Compile target: ARM32 Linux

• Type: feature
• Status: done
• Owner: claude
• Blocked-by: feature-target-aarch64
• Unblocks: feature-target-esp32, feature-additional-cpu-targets
• Opened: 2026-06-06 (user request; roadmap.md Phase 4)

Motivation

ARM32 (Raspberry Pi 2/3, older Pi) extends the ARM work to the 32-bit ABI and brings the toolchain a step closer to the embedded/bare-metal entry point.

Scope

Per ../../developer/roadmap.md Phase 4:

• ARM32 (ARMv7-A) register set, EABI calling convention, 32-bit pointers.
• Thumb vs ARM instruction-set decision.
• ARM32 ELF emission and Linux syscall ABI.

Acceptance

ARM32 output runs on an ARMv7 Linux host (e.g. Pi 2/3); the suite passes; the build meets the fixedpoint gate for the ARM32 target.

Dependency note

Blocked-by feature-target-aarch64 reflects shared ARM backend infrastructure + roadmap staging, not a hard requirement. Move to urgent/ to pull it forward.

Log

• 2026-06-06 — ticket opened from user request + roadmap Phase 4.
• 2026-06-10 — ticket claimed; starting implementation of ARM32 target support.
• 2026-06-11 — completed ARM32 Linux target slice. make test-arm32 passes under tools/run_target.sh arm32 with output identical to x86-64 for hello, arithmetic, procedures, loops, writes, var/out params, raw syscalls, and heap allocation/free including pointer dereference, record fields, and static array indexing (test/test_cross_heap.pas). Added ARM32 stack-argument support for helper procedures with more than four parameters and enabled the Pascal builtinheap allocator path. Commit: e15bd4f.
• 2026-06-11 — added ARM32 managed AnsiString support. The backend now lowers literal/char/inline-string conversion, retain/release assignment, by-ref store publishing, concat/equality through PXXStr* Pascal helpers, string writes, pointer-sized string returns, local string cleanup, IR_SLOTADDR, and inline tyString stack-buffer concat. Fixed two ARM32-specific issues found during validation: x86-64 managed-local zeroing bytes in ARM32 procedures, and invalid large ARM immediate encoding for the 272-byte inline string buffer. Added test/test_cross_string.pas to make test-arm32.