[TF-M] Alignment issues on stack with ITS

ITS defines a few structs with specific alignment requirements, like:

struct __attribute__((__aligned__(ITS_FLASH_MAX_ALIGNMENT))) its_file_meta_t {     uint32_t lblock;               /*!< Logical datablock where file is                                     *   stored                                     */     size_t data_idx;               /*!< Offset in the logical data block */     size_t cur_size;               /*!< Size in storage system for this #                                     *   fragment                                     */     size_t max_size;               /*!< Maximum size of this file */     uint32_t flags;                /*!< Flags set when the file was created */     uint8_t id[ITS_FILE_ID_SIZE];  /*!< ID of this file */ };

This causes issues with the IAR compiler when these structs are declared as autos:

static psa_status_t its_mblock_copy_remaining_block_meta(                                               struct its_flash_fs_ctx_t *fs_ctx,                                               uint32_t lblock) {     struct its_block_meta_t block_meta;     psa_status_t err;     uint32_t meta_block;     size_t pos;     uint32_t scratch_block;     size_t size; ...

The IAR compiler gives these errors if the alignment is 0x10 (the stack is 8 byte aligned):

struct its_block_meta_t block_meta;                               ^ "C:\Users\thomasto\Projects\tf-m1\trusted-firmware-m\secure_fw\partitions\internal_trusted_storage\flash_fs\its_flash_fs_mblock.c",415 Error[Ta121]:           Auto variable "block_meta" cannot have a stricter alignment than the           stack

I assume this alignment is only required for the flash, so the alignment attributes should be set when declaring variables in the flash, not on the type.

Comments?

Cheers, Thomas