[ss2165]

Exploratory callback-adapter implementation produced by Codex, left as a draft for a compiler developer to assess and pick up. Preserves borrowed function signatures and inserts adapters where callback calling conventions differ, with separate copyability and droppability checks.

Clearing borrowing flags during specialization broke mutation/write-back in mem_swap and Option.swap. Named and specialized callbacks, nested callbacks, and tracing pass locally with the adapter approach; dynamically captured function adaptation still depends on experimental closure support and is not established as emulator-ready.

Local checks: 2,198 passed, 25 skipped, 13 expected failures; notebook and pytket circuit modules were excluded after process crashes. Ruff and mypy passed. This is an investigation handoff, not a production-ready fix.

Closes #2486

[github-actions]

Bencher Report

Project	guppylang
Branch	codex/fix-generic-borrowed-callbacks-2486
Testbed	Linux

Click to view all benchmark results

Benchmark	hugr_bytes	Benchmark Result bytes x 1e3 (Result Δ%)	Upper Boundary bytes x 1e3 (Limit %)	hugr_nodes	Benchmark Result nodes (Result Δ%)	Upper Boundary nodes (Limit %)
tests/benchmarks/test_big_array.py::test_big_array_compile	📈 view plot 🚷 view threshold	59.84 x 1e3 (0.00%) Baseline: 59.84 x 1e3	60.44 x 1e3 (99.01%)	📈 view plot 🚷 view threshold	4,514.00 (0.00%) Baseline: 4,514.00	4,559.14 (99.01%)
tests/benchmarks/test_ctrl_flow.py::test_many_ctrl_flow_compile	📈 view plot 🚷 view threshold	26.87 x 1e3 (0.00%) Baseline: 26.87 x 1e3	27.14 x 1e3 (99.01%)	📈 view plot 🚷 view threshold	1,182.00 (0.00%) Baseline: 1,182.00	1,193.82 (99.01%)
tests/benchmarks/test_queue_push_pop.py::test_queue_push_benchmark_compile	📈 view plot 🚷 view threshold	6.70 x 1e3 (0.00%) Baseline: 6.70 x 1e3	6.77 x 1e3 (99.01%)	📈 view plot 🚷 view threshold	279.00 (0.00%) Baseline: 279.00	281.79 (99.01%)
tests/benchmarks/test_queue_push_pop.py::test_queue_push_pop_benchmark_compile	📈 view plot 🚷 view threshold	9.22 x 1e3 (0.00%) Baseline: 9.22 x 1e3	9.31 x 1e3 (99.01%)	📈 view plot 🚷 view threshold	371.00 (0.00%) Baseline: 371.00	374.71 (99.01%)

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[codecov-commenter]

Codecov Report

❌ Patch coverage is 85.00000% with 15 lines in your changes missing coverage. Please review.
✅ Project coverage is 93.35%. Comparing base (333d10d) to head (810747e).
⚠️ Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
.../src/guppylang_internals/compiler/expr_compiler.py	81.63%	9 Missing ⚠️
...pylang-internals/src/guppylang_internals/tys/ty.py	73.68%	5 Missing ⚠️
...ls/src/guppylang_internals/checker/expr_checker.py	95.23%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2511      +/-   ##
==========================================
- Coverage   93.36%   93.35%   -0.02%     
==========================================
  Files         167      167              
  Lines       16950    17146     +196     
==========================================
+ Hits        15826    16007     +181     
- Misses       1124     1139      +15     

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[codspeed]

Merging this PR will not alter performance

1 warning

⚠️ 7 benchmarks are dominated by system calls

System calls cannot be simulated consistently and are left out of the measure. The reported value understates the real cost. Switch to the Walltime instrument to measure them.

Learn more about system calls

See affected benchmarks

✅ 11 untouched benchmarks

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_{Comparing codex/fix-generic-borrowed-callbacks-2486 (810747e) with main (7b24318)}