viperproject/carbon

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Verification-condition-generation-based verifier for the Viper intermediate verification language.

Stars: 38
Forks: 24
Open beginner issues: 0
Indexed issues: 151

Dominant language: Scala
License: MPL-2.0
Last GitHub push: Aug 27, 2026
Latest indexed: Sep 20, 2026
Contributing guide: No contributing guide
Code of conduct: No code of conduct
Beginner labels: No beginner labels indexed
PR merge metrics: No merged PRs in 30d

Beginner friendly Everything

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151 open issues indexed

Carbon can prove false Open

Difficulty 4/5 3-5 days Newbie friendliness 48/100

viperproject/carbon#591 · Opened Aug 18, 2026
Conjunction of abstract functions is not able to be asserted Open

Difficulty 4/5 3-5 days Newbie friendliness 52/100

viperproject/carbon#588 · Opened Jul 10, 2026
Wildcard permissions don't work inside predicate bodies Open

Difficulty 4/5 3-5 days Newbie friendliness 38/100

viperproject/carbon#584 · Opened Apr 23, 2026
Carbon does not "frame" trigger-matching heap-dependent functions which depend on QPs (without help) Open

Difficulty 5/5 Over a week Newbie friendliness 35/100

viperproject/carbon#583 · 1 comment · Opened Apr 17, 2026
Incorrect encoding when predicate arguments in fold contain permission introspection Open

bug

viperproject/carbon#577 · 1 assignee · Opened Oct 2, 2025
Heap location is added to the known-folded permission mask in fold statements even if the permission amount is zero Open

bug

viperproject/carbon#576 · 1 comment · 1 assignee · Opened Oct 2, 2025
Known-folded permissions are not updated in unfold statements leading to unsoundness Open

bug

viperproject/carbon#572 · 1 assignee · Opened Jul 31, 2025
Test case sensitive to Z3 seeds Open

Difficulty 3/5 1-2 days Newbie friendliness 38/100

viperproject/carbon#569 · 2 comments · Opened Jun 5, 2025
Incorrect encoding when the predicate argument in an unfold statement contains a permission introspection of the same predicate Open

bug

Difficulty 4/5 3-5 days Newbie friendliness 45/100

viperproject/carbon#568 · 1 comment · Opened Jun 4, 2025
Carbon crashes when packaging wand with wildcard permission on rhs Open

Difficulty 3/5 1-2 days Newbie friendliness 45/100

viperproject/carbon#567 · Opened May 26, 2025
Potential incompleteness with postcondition for mutually recursive functions Open

Difficulty 4/5 3-5 days Newbie friendliness 40/100

viperproject/carbon#564 · Opened Apr 4, 2025
Separating conjunction in package statement does not lead to unreachable state Open

incompleteness magic-wands

Difficulty 4/5 3-5 days Newbie friendliness 28/100

viperproject/carbon#557 · Opened Feb 17, 2025
Stack overflow from Boogie Open

Difficulty 4/5 3-5 days Newbie friendliness 30/100

viperproject/carbon#525 · Opened Aug 30, 2024
Heap-dependent function with QPs generates triggerless axiom Open

Difficulty 5/5 Over a week Newbie friendliness 30/100

viperproject/carbon#522 · 2 comments · Opened Jun 24, 2024
Predicate triggers not working as expected Open

Difficulty 5/5 Over a week Newbie friendliness 25/100

viperproject/carbon#517 · Opened Jun 11, 2024
`applying` not giving permission incompleteness Open

Difficulty 4/5 3-5 days Newbie friendliness 35/100

viperproject/carbon#488 · Opened Jan 16, 2024
Wand package incompleteness? Open

Difficulty 4/5 3-5 days Newbie friendliness 35/100

viperproject/carbon#470 · Opened Oct 16, 2023
Sensitive Behavior with Implications and Triggers Open

Difficulty 5/5 Over a week Newbie friendliness 25/100

viperproject/carbon#464 · 2 comments · Opened Jun 29, 2023
Carbon does not catch predicates that are not well-defined due to multiplication Open

Difficulty 5/5 Over a week Newbie friendliness 32/100

viperproject/carbon#462 · 4 comments · Opened Jun 19, 2023
Incorrect optimization for inhale-exhale expressions Open

Difficulty 4/5 3-5 days Newbie friendliness 35/100

viperproject/carbon#461 · 1 comment · Opened May 31, 2023
Potentially combine well-definedness and exhale code for pure quantifiers. Open

enhancement

Difficulty 5/5 Over a week Newbie friendliness 35/100

viperproject/carbon#458 · Opened May 1, 2023
quantified permissions on the right of a magic wand cause stack trace Open

Difficulty 3/5 1-2 days Newbie friendliness 45/100

viperproject/carbon#449 · Opened Jan 31, 2023
Add full support for quasihavoc statements Open

Difficulty 5/5 Over a week Newbie friendliness 25/100

viperproject/carbon#438 · Opened Nov 11, 2022
Unsoundness of old expressions in magic wands in postconditions Open

Difficulty 5/5 Over a week Newbie friendliness 35/100

viperproject/carbon#437 · 2 comments · Opened Nov 8, 2022
Found an unparsable output from Boogie: Process terminated. Couldn't find a valid ICU package Open

Difficulty 3/5 1-2 days Newbie friendliness 35/100

viperproject/carbon#436 · Opened Oct 24, 2022
Order of well-definedness checks unexpected Open

Difficulty 4/5 3-5 days Newbie friendliness 35/100

viperproject/carbon#435 · 1 comment · Opened Oct 4, 2022
magic wand with quantified resources on RHS causes crash Open

bug

Difficulty 4/5 3-5 days Newbie friendliness 35/100

viperproject/carbon#428 · Opened Jul 8, 2022
Carbon crash Open

Difficulty 3/5 1-2 days Newbie friendliness 42/100

viperproject/carbon#421 · Opened Jun 21, 2022
Inhaling a quantified self framing assertions gives insufficient permission error Open

quantified permissions triggers

Difficulty 4/5 3-5 days Newbie friendliness 35/100

viperproject/carbon#417 · Opened Jun 9, 2022
Wand Packaging Fails when a field is used alongside a function that requires it Open

bug magic-wands

Difficulty 4/5 3-5 days Newbie friendliness 38/100

viperproject/carbon#416 · Opened Jun 8, 2022
Knownfolded permissions unexpectedly recorded even though unfolding is not executed Open

Difficulty 4/5 3-5 days Newbie friendliness 42/100

viperproject/carbon#408 · 1 comment · Opened Mar 17, 2022
Carbon does not report an error when inhaling a not-well-formed postcondition (from a method call) Open

Difficulty 4/5 3-5 days Newbie friendliness 35/100

viperproject/carbon#404 · Opened Feb 9, 2022
Two methods (with sequences and quantified permissions) are verified on their own, but Carbon does not terminate when verifying both Open

Difficulty 5/5 Over a week Newbie friendliness 25/100

viperproject/carbon#403 · Opened Feb 9, 2022
Unsound package algorithm for magic wands Open

bug critical magic-wands

Difficulty 5/5 Over a week Newbie friendliness 30/100

viperproject/carbon#394 · Opened Jul 28, 2021
Unexpected behaviour difference function application vs. asserting precondition Open

Difficulty 4/5 3-5 days Newbie friendliness 30/100

viperproject/carbon#393 · Opened Jul 21, 2021
Potentially incorrect handling of goto Open

Difficulty 5/5 Over a week Newbie friendliness 25/100

viperproject/carbon#390 · Opened Jun 30, 2021
Carbon doesn't take not-wellformed method precondition into account Open

Difficulty 4/5 3-5 days Newbie friendliness 35/100

viperproject/carbon#388 · 1 comment · Opened Jun 2, 2021
Magic wands used in predicate bodies or function preconditions cause a crash (current VSCode version) Open

Difficulty 5/5 Over a week Newbie friendliness 25/100

viperproject/carbon#379 · Opened Apr 7, 2021
Verifcation of "passing on" permissions fails Open

Difficulty 4/5 3-5 days Newbie friendliness 28/100

viperproject/carbon#377 · 4 comments · Opened Mar 22, 2021
Counterexample extraction fails due to Boogie Open

counterexamples

Difficulty 4/5 3-5 days Newbie friendliness 35/100

viperproject/carbon#367 · Opened Nov 25, 2020
Renaming a field appears to suppress a expected error message (injective QP receivers) Open

Difficulty 4/5 3-5 days Newbie friendliness 35/100

viperproject/carbon#361 · 2 comments · Opened Jul 31, 2020
Postcondition holds using silicon but not carbon Open

Difficulty 4/5 3-5 days Newbie friendliness 35/100

viperproject/carbon#359 · Opened Jun 11, 2020
Quantifiers break lockstep unfolding of recursive functions and predicates Open

Difficulty 5/5 Over a week Newbie friendliness 20/100

viperproject/carbon#356 · Opened Jun 1, 2020
Outputs differ between Silicon and Carbon — Incompleteness? Open

Difficulty 4/5 3-5 days Newbie friendliness 30/100

viperproject/carbon#354 · Opened Apr 4, 2020
"Packaging wand might fail" in Viper online example Open

magic-wands

Difficulty 4/5 3-5 days Newbie friendliness 35/100

viperproject/carbon#351 · 1 comment · Opened Mar 10, 2020
Handling unfoldings properly when asserting/exhaling Open

bug major unfolding

Difficulty 5/5 Over a week Newbie friendliness 25/100

viperproject/carbon#348 · 2 comments · Opened Feb 26, 2020
Make sequence axiomatisation common with Silicon Open

enhancement minor

Difficulty 5/5 Over a week Newbie friendliness 20/100

viperproject/carbon#295 · 2 comments · Opened Feb 3, 2020
Missing a case for inhaling (quantified wand with predicates on both sides) Open

bug magic-wands major

Difficulty 3/5 1-2 days Newbie friendliness 45/100

viperproject/carbon#294 · Opened Jan 2, 2020
Sequence-related test case doesn't terminate Open

bug major performance

Difficulty 4/5 3-5 days Newbie friendliness 35/100

viperproject/carbon#293 · Opened Jan 1, 2020
Missing axiom(s) in the axiomatization of sets Open

bug major

Difficulty 4/5 3-5 days Newbie friendliness 35/100

viperproject/carbon#292 · Opened Dec 13, 2019

viperproject/carbon

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