Do not use unsafe to take address of slice element

[zikaeroh]

Fixes #254.

Changes proposed in this pull request:

• Don't use unsafe to take the address of a slice element, as suggested in: runtime error: unsafe pointer arithmetic (Go 1.14 checkptr) #254 (comment)

Note that this still doesn't make this repo pass in -race mode (which should really be looked into).

[coveralls]

Coverage decreased (-0.8%) to 89.071% when pulling 1d698ba on zikaeroh:fix-254 into c6266f4 on yuin:master.

[coveralls]

Coverage decreased (-1.07%) to 88.757% when pulling 1d698ba on zikaeroh:fix-254 into c6266f4 on yuin:master.

[tul]

I tested this change and it still allocates the floats correctly from the block as far as I can see, so this looks good to me +1

[epikur-io]

I also tested this. Works great and makes the code much cleaner