const runtime.mallocHeaderSize

5 uses

	runtime (current package)
		malloc.go#L124: 	mallocHeaderSize       = gc.MallocHeaderSize
		malloc.go#L2000: 		v -= mallocHeaderSize
		malloc.go#L2003: 		size += mallocHeaderSize
		malloc.go#L2120: 	if size < maxTinySize || size > maxSmallSize-mallocHeaderSize {
		runtime2.go#L738: 	_ [(1 - goarch.IsWasm) * (2048 - mallocHeaderSize - mRedZoneSize - unsafe.Sizeof(m{}))]byte