Blender Git Loki

Cycles: Fix undefined behavior which can causes crashes with a misaligned address error

Cycles casts a pointer from ShaderDataTinyStorage to ShaderData, these structs by default had different alignments however (the former was 1-byte aligned, the latter 16-byte). This caused undefined behavior on at least the CUDA platform. Forcing both structs to use the same alignment fixes this.

CUDA toolkits newer than 10.1 run into this because of a compiler optimization.

Reviewed By: brecht

Differential Revision: https://developer.blender.org/D5883