);
 	fprintf(fp, "             reserve: %u\n", sh->reserve);
 	fprintf(fp, "           timestamp: %s\n",
-		strip_linefeeds(asctime(efi_time_t_to_tm(&sh->timestamp, &tm))));
+		strip_linefeeds(asctime(efi_time_t_to_tm(&sh->timestamp))));
 	fprintf(fp, "              status: %u\n", sh->status);
 	fprintf(fp, "            compress: %u\n", sh->compress);
 	fprintf(fp, "          block_size: %u\n", sh->block_size);
@@ -998,7 +998,7 @@ int sadump_memory_dump(FILE *fp)
 		fprintf(fp, "\n           sadump_id: %s\n", guid_to_str(&smh->sadump_id, guid, sizeof(guid)));
 		fprintf(fp, "         disk_set_id: %s\n", guid_to_str(&smh->disk_set_id, guid, sizeof(guid)));
 		fprintf(fp, "          time_stamp: %s\n",
-			strip_linefeeds(asctime(efi_time_t_to_tm(&smh->time_stamp, &tm))));
+			strip_linefeeds(asctime(efi_time_t_to_tm(&smh->time_stamp))));
 		fprintf(fp, "      sequential_num: %d\n", smh->sequential_num);
 		fprintf(fp, "           term_cord: %d\n", smh->term_cord);
 		fprintf(fp, "disk_set_header_size: %d\n", smh->disk_set_header_size);
@@ -1039,7 +1039,7 @@ int sadump_memory_dump(FILE *fp)
 		fprintf(fp, "           disk_set_id: %s\n", guid_to_str(&sph->disk_set_id, guid, sizeof(guid)));
 		fprintf(fp, "                vol_id: %s\n", guid_to_str(&sph->vol_id, guid, sizeof(guid)));
 		fprintf(fp, "            time_stamp: %s\n",
-			strip_linefeeds(asctime(efi_time_t_to_tm(&sph->time_stamp, &tm))));
+			strip_linefeeds(asctime(efi_time_t_to_tm(&sph->time_stamp))));
 		fprintf(fp, "          set_disk_set: %u\n", sph->set_disk_set);
 		fprintf(fp, "               reserve: %u\n", sph->reserve);
 		fprintf(fp, "           used_device: %llu\n", (ulonglong)sph->used_device);