Repository navigation
Compilation error when building parse_v2.cpp #172
Description
While building for nixpkgs, we're encountering:
In file included from /nix/var/nix/builds/nix-build-python3.13-docling-parse-4.5.0.drv-0/b/source/app/parse_v2.cpp:3:
In file included from /nix/var/nix/builds/nix-build-python3.13-docling-parse-4.5.0.drv-0/b/source/src/v2.h:28:
In file included from /nix/store/5ibw2ya5h690yv3qs378x97q3ri7zjgg-nlohmann_json-3.12.0/include/nlohmann/json.hpp:40:
In file included from /nix/store/5ibw2ya5h690yv3qs378x97q3ri7zjgg-nlohmann_json-3.12.0/include/nlohmann/detail/input/binary_reader.hpp:29:
/nix/store/5ibw2ya5h690yv3qs378x97q3ri7zjgg-nlohmann_json-3.12.0/include/nlohmann/detail/input/json_sax.hpp:832:22: error: no matching conversion for functional-style cast from 'bool' to 'nlohmann::basic_json<>'
832 | auto value = BasicJsonType(std::forward<Value>(v));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~on Darwin:
-- cxx-compiler: /nix/store/l58v977vq4qy58m1bw60bzrpkywizz2b-clang-wrapper-21.1.1/bin/clang++
-- cxx-flags : -Wall -Wno-sign-compare -O3 -DROOT_PATH='"/nix/var/nix/builds/nix-build-python3.13-docling-parse-4.5.0.drv-0/b/source"'
-- cxx-standard: 20on Linux:
-- cxx-compiler: /nix/store/dmypp1h4ldn0vfk3fi6yfyf5yxp9yz0k-gcc-wrapper-14.3.0/bin/g++
-- cxx-flags : -Wall -Wno-sign-compare -O3 -DROOT_PATH='"/build/source"'
-- cxx-standard: 20nlohmann_json builds fine by itself and in many other packages, so we're not sure if this is triggered by something in v2.cpp beforehand.
Apologies for the limited information. Several of us have tried to resolve this and we're all stuck.
Reacted by Gaétan Lepage and Andrei Lapshin
Activity
sarahec commentedon Oct 11, 2025
sarahec commentedon Oct 11, 2025
Update: nlohmann_json 3.12.0 added many new conversions. From the release notes:
And your code depends on these conversions. But it turns out they're not always being included (see JSON_ImplicitConversions
I think our compiler setup on nixpkgs created the perfect storm to trigger teh nlohmann_json bug. It's not your issue and I'll close this now (for good).
test(T5): failing tests for DoclingParser + pin nixpkgs for docling