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Repeated occurrences of one lifetime parameter receive different actual regions · case 01

Repeated occurrences of one lifetime parameter receive different actual regions.

Verified by executionVariant 1 · 21 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The static analyzer mishandles repeated substitution: repeated occurrences of one lifetime parameter receive different actual regions.

THE FAILURE

The static analyzer mishandles repeated substitution: repeated occurrences of one lifetime parameter receive different actual regions.

Unsuccessful approach: The partial repair uses if any(len(set(xs))>2 for xs in d['occurrences'].values()): errors.append('repeated-substitution'), which still violates the stipulated analysis contract.

Case contract

Check generic borrow-summary instantiation. Generic lifetime arguments match parameter arity; parameter substitution is positional; repeated occurrences substitute consistently; recursive instantiation uses each callee actual mapping; static lifetime is not substituted; inferred anonymous lifetimes are fresh per call; where-outlives obligations instantiated in declared direction; associated lifetime applications include all type arguments; recursive summary fixed point cannot be accepted while new obligations remain; monomorphized reference types retain lifetime proof metadata. Input is a fully explicit descriptor of the stated toy IR. Return rule identifiers in declaration order; absent optional obligations use the provided neutral defaults. No rule is an assertion about a production language.

Why this case matters

A finite offline static-analysis model of ownership and borrowing; it does not execute the analyzed program.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(d):
    errors=[]
    if len(d['params'])!=len(d['args']): errors.append('lifetime-arity')
    if d['expected_mapping']!=d['actual_mapping']: errors.append('positional-substitution')
    if False: errors.append('repeated-substitution')
    if d['recursive_expected']!=d['recursive_actual']: errors.append('recursive-actual-map')
    if d['static_before']!=d['static_after']: errors.append('static-preservation')
    if len(d['anonymous_calls'])==len(d['anonymous_ids']) and len(set(d['anonymous_ids']))!=len(d['anonymous_ids']): errors.append('anonymous-freshness')
    if set(map(tuple,d['expected_outlives']))!=set(map(tuple,d['actual_outlives'])): errors.append('where-direction')
    if d['associated_args']!=d['recorded_args']: errors.append('associated-arguments')
    if d['accepted'] and bool(d['pending']): errors.append('summary-fixed-point')
    if not set(d['reference_types'])<=set(d['proof_metadata']): errors.append('erased-proof-metadata')
    return errors
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
base={'params': [], 'args': [], 'expected_mapping': {}, 'actual_mapping': {}, 'occurrences': {}, 'recursive_expected': {}, 'recursive_actual': {}, 'static_before': None, 'static_after': None, 'anonymous_calls': [], 'anonymous_ids': [], 'expected_outlives': [], 'actual_outlives': [], 'associated_args': [], 'recorded_args': [], 'pending': [], 'accepted': False, 'reference_types': [], 'proof_metadata': []}
check('well formed empty obligations',solve(base),[])
check('lifetime-arity regression 0', solve(dict(base, **({'params':['a'],'args':['x','y']}))), ['lifetime-arity'])
check('lifetime-arity regression 1', solve(dict(base, **({'params':[N],'args':[N,N+1]}))), ['lifetime-arity'])
check('positional-substitution regression 0', solve(dict(base, **({'expected_mapping':{'a':'x','b':'y'},'actual_mapping':{'a':'y','b':'x'}}))), ['positional-substitution'])
check('positional-substitution regression 1', solve(dict(base, **({'expected_mapping':{'a':N,'b':N+1},'actual_mapping':{'a':N+1,'b':N}}))), ['positional-substitution'])
check('repeated-substitution regression 0', solve(dict(base, **({'occurrences':{'a':['x','y']}}))), ['repeated-substitution'])
check('repeated-substitution regression 1', solve(dict(base, **({'occurrences':{'a':[N,N+1]}}))), ['repeated-substitution'])
check('recursive-actual-map regression 0', solve(dict(base, **({'recursive_expected':{'call':'b'},'recursive_actual':{'call':'a'}}))), ['recursive-actual-map'])
check('recursive-actual-map regression 1', solve(dict(base, **({'recursive_expected':{'call':N+1},'recursive_actual':{'call':N}}))), ['recursive-actual-map'])
check('static-preservation regression 0', solve(dict(base, **({'static_before':'static','static_after':'a'}))), ['static-preservation'])
check('static-preservation regression 1', solve(dict(base, **({'static_before':'static','static_after':N}))), ['static-preservation'])
check('anonymous-freshness regression 0', solve(dict(base, **({'anonymous_calls':['c1','c2'],'anonymous_ids':['r','r']}))), ['anonymous-freshness'])
check('anonymous-freshness regression 1', solve(dict(base, **({'anonymous_calls':[N,N+1],'anonymous_ids':[0,0]}))), ['anonymous-freshness'])
check('where-direction regression 0', solve(dict(base, **({'expected_outlives':[('a','b')],'actual_outlives':[('b','a')]}))), ['where-direction'])
check('where-direction regression 1', solve(dict(base, **({'expected_outlives':[(N,N+1)],'actual_outlives':[(N+1,N)]}))), ['where-direction'])
check('associated-arguments regression 0', solve(dict(base, **({'associated_args':['a','b'],'recorded_args':['b','a']}))), ['associated-arguments'])
check('associated-arguments regression 1', solve(dict(base, **({'associated_args':[N,N+1],'recorded_args':[N+1,N]}))), ['associated-arguments'])
check('summary-fixed-point regression 0', solve(dict(base, **({'accepted':True,'pending':['a']}))), ['summary-fixed-point'])
check('summary-fixed-point regression 1', solve(dict(base, **({'accepted':True,'pending':[N]}))), ['summary-fixed-point'])
check('erased-proof-metadata regression 0', solve(dict(base, **({'reference_types':['a','b'],'proof_metadata':['a']}))), ['erased-proof-metadata'])
check('erased-proof-metadata regression 1', solve(dict(base, **({'reference_types':[N,N+1],'proof_metadata':[N]}))), ['erased-proof-metadata'])
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
well formed empty obligations[][]Passed
lifetime-arity regression 0['lifetime-arity']['lifetime-arity']Passed
lifetime-arity regression 1['lifetime-arity']['lifetime-arity']Passed
positional-substitution regression 0['positional-substitution']['positional-substitution']Passed
positional-substitution regression 1['positional-substitution']['positional-substitution']Passed
repeated-substitution regression 0[]['repeated-substitution']Failed
repeated-substitution regression 1[]['repeated-substitution']Failed
recursive-actual-map regression 0['recursive-actual-map']['recursive-actual-map']Passed
recursive-actual-map regression 1['recursive-actual-map']['recursive-actual-map']Passed
static-preservation regression 0['static-preservation']['static-preservation']Passed
static-preservation regression 1['static-preservation']['static-preservation']Passed
anonymous-freshness regression 0['anonymous-freshness']['anonymous-freshness']Passed
anonymous-freshness regression 1['anonymous-freshness']['anonymous-freshness']Passed
where-direction regression 0['where-direction']['where-direction']Passed
where-direction regression 1['where-direction']['where-direction']Passed
associated-arguments regression 0['associated-arguments']['associated-arguments']Passed
associated-arguments regression 1['associated-arguments']['associated-arguments']Passed
summary-fixed-point regression 0['summary-fixed-point']['summary-fixed-point']Passed
summary-fixed-point regression 1['summary-fixed-point']['summary-fixed-point']Passed
erased-proof-metadata regression 0['erased-proof-metadata']['erased-proof-metadata']Passed
erased-proof-metadata regression 1['erased-proof-metadata']['erased-proof-metadata']Passed

SHA-256 / 49559d325ee61b54f3de6558d29d01e2c1639450a5b9a4073c05e2d54878fff1

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(d):
    errors=[]
    if len(d['params'])!=len(d['args']): errors.append('lifetime-arity')
    if d['expected_mapping']!=d['actual_mapping']: errors.append('positional-substitution')
    if any(len(set(xs))>2 for xs in d['occurrences'].values()): errors.append('repeated-substitution')
    if d['recursive_expected']!=d['recursive_actual']: errors.append('recursive-actual-map')
    if d['static_before']!=d['static_after']: errors.append('static-preservation')
    if len(d['anonymous_calls'])==len(d['anonymous_ids']) and len(set(d['anonymous_ids']))!=len(d['anonymous_ids']): errors.append('anonymous-freshness')
    if set(map(tuple,d['expected_outlives']))!=set(map(tuple,d['actual_outlives'])): errors.append('where-direction')
    if d['associated_args']!=d['recorded_args']: errors.append('associated-arguments')
    if d['accepted'] and bool(d['pending']): errors.append('summary-fixed-point')
    if not set(d['reference_types'])<=set(d['proof_metadata']): errors.append('erased-proof-metadata')
    return errors
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
base={'params': [], 'args': [], 'expected_mapping': {}, 'actual_mapping': {}, 'occurrences': {}, 'recursive_expected': {}, 'recursive_actual': {}, 'static_before': None, 'static_after': None, 'anonymous_calls': [], 'anonymous_ids': [], 'expected_outlives': [], 'actual_outlives': [], 'associated_args': [], 'recorded_args': [], 'pending': [], 'accepted': False, 'reference_types': [], 'proof_metadata': []}
check('well formed empty obligations',solve(base),[])
check('lifetime-arity regression 0', solve(dict(base, **({'params':['a'],'args':['x','y']}))), ['lifetime-arity'])
check('lifetime-arity regression 1', solve(dict(base, **({'params':[N],'args':[N,N+1]}))), ['lifetime-arity'])
check('positional-substitution regression 0', solve(dict(base, **({'expected_mapping':{'a':'x','b':'y'},'actual_mapping':{'a':'y','b':'x'}}))), ['positional-substitution'])
check('positional-substitution regression 1', solve(dict(base, **({'expected_mapping':{'a':N,'b':N+1},'actual_mapping':{'a':N+1,'b':N}}))), ['positional-substitution'])
check('repeated-substitution regression 0', solve(dict(base, **({'occurrences':{'a':['x','y']}}))), ['repeated-substitution'])
check('repeated-substitution regression 1', solve(dict(base, **({'occurrences':{'a':[N,N+1]}}))), ['repeated-substitution'])
check('recursive-actual-map regression 0', solve(dict(base, **({'recursive_expected':{'call':'b'},'recursive_actual':{'call':'a'}}))), ['recursive-actual-map'])
check('recursive-actual-map regression 1', solve(dict(base, **({'recursive_expected':{'call':N+1},'recursive_actual':{'call':N}}))), ['recursive-actual-map'])
check('static-preservation regression 0', solve(dict(base, **({'static_before':'static','static_after':'a'}))), ['static-preservation'])
check('static-preservation regression 1', solve(dict(base, **({'static_before':'static','static_after':N}))), ['static-preservation'])
check('anonymous-freshness regression 0', solve(dict(base, **({'anonymous_calls':['c1','c2'],'anonymous_ids':['r','r']}))), ['anonymous-freshness'])
check('anonymous-freshness regression 1', solve(dict(base, **({'anonymous_calls':[N,N+1],'anonymous_ids':[0,0]}))), ['anonymous-freshness'])
check('where-direction regression 0', solve(dict(base, **({'expected_outlives':[('a','b')],'actual_outlives':[('b','a')]}))), ['where-direction'])
check('where-direction regression 1', solve(dict(base, **({'expected_outlives':[(N,N+1)],'actual_outlives':[(N+1,N)]}))), ['where-direction'])
check('associated-arguments regression 0', solve(dict(base, **({'associated_args':['a','b'],'recorded_args':['b','a']}))), ['associated-arguments'])
check('associated-arguments regression 1', solve(dict(base, **({'associated_args':[N,N+1],'recorded_args':[N+1,N]}))), ['associated-arguments'])
check('summary-fixed-point regression 0', solve(dict(base, **({'accepted':True,'pending':['a']}))), ['summary-fixed-point'])
check('summary-fixed-point regression 1', solve(dict(base, **({'accepted':True,'pending':[N]}))), ['summary-fixed-point'])
check('erased-proof-metadata regression 0', solve(dict(base, **({'reference_types':['a','b'],'proof_metadata':['a']}))), ['erased-proof-metadata'])
check('erased-proof-metadata regression 1', solve(dict(base, **({'reference_types':[N,N+1],'proof_metadata':[N]}))), ['erased-proof-metadata'])
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
well formed empty obligations[][]Passed
lifetime-arity regression 0['lifetime-arity']['lifetime-arity']Passed
lifetime-arity regression 1['lifetime-arity']['lifetime-arity']Passed
positional-substitution regression 0['positional-substitution']['positional-substitution']Passed
positional-substitution regression 1['positional-substitution']['positional-substitution']Passed
repeated-substitution regression 0[]['repeated-substitution']Failed
repeated-substitution regression 1[]['repeated-substitution']Failed
recursive-actual-map regression 0['recursive-actual-map']['recursive-actual-map']Passed
recursive-actual-map regression 1['recursive-actual-map']['recursive-actual-map']Passed
static-preservation regression 0['static-preservation']['static-preservation']Passed
static-preservation regression 1['static-preservation']['static-preservation']Passed
anonymous-freshness regression 0['anonymous-freshness']['anonymous-freshness']Passed
anonymous-freshness regression 1['anonymous-freshness']['anonymous-freshness']Passed
where-direction regression 0['where-direction']['where-direction']Passed
where-direction regression 1['where-direction']['where-direction']Passed
associated-arguments regression 0['associated-arguments']['associated-arguments']Passed
associated-arguments regression 1['associated-arguments']['associated-arguments']Passed
summary-fixed-point regression 0['summary-fixed-point']['summary-fixed-point']Passed
summary-fixed-point regression 1['summary-fixed-point']['summary-fixed-point']Passed
erased-proof-metadata regression 0['erased-proof-metadata']['erased-proof-metadata']Passed
erased-proof-metadata regression 1['erased-proof-metadata']['erased-proof-metadata']Passed

SHA-256 / b51a0431d0804f15566486afa71633996301f6d6a05d89cfbc6dd39067212637

HELD IN THE MEMBER ARCHIVE

The verified repair and its recorded checks are member-only.

This mechanism has 21 recorded checks per implementation. The open-access tier publishes the failure and the unsuccessful fix; the repaired source that passes every check, and the observations that prove it, are available to members.

Every case sharing this mechanism uses the same contract and the same repair, so this one record is held back for all of them.

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Verification & scope

The explicitly stated toy language is the complete scope; this is not a production compiler or a claim about Rust semantics. This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.

Observations recorded using Python 3.12.14 at 2026-09-29T14:44:10.295010+00:00.

Case digest / 988c41de9970d889d08dfa2bc27ef4f929ff208941d0640743049af1bef7c093