[borisbat]

Behavior change: an assert over a field of an effectful call, or over an inserting table index, is now a compile error naming the side effect - write it as verify. Character and string literals take the C escape set, so '\a', '\v', '\?', '\xHH' and '\NNN' lex where they were errors.

Why. Seven of lookibed's optimizer and front-end reports: an unused call was dropped together with the addr(arr[i++]), computed index or field of a call result it carried; a constant-argument call into mutual recursion that reads a global was folded; a private function shaped while (true) { ...; while (true) { return } } looped forever once inlined; a property compound assignment on deref(p + k) crashed context relocation; tuple<void?> reused the tuple<int?> instance or reported two; reinterpret<int?>(f()) of a uint64 extern threw in the interpreter; the lexers lacked half the C escapes.

What changes.

• A field, index or safe-index node carries the side effects of its operands, so an unused call keeps them and an assert over them reports.
• Inferred side effects close over call cycles: a function in a cycle takes the cycle's union, not the partial flags the walk saw mid-cycle.
• An inlined return out of a loop that ends a loop body leaves the outer loop too.
• A property compound assignment gives its setter its own copy of the base; a with-scoped property copies the with value the same way.
• An explicit type argument never takes the void? stand-in, so each pointer instance is its own.
• A reinterpret across eval slots reads its operand through eval instead of the typed slot the extern does not answer.
• '\0', '\a', '\v', '\"', '\?', '\xHH' and '\NNN' lex in both lexers through one escape rule per suffix; a string literal takes the same set and an embedded \0 ends it; the tree-sitter scanner reads the same set.

Observable behavior.

• assert(f().x) with an effectful f, or assert(tab[k]) on a mutable table: silently kept or dropped -> compile error naming the side effect.
• let r = mutual_a(3) where the cycle reads a global: folded to the wrong constant -> evaluated.
• The nested-while private function: infinite loop under auto-inline -> returns.
• obj.prop += 1 with obj = deref(p + k): crash in context relocation -> runs.
• tuple<void?> beside tuple<int?>: wrong instance or multiple instances -> its own instance.
• reinterpret<int?>(f()) of a uint64 extern: interpreter throw -> the value.
• '\a', '\?', "\x41": lexer error -> the character.

Where to look. inheritEffects and closeCallCycles in src/ast/ast_unused.cpp; the escape rules in src/parser/ds2_lexer.lpp and ds_lexer.lpp; scan_escape in tree-sitter-daslang/src/scanner.c.

Fixes #4458, fixes #4460, fixes #4464, fixes #4449, fixes #4452, fixes #4457, fixes #4465.

Validation, claims, ledger

Validation

• Full AOT sweep (preflight --only tests-aot, the test_aot build and sweep over tests/) passed at the final tip, rebased on dasLLVM: bool and pointer reinterprets, default<T[N]>, try/recover return, inline ptr_diff, speculatable lookups, --jit-remarks #4472's merge, 760 s; per-PR CI builds only the subset. Every other gate and lane passed at the same tip: lint, review-md, md-ascii, hash-refs, cpp-syntax, ast-verify, compile-sweep, tests-cpp, tests-interp, tests-jit, utils-tests.
• Two codex review rounds, one at the audited tip and one at the final tip after the fix batch: no findings in either, every changed file in both traces.
• OBSERVABLE_EFFECTS (src/ast/ast.cpp), the one citer of the changed ARCHITECTURE_EFFECTS.md section: the flag set it names is unchanged; the new paragraph documents the cycle closure beside it.
• The local docs/digest gate is red on this tree for a reason outside the diff: the generator writes no function-* detail file for the core daslib modules on this box (algorithm, fio, ...), so the regenerated digest loses 113 one-line descriptions that the shipped digest took from stale, gitignored detail files; the main tree shows the same with master's binary. The shipped digest is not touched. docs/sphinx-html is the known sphinx_sitemap environment red.

Claims - stated, not tested

• The noNativeSideEffects half of the effect inheritance has no test: its only consumer is the aot_order_side_effects lint, which defaults off and no test enables.
• The tree-sitter scanner's octal digit limits and its rejection of '\x without a digit are not observable in the corpus (string content nodes are hidden); the corpus covers every accepted escape form.
• The scanner's and the compiler's escape sets agree by construction (the scanner comment names CHAR_ESCAPE as its source); no test diffs the two.

Not done

• The src/ast/REVIEW.md self-review items (the REVIEW.das rule's trailing sentence, the no_promo example list, the version-bump rule's trigger) are fixed on the JIT branch (dasLLVM: bool and pointer reinterprets, default<T[N]>, try/recover return, inline ptr_diff, speculatable lookups, --jit-remarks #4472), which edits the same file; this PR does not repeat them.
• The regenerated lexer .cpp files carry the local flex build's #line preamble.
• tests/REVIEW.md gains the daslang-child cache rule on the JIT branch (dasLLVM: bool and pointer reinterprets, default<T[N]>, try/recover return, inline ptr_diff, speculatable lookups, --jit-remarks #4472); this PR applies it (-no-module-cache on the spawned child) without restating it.
• Checklist self-review items left as found, each its own restructure: tests/REVIEW.md's AOT trigger describes two sets and its module-cache routing and placement rules repeat one trigger; src/REVIEW.md's narrow-path rule restates what its gate checks and its opening routes by folder; daslib/REVIEW.md's pair-record duty covers only the daslib side and two of its rules describe the system; include/daScript/simulate/REVIEW.md's hot-path rule is keyed to a changed body and its ledger rule fuses two duties; include/daScript/ast/REVIEW.md's layout rule lists layout changes instead of naming the property; the root REVIEW.md's modules/<M> route keys on a folder name a require line never spells and its routed_paths sync duty runs one way.

#nightly - the diff touches src/ and include/ and regenerates the lexers.

[Copilot]

Note

Copilot was unable to complete this review at the selected tier due to model policy or plan restrictions.

🔵 Needs a closer look

The change spans multiple high-risk core compiler subsystems (optimizer side-effects, const folding/inlining, interpreter eval slots, type identity, and lexer/tree-sitter/serializer behavior) with user-visible semantics, making it difficult to validate safely from the diff without maintainer review and broad CI/runtime verification.

No open issues 🎉

What changed in this PR

This pull request fixes multiple correctness issues across the optimizer, type/instance handling, interpreter simulation, and lexer/tooling parity, and expands character/string literal escaping to match the C escape set (compiler lexers + tree-sitter), with regressions and documentation updates.

Changes:

• Preserve and properly close inferred side effects (including through field/index/safe-index nodes and across call cycles) to prevent incorrect dropping/folding and improve diagnostics (e.g., assert over effectful access).
• Fix inlining control-flow for nested loop returns, property compound-assignment lowering stability, explicit-type generic instance separation (notably void? pointer-like shapes), and interpreter reinterpret handling across eval slots.
• Expand and unify literal escape handling (\a, \v, \?, \xHH, \NNN, etc.) across compiler lexers and tree-sitter, with tests, canaries, docs, and changelog entries.

File	Summary
tree-sitter-daslang/​test/​corpus/​literals.txt	Adds corpus coverage for expanded C-style escapes in char/string literals.
tree-sitter-daslang/​src/​scanner.c	Updates tree-sitter external scanner to recognize expanded escape forms (octal/hex + additional C escapes).
tree-sitter-daslang/​REVIEW.md	Updates review/checklist guidance for scanner changes (requires corpus/canary coverage).
tests/​watchdog/​test_watchdog.das	Switches watchdog timing/guard logic to shared child_deadline helper usage.
tests/​strings/​test_cpp_functions.das	Adds/adjusts regression assertions around escape handling in safe_unescape.
tests/​README.md	Registers new/updated tests and fixtures in the test index.
tests/​language/​test_reinterpret_extern_result.das	Adds regression tests for reinterpret behavior on extern-return values.
tests/​language/​test_property_compound_assign_deref_offset.das	Adds regression tests for property += with deref(p + k) and with bases.
tests/​language/​test_nested_while_private.das	Adds regression coverage for nested while(true) private function return behavior under inlining.
tests/​language/​test_generic_tuple_void_ptr.das	Adds tests ensuring tuple<void?> (and related) instantiates distinctly vs other pointer-like shapes.
tests/​language/​test_fold_mutual_recursion_global.das	Adds regression preventing incorrect const-folding through call cycles that read globals.
tests/​language/​test_char_escapes.das	Adds gen2 tests for expanded escape set and string NUL-termination behavior.
tests/​language/​test_char_escapes_gen1.das	Adds gen1 tests for expanded escape set.
tests/​language/​test_addr_argument_side_effects.das	Adds regression tests ensuring operand side effects are preserved through addr/index/field expressions.
tests/​language/​failed_assert_over_effectful_field.das	Adds negative test validating assert over effectful field access is rejected with a side-effect-specific error.
tests/​language/​_fixture_nested_while_private.das	Adds fixture program used by the nested-while private regression test.
tests/​fio/​test_process.das	Switches process-test deadlines/guards to shared child_deadline helper usage.
tests/​fio/​fio_poll.das	Switches poll-test deadlines/guards to shared child_deadline helper usage.
tests/​aot/​CMakeLists.txt	Updates AOT subset module list (adds daslib/fio.das).
src/​simulate/​simulate_visit.cpp	Extends simulate visitor support for new reinterpret-slot simulation node.
src/​simulate/​runtime_string.cpp	Factors/extends shared character escape decoding and integrates it into runtime unescape paths.
src/​REVIEW.md	Updates/tightens review guidance wording.
src/​parser/​REVIEW.md	Updates parser review guidance to enforce compiler/tree-sitter parity expectations.
src/​parser/​lex2.yy.h	Regenerated lexer header reflecting lexer changes.
src/​parser/​lex.yy.h	Regenerated lexer header reflecting lexer changes.
src/​parser/​ds2_lexer.lpp	Updates/extends lexer rules for expanded escapes (shared CHAR_ESCAPE approach).
src/​parser/​ds_lexer.lpp	Updates/extends lexer rules for expanded escapes (shared CHAR_ESCAPE approach).
src/​ast/​ast_unused.cpp	Fixes side-effect inference by closing over call cycles (union/fixpoint behavior).
src/​ast/​ast_typedecl.cpp	Refines explicit type argument matching to avoid void? stand-in collisions for pointer-like instances.
src/​ast/​ast_simulate.cpp	Adjusts simulation for reinterpret to read operands through eval when needed (cross-slot safety).
src/​ast/​ast_inline.cpp	Fixes inline return/loop-exit interaction for nested-loop constructs.
src/​ast/​ast_infer_type_op.cpp	Clones property base for compound assignment lowering to avoid relocation/crash scenarios.
src/​ast/​ast_infer_type_helper.cpp	Clones with base value for property lowering to preserve stable evaluation semantics.
src/​ast/​ast_const_folding.cpp	Ensures effect flags propagate through field/index/safe-index/swizzle reads and respects mutating indexes.
src/​ast/​ARCHITECTURE_EFFECTS.md	Documents call-cycle closure behavior for side-effect inference.
skills/​daslang/​references/​types.md	Updates language reference content to reflect the new escape set and literal rules.
modules/​dasLiveHost/​live/​live_watch.das	Replaces assert with verify to match new assert restrictions around effectful expressions.
modules/​dasLiveHost/​live/​live_api.das	Replaces assert with verify to match new assert restrictions around effectful expressions.
modules/​dasLiveHost/​live/​live_api_stdio.das	Replaces assert with verify to match new assert restrictions around effectful expressions.
modules/​dasImgui/​tests/​test_grammar_canary.das	Adds grammar canary coverage for expanded escape support.
include/​daScript/​simulate/​simulate_nodes.h	Introduces SimNode_ReinterpretSlot node declaration/definition.
include/​daScript/​simulate/​runtime_string.h	Exposes character escape decoding API/types for shared use.
include/​daScript/​simulate/​ARCHITECTURE.md	Documents reinterpret-slot wrapper rationale and behavior.
include/​daScript/​ast/​ast_serializer.h	Bumps serializer version to account for the explicit-type instance behavior change.
examples/​debugapi/​stack_walker.das	Replaces assert with verify in debug-context checks.
examples/​debugapi/​hw_breakpoint.das	Replaces assert with verify in debug-context checks.
examples/​debugapi/​allocation_tracking.das	Replaces assert with verify in debug-context checks.
doc/​source/​reference/​language/​lexical_structure.rst	Updates reference documentation for expanded escape set and literal behavior.
dastest/​testing_boost.das	Adds shared child_deadline helper and related small testing-utility adjustments.
daslib/​profiler.das	Replaces assert with verify in debug-agent install path.
daslib/​cpp_gen.das	Replaces assert with verify for JSON shape checks per new assert restrictions.
CHANGELIST.md	Adds changelog entries covering the behavior changes and fixes.

_{Review effort: Balanced}

[Copilot]

Note

Copilot was unable to complete this review at the selected tier due to model policy or plan restrictions.

🟡 Changes recommended

The change has critical active issues because both lexer definition files call decodeCharacterEscape without including the header that declares it, which is likely to break compilation of the generated lexers.

2 open issues

• Missing decodeCharacterEscape declaration in ds2_lexer · New
• Missing decodeCharacterEscape declaration in ds_lexer · New

_{Review effort: Balanced}