count在表中没有数据的时候偶现panic

[allen7fu]

Description

        tx := db.Begin()
	defer tx.Commit()
	var total int32
	if err := tx.Table(constant.Tbl).Where(query, where.Args...).Count(&total).Error; err != nil {
		return 0, nil, err
	}

	if total == 0 {
		return total, result, nil
	}

	if err := tx.Table(constant.Tbl).Where(query, where.Args...).Order("priority desc").Limit(limit).Offset(offset).Find(&result).Error; err != nil {
		return 0, nil, err
	}

	return total, result, nil

本意是，保证count和分页数据的一致性，在select下起了一个事务，会偶现panic，堆栈如下

panic: runtime error: invalid memory address or nil pointer dereference [recovered]
	panic: runtime error: invalid memory address or nil pointer dereference [recovered]
	panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x40 pc=0x10087d3e2]

goroutine 155 [running]:
testing.tRunner.func1.2({0x100ff0260, 0x101e9f360})
	/usr/local/go/src/testing/testing.go:1526 +0x24e
testing.tRunner.func1()
	/usr/local/go/src/testing/testing.go:1529 +0x39f
panic({0x100ff0260, 0x101e9f360})
	/usr/local/go/src/runtime/panic.go:884 +0x213
database/sql.(*Tx).rollback(0x10010db01?, 0x0?)
	/usr/local/go/src/database/sql/sql.go:2282 +0x22
database/sql.(*Tx).Rollback(0x1013b77c8?)
	/usr/local/go/src/database/sql/sql.go:2314 +0x1b
github.com/jinzhu/gorm.(*Scope).callCallbacks.func1()
	/Users/xxx/go/pkg/mod/github.com/jinzhu/[email protected]/scope.go:863 +0x7d
panic({0x100ff0260, 0x101e9f360})
	/usr/local/go/src/runtime/panic.go:884 +0x213
database/sql.(*Tx).grabConn(0x0, {0x1013cf2f8, 0xc00004a140})
	/usr/local/go/src/database/sql/sql.go:2209 +0x52
database/sql.(*Tx).QueryContext(0x0, {0x1013cf2f8, 0xc00004a140}, {0xc000da6e60, 0x50}, {0xc0007aabf0, 0x1, 0x1})
	/usr/local/go/src/database/sql/sql.go:2485 +0x57
database/sql.(*Tx).QueryRowContext(...)
	/usr/local/go/src/database/sql/sql.go:2508
database/sql.(*Tx).QueryRow(0xc000ce5900?, {0xc000da6e60?, 0x10?}, {0xc0007aabf0?, 0xc0007aab60?, 0x100f042e0?})
	/usr/local/go/src/database/sql/sql.go:2522 +0x4a
github.com/jinzhu/gorm.rowQueryCallback(0xc000ce5900)
	/Users/xxx/go/pkg/mod/github.com/jinzhu/[email protected]/callback_row_query.go:36 +0x24a
github.com/jinzhu/gorm.(*Scope).callCallbacks(0xc000ce5900, {0xc0002a2d80, 0x1, 0x100f042e0?})
	/Users/xxx/go/pkg/mod/github.com/jinzhu/[email protected]/scope.go:869 +0x99
github.com/jinzhu/gorm.(*Scope).row(0xc000ce5900)
	/Users/xxx/go/pkg/mod/github.com/jinzhu/[email protected]/scope.go:945 +0xf6
github.com/jinzhu/gorm.(*Scope).count(0xc000ce5900, {0x100f14d60, 0xc0000efee4})
	/Users/xxx/go/pkg/mod/github.com/jinzhu/[email protected]/scope.go:1034 +0x510
github.com/jinzhu/gorm.(*DB).Count(0x1011e0f61?, {0x100f14d60, 0xc0000efee4})
	/Users/xxx/go/pkg/mod/github.com/jinzhu/[email protected]/main.go:401 +0x45

gorm版本：v1.9.16
复现条件：
1）表中没有数据
2）循环调用10000次，大概3000次的时候panic

[github-actions]

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