looks like does not follow branching

[dkropachev]

	var cols []ColumnInfo
	if meta.colCount < 1000 {
		// preallocate columninfo to avoid excess copying
		cols = make([]ColumnInfo, meta.colCount)
		for i := 0; i < meta.colCount; i++ {
			f.readCol(&cols[i], &meta, globalSpec, keyspace, table)
		}
	} else {
		// use append, huge number of columns usually indicates a corrupt frame or
		// just a huge row.
		for i := 0; i < meta.colCount; i++ {
			var col ColumnInfo
			f.readCol(&col, &meta, globalSpec, keyspace, table)
			cols = append(cols, col)
		}
	}

throws:

frame.go:1119:11: append to slice `cols` with non-zero initialized length (makezero)
                        cols = append(cols, col)

[m-ocean-it]

Here's a simplified version of the code that also triggers that false-positive without using the -always flag:

func foo(colCount int) {
	var cols []int
	if colCount < 1000 {
		cols = make([]int, colCount)
	} else {
		for n := range 100 {
			cols = append(cols, n)
		}
	}
}

[m-ocean-it]

@dkropachev For now, you can put //nozero on the problematic line to silence the warning.

[brandon1024]

This tripped me up today as well. I've got a similar setup to @dkropachev, and makezero reports a false positive.

	switch DataType {
	case IntegerUnsigned, IntegerSigned, Float:
		var payload PropertyPayload[float64]
		err = c.get(sig, &payload)

		raw = make([]byte, 8)                  // <-------- because of this   
		binary.BigEndian.PutUint64(raw, math.Float64bits(payload.Value))
	case Boolean:
		var payload PropertyPayload[bool]
		err = c.get(sig, &payload)

		if payload.Value {
			raw = append(raw, 0xFF)            // <-------- false positive here
		} else {
			raw = append(raw, 0x00)            // <-------- false positive here
		}
	case String:
		var payload PropertyPayload[string]
		err = c.get(sig, &payload)

		raw = []byte(payload.Value)
	default:
		err = fmt.Errorf("comm: unsupported data type '%s' for signal '%s'", DataType, sig)
	}