Circom Circuits

Troubleshooting Sindri errors with Circom circuits.

When using Sindri to create and prove Circom circuits, you may encounter an error response from your request. The following list shows common errors at each API endpoint.

Circuit Detail

Error	Exception caused by invalid access: trying to access to a signal that is not initialized
Status Code	200
Circuit Status	Failed
Cause	Syntax Error or Code Error
Resolution	Your code has a syntax or logic issue and needs to be fixed. In this example, the signal xs[0] is not initialized and circuit compilation fails.

Example Response Body "error"

{
  "error": "cmd: circom2 --output /tmp/circuits/9a2e698c-eee5-4735-8d9c-54b6d1d7a35f_1689289553776689 --c /tmp/circuits/9a2e698c-eee5-4735-8d9c-54b6d1d7a35f_1689289553776689/code/main_code.circom stdout:  stderr: error[T3001]: Exception caused by invalid access: trying to access to a signal that is not initialized\n   ┌─ '/tmp/circuits/9a2e698c-eee5-4735-8d9c-54b6d1d7a35f_1689289553776689/code/main_code.circom':10:5\n   │\n10 │     xs[0] === X;\n   │     ^^^^^ found here\n   │\n   = call trace:\n     ->Cubic\n\nprevious errors were found\n"
}

Error	The file ../circomlib/mimc.circom to be included has not been found
Status Code	200
Circuit Status	Failed
Cause	File specified to be included was not found. In the error message above, ../circomlib/mimc.circom would be replaced by the name of your missing file.
Resolution	Include the required file with your upload and check that the import path is up to date. Circomlib files commonly cross reference one another; you may need to include multiple templates from Circomlib for one template used in your main circuit definition.

Example Response Body "error"

{
  "error": "cmd: circom2 --output /tmp/circuits/621587eb-396f-4ea0-89cf-5ed4f2c7f0c5_1689295274588843 --c /tmp/circuits/621587eb-396f-4ea0-89cf-5ed4f2c7f0c5_1689295274588843/code/main_code.circom stdout:  stderr: error[P1014]:  The file ../circomlib/mimc.circom to be included has not been found\n = Consider using compilation option -l to indicate include paths\n\nprevious errors were found\n"
}

Error	'circuit.circom' file is missing
Status Code	200
Circuit Status	Failed
Cause	circuit.circom file is not present in the compressed upload.
Resolution	Ensure that your primary circuit definition file is called circuit.circom and include it in the code directory.

Example Response Body "error"

{
  "error": "'circuit.circom' file is missing."
}

Proof Detail

Error	Invalid number in JSON input: -1
Status Code	200
Proof Status	Failed
Cause	User compiles via c++ but has json input with a negative integer encoded as a string.
Resolution	While the NodeJS WASM witness generator will accept JSON values of the form "-1", the C++ witness generator will not. Any fields likely to have negative integer values need to be encoded as integers, not strings.

Example Response Body "error"

{
  "error": "cmd: /tmp/proofs/664b4eb0-627c-4c73-b0db-8f0eed2c1f0b_1689295321697735/main_code /tmp/proofs/664b4eb0-627c-4c73-b0db-8f0eed2c1f0b_1689295321697735/input.json /tmp/proofs/664b4eb0-627c-4c73-b0db-8f0eed2c1f0b_1689295321697735/witness.wtns stdout:  stderr: terminate called after throwing an instance of 'std::runtime_error'\n  what():  Invalid number in JSON input: -1\n\nqemu: uncaught target signal 6 (Aborted) - core dumped\n"
}

Field	Value
Error	Circom_CalcWit::getInputSignalHashPosition(u64): Assertion ``false' failed
Status Code	200
Proof Status	Failed
Cause	User is missing a JSON field in their proof input.
Resolution	Include required proof input fields.

Example Response Body "error"

{
  "error": "cmd: /tmp/proofs/0589f1e5-6cd8-46d8-94cb-31995302c13f_1689295365554809/main_code /tmp/proofs/0589f1e5-6cd8-46d8-94cb-31995302c13f_1689295365554809/input.json /tmp/proofs/0589f1e5-6cd8-46d8-94cb-31995302c13f_1689295365554809/witness.wtns stdout:  stderr: Signal not found\nmain_code: calcwit.cpp:60: uint Circom_CalcWit::getInputSignalHashPosition(u64): Assertion `false' failed.\nqemu: uncaught target signal 6 (Aborted) - core dumped\n"
}

Field	Value
Error	Circom_CalcWit::getInputSignalHashPosition(u64): Assertion ``false' failed
Status Code	200
Proof Status	Failed
Cause	User has an extra JSON field in their proof input.
Resolution	Remove extra proof input fields.

Example Response Body "error"

{
  "error": "cmd: /tmp/proofs/05ed3fdb-4682-42b9-b36a-fe40bd19e97d_1689295410432463/main_code /tmp/proofs/05ed3fdb-4682-42b9-b36a-fe40bd19e97d_1689295410432463/input.json /tmp/proofs/05ed3fdb-4682-42b9-b36a-fe40bd19e97d_1689295410432463/witness.wtns stdout:  stderr: Signal not found\nmain_code: calcwit.cpp:60: uint Circom_CalcWit::getInputSignalHashPosition(u64): Assertion `false' failed.\nqemu: uncaught target signal 6 (Aborted) - core dumped\n"
}