Assert when using std::views::filter and GCC 10

[gwjo]

Description

After upgrading from 3.9.1 to 3.11.3 the code asserts when iterating over a json array that's been filtered using std::views::filter due to an uninitialized iterator.

In addition to my failure with 3.11.3 and GCC 10.2, I checked other combinations on Godbolt and observed the following (❌ represents the assert is seen)

	GCC 10.2	GCC 10.5	GCC 11.1	GCC trunk	Clang 16
3.9.1	✅	✅	✅	✅	✅
3.10.5	✅	✅	✅	✅	✅
3.11.1	❌	❌	❌	✅	✅
trunk	❌	❌	❌	✅	✅

Reproduction steps

https://godbolt.org/z/WbexYTqnf

Expected vs. actual results

std::views::filter should allow you to filter a json array.

Minimal code example

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

using nlohmann::json;

int main()
{
    auto noOpFilter = std::views::filter([](auto&&){ return true; });
    json j = {1, 2, 3};
    auto filtered = j | noOpFilter;
    std::cout << *filtered.begin() << std::endl;
    return 0;
}

Error messages

output.s: /opt/compiler-explorer/libs/nlohmann_json/trunk/single_include/nlohmann/json.hpp:13346: bool nlohmann::json_abi_v3_11_3::detail::iter_impl<BasicJsonType>::operator==(const IterImpl&) const [with IterImpl = nlohmann::json_abi_v3_11_3::detail::iter_impl<nlohmann::json_abi_v3_11_3::basic_json<> >; typename std::enable_if<(std::is_same<IterImpl, nlohmann::json_abi_v3_11_3::detail::iter_impl<BasicJsonType> >::value || std::is_same<IterImpl, nlohmann::json_abi_v3_11_3::detail::iter_impl<typename std::conditional<std::is_const<_Tp>::value, typename std::remove_const<_Tp>::type, const BasicJsonType>::type> >::value), std::nullptr_t>::type <anonymous> = nullptr; BasicJsonType = nlohmann::json_abi_v3_11_3::basic_json<>]: Assertion `m_object != nullptr' failed.
Program terminated with signal: SIGSEGV

Compiler and operating system

GCC 10.2

Library version

3.11.3

Validation

• The bug also occurs if the latest version from the develop branch is used.
• I can successfully compile and run the unit tests.