Structs in the code, for instance internal and global variables, are disaggregated by default and decomposed into their member elements, as described in Structs. The number and type of elements created are determined by the contents of the struct itself. Arrays of structs are implemented as multiple arrays, with a separate array for each member of the struct.
Structs in C/C++ are padded with extra bytes by the compiler for data alignment.
In order to make kernel code in Vitis HLS compliant
gcc, structs in kernel code are padded with extra
bytes. Padding and alignment can be changed as described in Struct Padding and Alignment.