Since SnarkJS needs to support all versions of circom, and this project doesn't follow semantic versioning, it would be helpful to include all digits in the version number returned by the getVersion export.

This would allow us to do feature switching based on the version of the compiler.

In https://github.com/iden3/circom/commit/b953bf92df54004373a4049e29f0e160a5a57486, @miguelis made circom forcibly exit on success, which makes many workflows (such as using the circom tool inside a script or when using it in WASM) break. It would probably be fine to forcibly exit with a code if there is an error but never should you forcibly exit with 0 on a success.

I tried removing the exit and circom hits an unreachable in the code, so more fixes will need to be applied to make the code work correctly.

Fixes https://github.com/iden3/circom/issues/82

This PR adds log("foo", 1) syntax to the circom language. The label is then printed when generating a witness with the C++ witness generator. It is very hard to add these labels to the wasm generator, so the label is discarded and only the value is printed when generating with the witness in wasm.

This feature is a huge quality-of-life improvement for large circuit authors, like @yi-sun and other @0xPARC members.

For circuits larger than ~1M constraints, it would be helpful if the witness generation exited with error when it detects a proof that is too large for wasm, and suggests compiling in C++ instead.

Hello everyone~ 😀

Recently, I'm writing circom version of my python functions. (To make the zk proof of python functions' output)

If I have a python function, I can easily pass the array into and retrieve the array from that function.

def myFunc(in_array):
    # Some calculations
    return out_array

if __name__ == "__main__":
    in_array = [1, 2, 3];
    out_array = myFunc(in_array);

However, according to docs, I cannot find examples or somewhere else that talking about passing array into a function. Currently, I guess that it might be something like this:

function myFunc(in_array) {
    // Some calculations
    return out_array;
}

template mainFunc() {
	signal private input in_array; // A fixed length array
	signal private input b;
	signal output out;
	
	var out_array = myFunc(in_array);
}

component main = mainFunc();

Thanks for anyone willing to give me the answer or some clues about how I could develop in this situation. 🙏❤

Hello, I have the following minimal circuit that uses a hexadecimal number as an input from a json file:

pragma circom 2.0.0;

template POC() {
    signal input a;
    signal input b;
    signal input c;

    log(a);
    log(b);
    log(c);
}

component main = POC();

Using the following json as an input file:

{"a": "0x42", "b": 100, "c": "110"}

The circuit logs the following:

0
100
110

I am fairly certain hexadecimal numbers worked as an input in previous versions of circom. Is this functionality still supported, or is this now the intended behavior?

circom2 circuits/c.circom --r1cs --wasm --sym --c does not spit out a wasm file. The best error message I could find is previous errors were found. Is this part working at all?

According to https://twitter.com/railgun_project/status/1500966895733850117 they've also had problems that they had to put out a bounty for it.

Also I don't have the best experience working with circom2, a lot of documentation's outdated, makes me sad:(

I was trying to follow the example from the official documentation https://docs.circom.io/getting-started/computing-the-witness/#computing-the-witness-with-c. I was able to compile the C++ witness calculator on Mac OS thanks to https://github.com/iden3/circom/pull/12. However, when I tried to generate the witness I got an error:

zsh: illegal hardware instruction  ./circuit input.json witness.wtns

The code to reproduce the issue is in the repo: https://github.com/alxkzmn/factor/commit/5690ffc08a52c27f304966cb529bdbeab90c0daf

Steps to reproduce:

cd circuit_cpp
make
./circuit input.json witness.wtns

Hello !

I'm trying to verify a commitment of a rescue function. The problem is when I write the commit in the inputs, it's directly modified by the circuit without reasons (the value is less than bn128's elliptic curve group order). Here is my simple circuit :

pragma circom 2.0.0;

include "./rescue.circom";

template test(){ signal input in; signal input commit; signal output out;

component hash = rescue(1);

hash.entree[0] <== in;

out <== hash.sortie;

}

component main {public [commit]} = test();

This is what the public file and the input files looks like : input : 15522569492626651840248353495983403506074603540762064124302882378518279710261 (commit) public : 15522569492626651840248353495983403506074603540762064124302882378518279710261 (hash result) and 15522569492626650996385962682425768945933593965259583670031600469260676104192 (wrong copy of my input)

Can someone tell me if it's an error from me or not?

Thomas

It can be temporally fixed by compling, keeping the arm64 code from the libwabt.a fat binary and compile again

# for commit a9a4a24e4e95debb0230a233c259fac7d3e1e186
cargo build --release
lipo target/release/build/wabt-sys-ccf4f394b6bb7490/out/build/libwabt.a -thin arm64 -output target/release/build/wabt-sys-ccf4f394b6bb7490/out/build/libwabt.a
cargo build --release

Hey!

I have written a zk-circuit that works perfectly fine when all input signals are set to default/private. However, if I want to change the visibility of 1-2 signals to public the zkey generation takes around 10 min (instead of the previous 30s). component main {public [a,b]}= SomeCircuit();

Further, I can no longer generate ZK proofs with help of the snarkjs implementation. Currently I use the following command: const { proof, publicSignals } = await snarkjs.plonk.fullProve(inputs, "circuit.wasm", "circuit_final.zkey");

As said, with all signals set to private it works perfectly fine, if I set some to public I get the following error: "Uncaught (in promise) TypeError: Failed to fetch"

Since I use circom and snarkjs as part of my master thesis I would appreciate any fast answer :)

Edit: My circuit has around 75k constraints and I use powersOfTau28_hez_final_18.ptau for the zkey generation.

Edit2: An update from circom 2.0.7 to 2.1.2 and from snarkjs 0.4.24 to 0.5.0 did NOT fix the issue.

Best Regards, Crashpilot

There was error while doing make command in generated cpp directory. Error example:

g++ -c fr.cpp -std=c++11 -O3 -I.
In file included from fr.cpp:1:
./fr.hpp:71:50: error: unknown type name 'uint'; did you mean 'int'?
void Fr_str2element(PFrElement pE, char const*s, uint base);
                                                 ^~~~
                                                 int
fr.cpp:56:51: error: unknown type name 'uint'; did you mean 'int'?
void Fr_str2element(PFrElement pE, char const *s, uint base) {
                                                  ^~~~
                                                  int

matElemMul.circom:

pragma circom 2.0.0;

// matrix multiplication by element
template matElemMul (m,n) {
    signal input a[m][n];
    signal input b[m][n];
    signal output out[m][n];
    
    for (var i=0; i < m; i++) {
        for (var j=0; j < n; j++) {
            out[i][j] <== a[i][j] * b[i][j];
        }
    }
}
component main = matElemMul(4,4);

I use the --c option to compile, but when I compute the witness in cpp, I prompt "illegal instruction". So how to use it correctly?

env:

ubuntu 18.04
gcc 6.5.0 

Motivation

We are using snarkjs as backend for circom.

     const { proof, publicSignals } = await snarkjs.groth16.fullProve(
            inputs,
            circuitWasmPath,
            zkeyPath
     )

Variable inputs have type any. Every time we changed circom file we need to update inputs structs. However any make us hard to remember and easy to create error/bugs. I think we should create function for auto gen inputs/outputs interface of circom. It's help developer easy to test and use circom.

Proposal

Create new interface command line to generate inputs/outputs interface.

Example

circom merkle_tree.circom --types types.ts

Circom file

include "../../../node_modules/circomlib/circuits/comparators.circom";

template Example() {
    signal input first_input;
    signal input second_input[100];
    signal output first_output;
}

We will generate inputs interface like bellow:

interface ExampleInput {
    first_input: bigint;
    second_input: bigint[];
}

Samething for outputs interface.

Thank Iden3 for awesome work!

A lot of logging in circuits is primarily used for generating "stack traces" of the execution when generating a witness. Ideally, circom should have a "trace" mode that injects log statements for:

1. entering template
2. all template inputs
3. all template outputs
4. exiting templates

These would then be logged (or traced some other way?) recursively as the witness is generated.

When developing a circuit, an author will likely include many log statements. It would be ideal to have a compilation mode that removes all of these log statements from the output when compiling for production.