[teo1747]

Contains the time-slicing commit as its base: merge the time-slicing PR first, after which this diff shows only the _DEFINE change.

This is the cross-type _DEFINE change deferred in A40 (API-021, KRN-OBJ-009). Each macro declares storage and the handle, and registers an init-table wrapper that constructs the object in emb_kernel_init(), as EMB_THREAD_DEFINE does. A construction failure faults through emb_check_status().

Macro	Positional fields
EMB_SEM_DEFINE	initial, max
EMB_MUTEX_DEFINE	protocol, ceiling, flags
EMB_EVENT_DEFINE	initial, flags
EMB_COND_DEFINE	flags
EMB_MSGQ_DEFINE	item_size, capacity, flags (defines the ring)
EMB_WORKQ_DEFINE	priority, stack_size (defines the stack)
EMB_TIMER_DEFINE	fn, arg; interrupt-context timers only

A64 records the contract:

• The macros take positional fields: an attribute initializer would zero fields whose defaults are not zero.
• The table entry stays one wrapper pointer.
• A work-queue timer is not covered. Table entries, the system queue's included, run in link order and EMB_INIT_AFTER does not exist yet, so such a timer is constructed in code (SPEC-009 §5.2 already says so).
• Names are kept only with CONFIG_EMB_OBJ_NAMES, so AVR does not copy the literals to RAM.

Evidence

• One *_define_constructs_in_init_table conformance case per type.
• Local runs, all passing:
  • native gcc/clang/release/tiny/periodic/timeslice/timeslice-tickless;
  • QEMU cm3, cm4 ×3, rv32 ×3;
  • AVR uno ×3; on AVR and RISC-V the per-case output confirms the cases ran;
  • asan/tsan/coverage and EmbSIM ×3.
• The docs build has the 9 known shim warnings; check-banned and generate --check are clean.

Docs

API-021, SPEC-001 §6.4, SPEC-009 §5.2, the synchronization guide and CHANGELOG.