Incorrect false for tuple

[lucasccordeiro]

$ ./verify.sh --llm --model openrouter/deepseek/deepseek-chat ~/ESBMC_Project/esbmc/regression/python/tuple1/main.py

Working directory: /tmp/tmp.Ex6Nf63ySb
Running shedskin on main.py...
*** SHED SKIN Python-to-C++ Compiler 0.9.10 ***
Copyright 2005-2024 Mark Dufour and contributors; License GNU GPL version 3 (See LICENSE)

processing [#################################] 100%

[prebuild time: 0.32 secs]

Converting C++ to C using aider...
Attempt 1 of 5 to generate valid code...
─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
Creating empty file /tmp/tmp.Ex6Nf63ySb/main.c
Aider v0.74.3.dev19+g44b1acd3
Model: openrouter/deepseek/deepseek-chat with diff edit format
Git repo: none
Repo-map: disabled
Added main.c to the chat.
Added main.cpp to the chat (read-only).

I'll convert the C++ code to C while maintaining the same functionality and verification properties. Here's the conversion:

main.c

<<<<<<< SEARCH

#include <stdio.h>
#include <stdlib.h>
#include <assert.h>

#define False 0
#define True 1

typedef struct {
int elements[3];
int size;
} tuple_t;

void tuple_init(tuple_t *t, int size, int e1, int e2, int e3) {
t->size = size;
t->elements[0] = e1;
t->elements[1] = e2;
t->elements[2] = e3;
}

void tuple_setitem(tuple_t *t, int index, int value) {
// Simulate Python's tuple immutability
// This should fail since tuples are immutable
assert(False && "Tuple should be immutable!");
}

int main() {
tuple_t t;
tuple_init(&t, 3, 1, 2, 3);

 // Try to modify the tuple - this should trigger the assertion
 tuple_setitem(&t, 0, 100);

 return 0;

}

REPLACE

Key changes made:

1 Replaced C++ classes with C structs
2 Removed namespaces and C++ specific features
3 Used fixed-size arrays instead of dynamic allocation
4 Maintained the tuple immutability check through an assertion
5 Kept the same logical error (trying to modify an immutable tuple)
6 Added necessary C headers
7 Simplified the code while maintaining the verification properties

The code will fail verification when ESBMC tries to verify it, as it should, because it attempts to modify an immutable tuple. This maintains the original
verification property from the C++ code.

To verify with ESBMC, you can run:

esbmc main.c --incremental-bmc

Tokens: 3.0k sent, 405 received. Cost: $0.00053 message, $0.00053 session.
Applied edit to main.c

esbmc main.c --incremental-bmc
Successfully generated valid code on attempt 1
Successfully converted C++ to C
Checking for threading...
No threading detected

ESBMC command to be executed:
esbmc --segfault-handler -I/usr/include -I/usr/local/include -I. -I/usr/lib/gcc/x86_64-linux-gnu/11/include main.c --incremental-bmc --no-pointer-check --no-align-check --add-symex-value-sets --compact-trace

Running ESBMC...
ESBMC version 7.8.1 64-bit x86_64 linux
Target: 64-bit little-endian x86_64-unknown-linux with esbmclibc
Parsing main.c
Converting
Generating GOTO Program
GOTO program creation time: 0.175s
GOTO program processing time: 0.008s
Checking base case, k = 1
Starting Bounded Model Checking
Symex completed in: 0.002s (25 assignments)
Slicing time: 0.000s (removed 1 assignments)
Generated 1 VCC(s), 1 remaining after simplification (24 assignments)
No solver specified; defaulting to Boolector
Encoding remaining VCC(s) using bit-vector/floating-point arithmetic
Encoding to solver time: 0.003s
Solving with solver Boolector 3.2.2
Runtime decision procedure: 0.084s
Building error trace

[Counterexample]

State 1 file /home/lucas/ESBMC_Project/esbmc/src/c2goto/library/stdlib.c line 229 column 1 thread 0

ATOI_MAP = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }

State 2 file main.c line 27 column 5 function main thread 0

t = { .elements = { 0 } }

State 3 file main.c line 14 column 5 function tuple_init thread 0

t->size = 3 (00000000 00000000 00000000 00000011)

State 4 file main.c line 15 column 5 function tuple_init thread 0

t->elements[0] = 1 (00000000 00000000 00000000 00000001)

State 5 file main.c line 16 column 5 function tuple_init thread 0

t->elements[1] = 2 (00000000 00000000 00000000 00000010)

State 6 file main.c line 17 column 5 function tuple_init thread 0

t->elements[2] = 3 (00000000 00000000 00000000 00000011)

State 7 file main.c line 23 column 5 function tuple_setitem thread 0

Violated property:
file main.c line 23 column 5 function tuple_setitem
assertion False && "Tuple should be immutable!"
0 && (_Bool)(&"Tuple should be immutable!"[0])

VERIFICATION FAILED

Bug found (k = 1)
Temporary files available in: /tmp/tmp.Ex6Nf63ySb