try/catch block does not catch parsing error

[bfamzz]

What is the issue you have?

try/catch block does not catch parsing error

Error message is:
[json.exception.parse_error.101] parse error at line 1, column 1: syntax error while parsing value - invalid literal; last read: 'A'

Please describe the steps to reproduce the issue.

1. Sample code is provided below.

Can you provide a small but working code example?

#include<iostream>
#include <nlohmann/json.hpp>

int main()
{
    try
    {
        nlohmann::json jsonObject = nlohmann::json::parse("Alright");
        std::cout << "Parse completed!\n";
    }
    catch(const std::exception& e)
    {
        std::cerr << e.what() << '\n';
        return -1;
    }
    return 0;
}

What is the expected behavior?

Error should be caught in the try/catch block and program should continue execution.

And what is the actual behavior instead?

Program crashes while in the try block. Parsing error is not caught.

Which compiler and operating system are you using?

• Compiler: GCC 9.3.0 && GCC 10.1.0
• Operating system: Linux - Ubuntu 20.04

Which version of the library did you use?

• [x] latest release version 3.9.1

[nlohmann]

I cannot reproduce this issue: https://godbolt.org/z/d396TE

[nlohmann]

The libraries exceptions do inherit from std::exception. There must be something wrong in your setup I'm afraid.

[bfamzz]

Hi @nlohmann

I cannot reproduce this issue: https://godbolt.org/z/d396TE

Following the link you posted, the error message was displayed.

Kindly see screenshot below.

[nlohmann]

The error message is displayed, because of the line

std::cerr << e.what() << '\n';

And that line is only executed, because the exception has be caught.

[bfamzz]

Thanks @nlohmann You are right. There must be something wrong with my setup. I will close this and investigate my setup further. If I find anything, I'll update this thread with my findings. Thanks for your help.

[xiaozhuai]

@bfamzz @nlohmann
I got the same issue.
On MacOS, it works fine
On android with NDK r15c, it cannot catch the exception, same code

    try {
        throw std::runtime_error("aaaaa");
    } catch (std::exception &e) {
        std::cout << e.what() << "\n"; // works
    }

    try {
        auto aaa = json::parse("{aaaa}");
    } catch (json::exception &e) {
        std::cout << e.what() << "\n"; // not work
    }

[nlohmann]

@xiaozhuai Can you share more information on your setup?