subagent transcript

session 17f09f89 · workflow wf_6c234df9
← 17f09f89 · archive
delegated task
GOAL: port PySide6 + shiboken6 to the FreeCAD WebAssembly toolchain (static, no-dlopen, asyncify, no-pthreads) so FreeCAD's Python/PySide workbenches
▸ Magik
GOAL: port PySide6 + shiboken6 to the FreeCAD WebAssembly toolchain (static, no-dlopen, asyncify, no-pthreads) so FreeCAD's Python/PySide workbenches and macros work in the browser. This is the keystone dependency. Ground EVERYTHING in the real files — investigate, do not speculate. ESTABLISHED GROUND TRUTH (verified this session): - PySide+shiboken SOURCE: /tmp/pyside-setup (git branch 6.11, matches Qt). sources/shiboken6, sources/shiboken6_generator, sources/pyside6 (check exact dir names). Built via setup.py + coin_build_instructions.py OR raw CMake per sources/*/CMakeLists.txt + README.*.md at repo root. - HOST toolchain (x86-64 Linux): clang/llvm 21 with libclang at /usr/lib/llvm-21/lib/libclang.so (llvm-config = 21.1.8); host CPython 3.14.4 (/usr/bin/python3, headers /opt/toolchains/src/Python-3.14.4/Include); host Qt 6.11.1 at /opt/toolchains/qt/6.11.1/gcc_64. - TARGET (wasm): emscripten 4.0.12 (/opt/toolchains/emsdk); Qt 6.11.1 asyncify single-thread at /opt/toolchains/qt-asyncify/6.11.1/wasm_singlethread (QT_FEATURE_thread == -1, i.e. -no-feature-thread); wasm CPython 3.14 at /opt/toolchains/python-wasm (headers include/python3.14, lib/python3.14.zip). FreeCAD-wasm build dir: /opt/toolchains/src/freecad-gui-build (reads Qt6_DIR=qt-asyncify/.../wasm_singlethread). - FreeCAD build links Python C-extensions STATICALLY and registers them via PyImport_AppendInittab in a generated src/Main/WasmInittab*.cpp (NO dlopen on wasm). PySide bindings must follow this model: build as STATIC libs, expose PyInit_* for each module (PySide6.QtCore etc.), register in the inittab. - FreeCAD source: /home/magik6k/lcad-wasm/freecad-port/FreeCAD (branch wasm-port). It ships a PySide shim at src/Ext/PySide (a compat layer) and uses shiboken (getCppPointer/wrapInstance) e.g. in Gui/PythonWrapper.cpp. FREECAD_USE_PYSIDE/FREECAD_USE_SHIBOKEN currently OFF. - KNOWN HARD ISSUES to design around: (1) static + NO dlopen — PySide's normal build emits shared modules; must emit static + inittab. (2) Qt is -no-feature-thread — shiboken typesystem for QtCore references QThread/QMutex/etc.; those must be excluded/guarded. (3) CPython 3.14 C-API changes vs what PySide 6.11 targets. (4) asyncify + JS-exceptions (-fexceptions) flags must match FreeCAD's; libshiboken/libpyside signal dispatch must be single-thread/asyncify safe. (5) binary size (wasm is already 196 MB; each Qt binding module is tens of MB — target ONLY the modules FreeCAD needs). DELIVERABLES — do BOTH: 1. Write a thorough, concrete, execution-ready plan to /home/magik6k/lcad-wasm/pyside-port/<SLUG>/plan.md with exact commands, cmake args, file paths, patch snippets (precise enough to apply), and any test outputs you gathered. Put patch/new-file contents as separate files in that dir. If you build/test something, capture the real output. 2. Return the structured summary (schema). Depth goes in plan.md; keep summary fields tight. Token cost is not a concern — be exhaustive and correct. Prefer running real commands (grep, ls, cmake --help, small test builds) over speculation. === YOUR SCOPE: The emscripten cross-compile setup for the bindings (slug: emscripten-crossbuild) === Define the emscripten toolchain setup to cross-compile libshiboken + libpyside + generated bindings for wasm: the emcmake/toolchain-file invocation, pointing at wasm CPython (/opt/toolchains/python-wasm) and wasm Qt (/opt/toolchains/qt-asyncify/6.11.1/wasm_singlethread), and the EXACT flags FreeCAD uses (grep /opt/toolchains/src/freecad-gui-build/CMakeCache.txt + src/Main/CMakeLists.txt for -sASYNCIFY, -fexceptions/-fwasm-exceptions, ASYNCIFY_STACK_SIZE, -sMAIN_MODULE/SIDE_MODULE, -O level, memory flags). The bindings MUST match FreeCAD's ABI (same exceptions model, same Python, same Qt). Note that the shiboken GENERATOR is host (x86) while the RUNTIME libs are wasm — a split build. Produce the toolchain file / cmake args. Create /home/magik6k/lcad-wasm/pyside-port/emscripten-crossbuild/ and write plan.md (required) + any patches. Return the schema with deliverableFile=/home/magik6k/lcad-wasm/pyside-port/emscripten-crossbuild/plan.md.
Fable
thinking
I need to dig into the actual FreeCAD build cache and CMakeLists files to find the exact compiler flags being used, so I'm going to search through those in parallel.
Fable
I'll investigate the real FreeCAD wasm build configuration to extract exact flags, then design the emscripten cross-build setup.
Fable
⚙ Bash {"command": "ls -la /opt/toolchains/src/freecad-gui-build/ 2>&1 | head -40; echo \"---CACHE EXISTS---\"; ls -la /opt/toolchains/src/freecad-gui-build/CMakeCache.txt 2>&1", "description": "List freecad build dir"}
tool result
total 24528
drwxr-xr-x 11 agent agent     4096 Jul  5 12:02 .
drwxr-xr-x 11 agent agent     4096 Jul  4 06:32 ..
-rw-r--r--  1 agent agent 12235588 Jul  5 12:00 .ninja_deps
-rw-r--r--  1 agent agent   516326 Jul  5 12:02 .ninja_log
drwxr-xr-x  2 agent agent     4096 Jul  5 11:50 .qt
-rw-r--r--  1 agent agent   300603 Jul  5 11:48 CMakeCache.txt
drwxr-xr-x  7 agent agent     4096 Jul  5 11:50 CMakeFiles
-rw-r--r--  1 agent agent      735 Jul  4 06:33 Coin.pc
drwxr-xr-x  4 agent agent     4096 Jul  …[truncated]
Fable
⚙ Bash {"command": "ls -la /opt/toolchains/python-wasm/ /opt/toolchains/python-wasm/lib/ /opt/toolchains/python-wasm/include/ 2>&1 | head -60", "description": "Inspect wasm python layout"}
tool result
/opt/toolchains/python-wasm/:
total 20
drwxr-xr-x  4 agent agent 4096 Jul  3 18:58 .
drwxr-xr-x 21 agent agent 4096 Jul  4 14:17 ..
drwxr-xr-x  3 agent agent 4096 Jul  3 18:58 include
drwxr-xr-x  3 agent agent 4096 Jul  3 19:02 lib
-rw-r--r--  1 agent agent  545 Jul  3 18:58 link-flags-reference.txt

/opt/toolchains/python-wasm/include/:
total 12
drwxr-xr-x 3 agent agent 4096 Jul  3 18:58 .
drwxr-xr-x 4 agent agent 4096 Jul  3 18:58 ..
drwxr-xr-x 4 agent agent 4096 Jul  3 18:58 python3.14

/opt/  …[truncated]
Fable
⚙ Bash {"command": "ls -la /opt/toolchains/qt-asyncify/6.11.1/wasm_singlethread/lib/cmake/ 2>&1 | head -40; echo \"---\"; ls /opt/toolchains/qt-asyncify/6.11.1/wasm_singlethread/ 2>&1", "description": "Inspect wasm Qt layout"}
tool result
total 164
drwxr-xr-x 39 agent agent  4096 Jul  4 06:21 .
drwxr-xr-x  4 agent agent  4096 Jul  4 06:21 ..
drwxr-xr-x  7 agent agent 12288 Jul  4 06:21 Qt6
drwxr-xr-x  4 agent agent  4096 Jul  4 06:21 Qt6BuildInternals
drwxr-xr-x  2 agent agent  4096 Jul  4 06:21 Qt6BundledLibjpeg
drwxr-xr-x  2 agent agent  4096 Jul  4 06:21 Qt6BundledLibjpeg12bits
drwxr-xr-x  2 agent agent  4096 Jul  4 06:21 Qt6BundledLibjpeg16bits
drwxr-xr-x  2 agent agent  4096 Jul  4 06:21 Qt6BundledLibpng
drwxr-xr-x  2 agent   …[truncated]
Fable
⚙ Bash {"command": "ls -la /tmp/pyside-setup/ 2>&1 | head; echo \"---SOURCES---\"; ls /tmp/pyside-setup/sources/ 2>&1", "description": "Check pyside source"}
tool result
total 192
drwxr-xr-x 14 agent agent  4096 Jul  5 11:02 .
drwxrwxrwt  1 root  root  20480 Jul  5 12:36 ..
-rw-r--r--  1 agent agent   279 Jul  5 11:02 .flake8
drwxr-xr-x  7 agent agent  4096 Jul  5 11:02 .git
-rw-r--r--  1 agent agent   416 Jul  5 11:02 .gitattributes
-rw-r--r--  1 agent agent  2012 Jul  5 11:02 .gitignore
-rw-r--r--  1 agent agent    86 Jul  5 11:02 .gitreview
drwxr-xr-x  2 agent agent  4096 Jul  5 11:02 .vscode
-rw-r--r--  1 agent agent  1024 Jul  5 11:02 CMakeLists.txt
---SOUR  …[truncated]
Fable
Let me extract the exact FreeCAD flags from the CMakeCache and build files.
Fable
⚙ Bash {"command": "cd /opt/toolchains/src/freecad-gui-build; echo \"=== EXCEPTION / ASYNCIFY / MODULE FLAGS in CMakeCache ===\"; grep -iE \"ASYNCIFY|fexceptions|fwasm-exceptions|wasm-exceptions|MAIN_MODULE|SIDE_MODULE|STACK_SIZE|INITIAL_MEMORY|AL…
tool result
=== EXCEPTION / ASYNCIFY / MODULE FLAGS in CMakeCache ===
CMAKE_CXX_FLAGS:STRING=-fexceptions -DEIGEN_DONT_VECTORIZE -DBOOST_HAS_PTHREADS=1 -DBOOST_STACKTRACE_USE_NOOP
CMAKE_C_FLAGS:STRING=-fexceptions -DXML_DEV_URANDOM
CMAKE_FIND_ROOT_PATH:UNINITIALIZED=/opt/toolchains/qt-asyncify/6.11.1/wasm_singlethread;/opt/toolchains/occt-wasm;/opt/toolchains/xerces-wasm;/opt/toolchains/fmt-wasm;/opt/toolchains/yaml-wasm;/opt/toolchains/python-wasm;/opt/toolchains/boost-wasm;/opt/toolchains/icu-wasm;/opt/to  …[truncated]
Fable
⚙ Bash {"command": "cd /opt/toolchains/src/freecad-gui-build; echo \"=== CMAKE FLAGS ===\"; grep -iE \"^CMAKE_CXX_FLAGS|^CMAKE_C_FLAGS|^CMAKE_EXE_LINKER|^CMAKE_MODULE_LINKER|^CMAKE_SHARED_LINKER|^CMAKE_BUILD_TYPE|^CMAKE_TOOLCHAIN|^CMAKE_CXX_STANDA…
tool result
=== CMAKE FLAGS ===
CMAKE_BUILD_TYPE:STRING=Release
CMAKE_CXX_FLAGS:STRING=-fexceptions -DEIGEN_DONT_VECTORIZE -DBOOST_HAS_PTHREADS=1 -DBOOST_STACKTRACE_USE_NOOP
CMAKE_CXX_FLAGS_DEBUG:STRING=-g
CMAKE_CXX_FLAGS_MINSIZEREL:STRING=-Os -DNDEBUG
CMAKE_CXX_FLAGS_RELEASE:STRING=-O3 -DNDEBUG
CMAKE_CXX_FLAGS_RELWITHDEBINFO:STRING=-O2 -g -DNDEBUG
CMAKE_CXX_STANDARD:STRING=11
CMAKE_C_FLAGS:STRING=-fexceptions -DXML_DEV_URANDOM
CMAKE_C_FLAGS_DEBUG:STRING=-g
CMAKE_C_FLAGS_MINSIZEREL:STRING=-Os -DNDEBUG
CMAKE  …[truncated]
Fable
thinking
I need to track down where the ASYNCIFY and memory linker flags are actually being applied to the final executable, since they should be in the main CMakeLists.txt file rather than elsewhere. Let me search through the build configuration to find where these flags are set.
Fable
The exceptions model is `-fexceptions` (emscripten legacy/JS exceptions, NOT wasm-exceptions), Release/-O3, C++11. Now let me find the ASYNCIFY/memory link flags — likely in src/Main/CMakeLists.txt and the final link line.
Fable
⚙ Bash {"command": "cd /home/magik6k/lcad-wasm/freecad-port/FreeCAD 2>/dev/null || cd /opt/toolchains/src; F=$(find /home/magik6k/lcad-wasm/freecad-port/FreeCAD/src/Main -name CMakeLists.txt 2>/dev/null | head -1); echo \"MAIN CMakeLists: $F\"; gr…
tool result
MAIN CMakeLists: /home/magik6k/lcad-wasm/freecad-port/FreeCAD/src/Main/CMakeLists.txt
8:if(EMSCRIPTEN)
10:    # must be registered on the interpreter's inittab before Py_Initialize().
52:    function(freecad_wasm_generate_inittab outfile)
67:            string(APPEND _regs "    PyImport_AppendInittab(\"${_pymod}\", PyInit_${_pymod});\n")
73:            "void freecadWasmRegisterInittab()\n"
78:    freecad_wasm_generate_inittab(${CMAKE_CURRENT_BINARY_DIR}/WasmInittab.cpp
80:    freecad_wasm_genera  …[truncated]
Fable
⚙ Bash {"command": "cd /opt/toolchains/src/freecad-gui-build; echo \"=== FINAL LINK LINE (FreeCADMain / .html/.js) from build.ninja ===\"; grep -oE \"\\-sASYNCIFY[^ ]*|ASYNCIFY_STACK_SIZE=[0-9]*|-sSTACK_SIZE=[0-9]*|-sINITIAL_MEMORY=[0-9]*|-sMAXIMU…
tool result
=== FINAL LINK LINE (FreeCADMain / .html/.js) from build.ninja ===
   2294 -fexceptions
      2 -sWASM_BIGINT
      2 -sSTACK_SIZE=5
      2 -sMODULARIZE
      2 -sMAXIMUM_MEMORY=4
      2 -sINITIAL_MEMORY=128
      2 -sEXPORT_NAME
      2 -sEXPORTED_RUNTIME_METHODS
      2 -sDISABLE_EXCEPTION_CATCHING=0
      2 -sALLOW_MEMORY_GROWTH=1
      1 -sFULL_ES3
      1 -sASYNCIFY_STACK_SIZE=67108864
      1 -sASYNCIFY=1
Fable
Let me read the full Main/CMakeLists.txt EMSCRIPTEN block to capture the exact common link options and inittab mechanism.
Fable
⚙ Read {"file_path": "/home/magik6k/lcad-wasm/freecad-port/FreeCAD/src/Main/CMakeLists.txt", "limit": 210}
tool result
1	# SPDX-License-Identifier: LGPL-2.1-or-later
2	
3	configure_file(freecad.rc.cmake ${CMAKE_CURRENT_BINARY_DIR}/freecad.rc)
4	configure_file(freecadCmd.rc.cmake ${CMAKE_CURRENT_BINARY_DIR}/freecadCmd.rc)
5	file(COPY icon.ico DESTINATION ${CMAKE_CURRENT_BINARY_DIR})
6	
7	
8	if(EMSCRIPTEN)
9	    # Python extension modules are linked statically into the executables and
10	    # must be registered on the interpreter's inittab before Py_Initialize().
11	    set(FREECAD_WASM_PY_MODULES "")
12	    set(  …[truncated]
Fable
thinking
I'm seeing that FreeCAD's bindings are compiled as static libraries and only need to match certain compile flags like the exceptions model, Python version, and Qt configuration. The actual async and memory flags are linker options applied to the final executable, not the static libs themselves. The key ABI considerations are the compile flags that affect how the code is built.

For the bindings specifically, I need to verify that they're using C++17 (which PySide 6.11 requires) even though FreeCAD globally sets C++11, since Qt propagates C++17 through its interface. The shiboken generator itself runs as a host tool on x86, while the runtime libraries and generated bindings are compiled for W  …
Fable
This gives me the complete ABI. Now let me gather the split-build specifics: emcc version, Python wasm sysconfig, host tools, and shiboken cross-build requirements.
Fable
⚙ Bash {"command": "source /opt/toolchains/emsdk/emsdk_env.sh 2>/dev/null; echo \"=== emcc version ===\"; emcc --version 2>&1 | head -3; echo \"=== EMSDK ===\"; echo $EMSDK; echo \"=== toolchain file ===\"; ls -la /opt/toolchains/emsdk/upstream/em…
tool result
=== emcc version ===
emcc (Emscripten gcc/clang-like replacement + linker emulating GNU ld) 4.0.12 (6f625bd62ee64f4f8cd11476774741b961e4a2d5)
Copyright (C) 2025 the Emscripten authors (see AUTHORS.txt)
This is free and open source software under the MIT license.
=== EMSDK ===
/opt/toolchains/emsdk
=== toolchain file ===
-rw-r--r-- 1 agent agent 19991 Aug  1  2025 /opt/toolchains/emsdk/upstream/emscripten/cmake/Modules/Platform/Emscripten.cmake
=== node ===
/opt/toolchains/emsdk/node/22.16.0_64bi  …[truncated]
Fable
⚙ Bash {"command": "cat /opt/toolchains/python-wasm/link-flags-reference.txt; echo \"=== python config dir ===\"; ls /opt/toolchains/python-wasm/lib/python3.14/ | grep -i config; find /opt/toolchains/python-wasm -name \"_sysconfigdata*\" 2>/dev/nu…
tool result
-lcov
-ldl
-level
-levenshtein
-lffi
-lidbfs
-limited
-linking
-linux
-list
-literal
-lm
-lmpdec
-lnodefs
-lproxyfs
-lpthread
-lt
-lworkerfs
-sALLOW_MEMORY_GROWTH
-sEXIT_RUNTIME
-sEXPORTED_FUNCTIONS=_main,_Py_Version,__PyRuntime,_PyGILState_GetThisThreadState,__Py_DumpTraceback,__PyEM_EMSCRIPTEN_TRAMPOLINE_OFFSET
-sEXPORTED_RUNTIME_METHODS=FS,callMain,ENV,HEAPU32,TTY,ERRNO_CODES
-sFORCE_FILESYSTEM
-sINITIAL_MEMORY=20971520
-sL
-sMAIN_MODULE
-sSIDE_MODULE=1
-sSTACK_SIZE=5MB
-sTEXTDECODER=2
-sUSE_  …[truncated]
Fable
⚙ Bash {"command": "echo \"=== host shiboken generator present? ===\"; find / -name \"shiboken6\" -type f 2>/dev/null | head; find / -name \"libshiboken*\" 2>/dev/null | head; echo \"=== host Qt for generator ===\"; ls /opt/toolchains/qt/6.11.1/gc…
tool result
=== host shiboken generator present? ===
/tmp/pyside-setup/sources/shiboken6/libshiboken
=== host Qt for generator ===
qmake
qmake6
=== libclang ===
lrwxrwxrwx 1 root root 40 Mar 18 15:52 /usr/lib/llvm-21/lib/libclang.so -> ../../x86_64-linux-gnu/libclang-21.so.21
Fable
thinking
So the wasm CPython build uses a static linking model rather than dynamic loading through dlopen, which means FreeCAD is embedding it as a MAIN_MODULE with SIDE_MODULE extensions. Now I need to look at how shiboken6 structures its CMake build to separate the generator from the runtime library — that's the critical piece for understanding how to cross-compile this setup.
Fable
Let me check the shiboken6/pyside6 CMake structure for the generator/runtime split and module selection options.
Fable
⚙ Bash {"command": "echo \"=== shiboken6 dir ===\"; ls /tmp/pyside-setup/sources/shiboken6/; echo \"=== top CMakeLists head ===\"; sed -n '1,60p' /tmp/pyside-setup/sources/shiboken6/CMakeLists.txt 2>/dev/null; echo \"=== grep options ===\"; grep -…
tool result
=== shiboken6 dir ===
AUTHORS
CMakeLists.txt
COPYING
COPYING.libsample
COPYING.libshiboken
Doxyfile
cmake
cmake_uninstall.cmake
config.tests
data
doc
generatorrunnerconfig.h.in
generatorrunnermacros.h
icecc.cmake
libshiboken
shiboken_version.py
shibokenmodule
tests
=== top CMakeLists head ===
# Copyright (C) 2023 The Qt Company Ltd.
# SPDX-License-Identifier: BSD-3-Clause

Include(icecc.cmake)

cmake_minimum_required(VERSION 3.22)
cmake_policy(VERSION 3.22)

set(CMAKE_BUILD_TYPE Release CACHE ST  …[truncated]
Fable
⚙ Bash {"command": "grep -rniE \"CMAKE_CROSSCOMPILING|python_for_shiboken|host.*generator|shiboken.*host|SHIBOKEN_PATH|QFP_|--shiboken|crossbuild|target-python\" /tmp/pyside-setup/sources/shiboken6/CMakeLists.txt /tmp/pyside-setup/sources/pyside6/…
tool result
=== pyside6 module selection ===
/tmp/pyside-setup/sources/pyside6/CMakeLists.txt:57:if(BUILD_TESTS)
=== coin cross build refs ===
Fable
thinking
So the repository structure separates the runtime library (libshiboken and its Python module) in sources/shiboken6 from the code generator in sources/shiboken6_generator, which uses libclang to generate bindings. The pyside6 directory contains the actual PySide bindings themselves.

Now I need to trace through how the generator gets invoked during the build — looking at ShibokenSetup.cmake and the helper functions like `create_generator_target` and the shiboken_generator command, then checking how pyside6's CMake finds and uses the generator through Shiboken6Tools and GeneratorRunner.
Fable
⚙ Bash {"command": "echo \"=== shiboken6_generator ===\"; ls /tmp/pyside-setup/sources/shiboken6_generator/; echo \"=== ShibokenSetup / helpers cmake files ===\"; ls /tmp/pyside-setup/sources/shiboken6/cmake/; echo \"=== how generator found by pys…
tool result
=== shiboken6_generator ===
ApiExtractor
CMakeLists.txt
cmake
data
generator
shiboken_tool.py
tests
=== ShibokenSetup / helpers cmake files ===
FindDocTools.cmake
ShibokenHelpers.cmake
ShibokenSetup.cmake
=== how generator found by pyside6 ===
/tmp/pyside-setup/sources/pyside6/cmake/PySideSetup.cmake:44:find_package(Shiboken6 6 CONFIG REQUIRED)
/tmp/pyside-setup/sources/pyside6/cmake/PySideSetup.cmake:259:    ${SHIBOKEN_GENERATOR_EXTRA_FLAGS}
/tmp/pyside-setup/sources/pyside6/cmake/PySideHelpers  …[truncated]
Fable
⚙ Bash {"command": "grep -rniE \"CMAKE_CROSSCOMPILING|python.*interpreter|Python.*Interpreter|shiboken_get_tool|use_pysidebuildtool|host_python|SHIBOKEN_PYTHON|python_config|libclang|LLVM|CLANG\" /tmp/pyside-setup/sources/shiboken6/cmake/ShibokenS…
tool result
/tmp/pyside-setup/sources/shiboken6/cmake/ShibokenSetup.cmake:45:message(STATUS "Python_Interpreter_FOUND:     " ${Python_Interpreter_FOUND})
/tmp/pyside-setup/sources/shiboken6/cmake/ShibokenSetup.cmake:62:if(NOT PYTHON_CONFIG_SUFFIX)
/tmp/pyside-setup/sources/shiboken6/cmake/ShibokenSetup.cmake:63:    set_python_config_suffix()
/tmp/pyside-setup/sources/shiboken6/cmake/ShibokenSetup.cmake:66:set(PYTHON_SHARED_LIBRARY_SUFFIX "${PYTHON_CONFIG_SUFFIX}")
/tmp/pyside-setup/sources/shiboken6/cmake/S  …[truncated]
Fable
thinking
So PySide's CMake setup already has built-in cross-compilation support through `QFP_SHIBOKEN_HOST_PATH` for the host-built generator and `QFP_SHIBOKEN_TARGET_PATH` for the target runtime, which is exactly the split build approach needed here.

Now I need to check how PySideHelpers.cmake and ShibokenHelpers.cmake actually use these paths, look for any existing wasm cross-compilation examples in the coin build configuration, and understand how libshiboken locates the Python installation when cross-compiling to wasm.
Fable
This is the key finding — PySide 6.11 has official cross-compile support via `QFP_SHIBOKEN_HOST_PATH` / `QFP_SHIBOKEN_TARGET_PATH`. Let me read the exact mechanism.
Fable
⚙ Read {"file_path": "/tmp/pyside-setup/sources/pyside6/cmake/PySideHelpers.cmake", "limit": 90}
tool result
1	# Copyright (C) 2023 The Qt Company Ltd.
2	# SPDX-License-Identifier: BSD-3-Clause
3	
4	function(pyside_internal_detect_if_cross_building)
5	    if(CMAKE_CROSSCOMPILING OR QFP_SHIBOKEN_HOST_PATH)
6	        set(is_cross_build TRUE)
7	    else()
8	        set(is_cross_build FALSE)
9	    endif()
10	    set(PYSIDE_IS_CROSS_BUILD "${is_cross_build}" PARENT_SCOPE)
11	    message(STATUS "PYSIDE_IS_CROSS_BUILD: ${PYSIDE_IS_CROSS_BUILD}")
12	endfunction()
13	
14	function(pyside_internal_set_up_extra_de  …[truncated]
Fable
⚙ Bash {"command": "grep -rniE \"wasm|emscripten|QFP_SHIBOKEN_HOST_PATH|QFP_SHIBOKEN_TARGET_PATH|shiboken-host-path|CMAKE_TOOLCHAIN|cross\" /tmp/pyside-setup/build_scripts/*.py /tmp/pyside-setup/*.py 2>/dev/null | grep -iE \"wasm|emscript|shiboken…
tool result
/tmp/pyside-setup/create_wheels.py:26:PYSIDE_DESCRIPTION = "Python bindings for the Qt cross-platform application and UI framework"
/tmp/pyside-setup/build_scripts/config.py:60:        # Path to CMake toolchain file when intending to cross compile
/tmp/pyside-setup/build_scripts/config.py:62:        self.cmake_toolchain_file: str | os.PathLike = ""
/tmp/pyside-setup/build_scripts/config.py:64:        # Store where host shiboken is built during a cross-build.
/tmp/pyside-setup/build_scripts/confi  …[truncated]
Fable
thinking
PySide 6.11 supports cross-compilation to WebAssembly with environment variables that specify paths for the target Qt installation, target Python, the shiboken runtime built during compilation, and the host shiboken generator.

Rather than using setup.py with its toolchain file, I'm designing a three-stage CMake build that gives more control over static linking and compilation flags. Stage A builds the shiboken generator and tools on the host machine. Stage B cross-compiles just the shiboken runtime library for WebAssembly using the emscripten toolchain and exception handling flags. Stage C then builds PySide6 itself for WebAssembly, linking against the wasm shiboken runtime from Stage B.

T  …
Fable
PySide 6.11 has full official cross-compile support. Let me verify the Python-finding logic in ShibokenHelpers and check how the generator target is exposed, plus the standard module library type (the shared-vs-static concern).
Fable
⚙ Bash {"command": "echo \"=== find_package Python in shiboken ===\"; grep -rniE \"find_package.Python|Python3_EXECUTABLE|Python_EXECUTABLE|Python3_LIBRARIES|Python_LIBRARIES|Python3_INCLUDE|Development.Module|Interpreter|find_python_libs\" /tmp/p…
tool result
=== find_package Python in shiboken ===
/tmp/pyside-setup/sources/shiboken6/cmake/ShibokenSetup.cmake:43:message(STATUS "Python_LIBRARIES:       " ${Python_LIBRARIES})
/tmp/pyside-setup/sources/shiboken6/cmake/ShibokenSetup.cmake:45:message(STATUS "Python_Interpreter_FOUND:     " ${Python_Interpreter_FOUND})
/tmp/pyside-setup/sources/shiboken6/cmake/ShibokenSetup.cmake:46:message(STATUS "Python_EXECUTABLE:      " ${Python_EXECUTABLE})
/tmp/pyside-setup/sources/shiboken6/cmake/ShibokenSetup.cmake  …[truncated]
Fable
thinking
I'm checking the ShibokenHelpers code around line 303-340 where it handles cross-compilation Python detection without actually executing the target interpreter.
Fable
Let me read the cross-compile Python-finding block in ShibokenHelpers (line ~300-345) — it explicitly handles the "can't execute target interpreter" case.
Fable
⚙ Read {"file_path": "/tmp/pyside-setup/sources/shiboken6/cmake/ShibokenHelpers.cmake", "offset": 295, "limit": 55}
tool result
295	            "${CMAKE_FIND_ROOT_PATH_MODE_PROGRAM}")
296	        set(_shiboken_backup_CMAKE_FIND_ROOT_PATH
297	            "${CMAKE_FIND_ROOT_PATH}")
298	        set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM ONLY)
299	        if(Python_ROOT_DIR)
300	            list(PREPEND CMAKE_FIND_ROOT_PATH "${Python_ROOT_DIR}")
301	        endif()
302	
303	        # We can't look for the Python interpreter because FindPython tries to execute it, which
304	        # usually won't work on a host platform due to di  …[truncated]
Fable
thinking
I'm verifying that the wasm Python's Development component will be discoverable by FindPython, which needs to locate the include directory with Python headers and the static library file. The wasm build has both of these in place, but I need to check whether FindPython's detection logic will actually find them.

I'm also looking at the SOABI string from sysconfigdata to understand how module naming works in this cross-compilation setup, and confirming that the emscripten toolchain properly sets CMAKE_SYSTEM_NAME so CMake recognizes this as a cross-compile. Finally, I need to verify the host Python version matches and that the host shiboken generator has its clang dependency available.
Fable
⚙ Bash {"command": "grep -iE \"'SOABI'|'EXT_SUFFIX'|'MULTIARCH'|'Py_ENABLE_SHARED'|'VERSION'\" /opt/toolchains/python-wasm/lib/python3.14/_sysconfigdata__emscripten_wasm32-emscripten.py | head; echo \"=== emscripten toolchain sets SYSTEM_NAME ===\…
tool result
    'EXT_SUFFIX': '.cpython-314-wasm32-emscripten.so',
    'MULTIARCH': 'wasm32-emscripten',
    'PY_ENABLE_SHARED': 0,
    'Py_ENABLE_SHARED': 0,
    'SOABI': 'cpython-314-wasm32-emscripten',
    'VERSION': '3.14',
=== emscripten toolchain sets SYSTEM_NAME ===
# It teaches CMake about the Emscripten compiler, so that CMake can generate
# cmake -DCMAKE_TOOLCHAIN_FILE=<EmscriptenRoot>/cmake/Modules/Platform/Emscripten.cmake
set(CMAKE_SYSTEM_NAME Emscripten)
set(CMAKE_CROSSCOMPILING TRUE)
# Advert  …[truncated]
Fable
thinking
With Emscripten's toolchain configuration setting CMAKE_SYSTEM_NAME and CMAKE_CROSSCOMPILING, PySide automatically activates its cross-compilation path, which generates the SOABI and EXT_SUFFIX values for WebAssembly. The code generator relies on libclang from the host LLVM installation to process the build.
Fable
⚙ Bash {"command": "find /tmp/pyside-setup/sources/shiboken6_generator -iname \"*clang*.cmake\" 2>/dev/null; grep -rniE \"LLVM_INSTALL_DIR|CLANG_INSTALL_DIR|llvm-config|ENV\\{\" /tmp/pyside-setup/sources/shiboken6_generator/cmake/*.cmake 2>/dev/nu…
tool result
/tmp/pyside-setup/sources/shiboken6_generator/cmake/ShibokenGeneratorHelpers.cmake:4:    # Find libclang using the environment variables LLVM_INSTALL_DIR,
/tmp/pyside-setup/sources/shiboken6_generator/cmake/ShibokenGeneratorHelpers.cmake:5:    # CLANG_INSTALL_DIR using standard cmake.
/tmp/pyside-setup/sources/shiboken6_generator/cmake/ShibokenGeneratorHelpers.cmake:7:    if(DEFINED ENV{LLVM_INSTALL_DIR})
/tmp/pyside-setup/sources/shiboken6_generator/cmake/ShibokenGeneratorHelpers.cmake:8:        …[truncated]
Fable
I have complete grounding. Now let me write the deliverables: the toolchain file, the three-stage build scripts, and plan.md.
Fable
⚙ Bash {"command": "mkdir -p /home/magik6k/lcad-wasm/pyside-port/emscripten-crossbuild; echo done", "description": "Create deliverable dir"}
tool result
done
Fable
thinking
I'm setting up the build infrastructure with a CMake toolchain that wraps emscripten and pins the ABI flags, then creating three shell scripts to handle building the host shiboken generator, the wasm shiboken runtime, and finally the wasm pyside bindings. I'll also document the overall plan in markdown.
Fable
⚙ Write {"file_path": "/home/magik6k/lcad-wasm/pyside-port/emscripten-crossbuild/pyside-wasm-toolchain.cmake", "content": "# pyside-wasm-toolchain.cmake\n# -----------------------------------------------------------------------------\n# CMake toolc…
tool result
File created successfully at: /home/magik6k/lcad-wasm/pyside-port/emscripten-crossbuild/pyside-wasm-toolchain.cmake (file state is current in your context — no need to Read it back)
Fable
thinking
Writing build scripts...
Fable
⚙ Write {"file_path": "/home/magik6k/lcad-wasm/pyside-port/emscripten-crossbuild/01-build-host-shiboken.sh", "content": "#!/usr/bin/env bash\n# =============================================================================\n# STAGE A (HOST / x86-64)…
tool result
File created successfully at: /home/magik6k/lcad-wasm/pyside-port/emscripten-crossbuild/01-build-host-shiboken.sh (file state is current in your context — no need to Read it back)
Fable
⚙ Write {"file_path": "/home/magik6k/lcad-wasm/pyside-port/emscripten-crossbuild/02-build-wasm-shiboken-runtime.sh", "content": "#!/usr/bin/env bash\n# =============================================================================\n# STAGE B (TARGET…
tool result
File created successfully at: /home/magik6k/lcad-wasm/pyside-port/emscripten-crossbuild/02-build-wasm-shiboken-runtime.sh (file state is current in your context — no need to Read it back)
Fable
⚙ Write {"file_path": "/home/magik6k/lcad-wasm/pyside-port/emscripten-crossbuild/03-build-wasm-pyside.sh", "content": "#!/usr/bin/env bash\n# =============================================================================\n# STAGE C (TARGET / wasm): …
tool result
File created successfully at: /home/magik6k/lcad-wasm/pyside-port/emscripten-crossbuild/03-build-wasm-pyside.sh (file state is current in your context — no need to Read it back)
Fable
Now let me do a quick real validation: attempt the host generator configure to confirm the toolchain/libclang path works, since that's the most testable non-wasm piece and gates everything.
Fable
⚙ Bash {"command": "cd /tmp; export LLVM_INSTALL_DIR=/usr/lib/llvm-21; rm -rf /tmp/sbk-host-test; mkdir -p /tmp/sbk-host-test\ntimeout 240 cmake -G Ninja -S /tmp/pyside-setup/sources/shiboken6 -B /tmp/sbk-host-test \\\n -DCMAKE_BUILD_TYPE=Release…
tool result
-- SHIBOKEN_PYTHON_LIBRARIES computed to value: ''
-- Performing Test HAVE_FFI_CALL
-- Performing Test HAVE_FFI_CALL - Success
-- Found FFI: /usr/lib/x86_64-linux-gnu/libffi.so
-- Could NOT find LibEdit (missing: LibEdit_INCLUDE_DIRS LibEdit_LIBRARIES) 
-- Found ZLIB: /usr/lib/x86_64-linux-gnu/libz.so (found version "1.3.1")
-- Could NOT find zstd (missing: zstd_LIBRARY zstd_INCLUDE_DIR) 
-- Found LibXml2: /usr/lib/x86_64-linux-gnu/libxml2.so (found version "2.15.2")
-- Could NOT find CURL (miss  …[truncated]
Fable
thinking
I'm realizing there's a circular dependency issue here: the shiboken runtime in `sources/shiboken6` contains a `shibokenmodule` subdirectory that actually needs the shiboken generator (from `sources/shiboken6_generator`) to build itself, since the Python module is generated by the generator. This means I can't build the runtime alone—the generator has to be built first or in parallel during Stage A. So the issue is that my Stage A script builds shiboken6 before shiboken6_generator, which is backwards — shiboken6 needs to find the generator via `find_package(Shiboken6Tools)` but it's not available yet. The shibokenmodule references `Shiboken6::shiboken6` which the generator provides, so when   …
Fable
Important finding — standalone `shiboken6` runtime build needs the generator target `Shiboken6::shiboken6`. Let me check the real build ordering and how the generator target is provided.
Fable
⚙ Bash {"command": "echo \"=== shibokenmodule/CMakeLists line 1-30 ===\"; sed -n '1,30p' /tmp/pyside-setup/sources/shiboken6/shibokenmodule/CMakeLists.txt; echo \"=== find_package Shiboken6Tools in shiboken6? ===\"; grep -rniE \"find_package|Shibo…
tool result
=== shibokenmodule/CMakeLists line 1-30 ===
# Copyright (C) 2023 The Qt Company Ltd.
# SPDX-License-Identifier: BSD-3-Clause

project(shibokenmodule)

configure_file("${CMAKE_CURRENT_SOURCE_DIR}/shibokenmodule.txt.in"
               "${CMAKE_CURRENT_BINARY_DIR}/shibokenmodule.txt" @ONLY)

set(sample_SRC ${CMAKE_CURRENT_BINARY_DIR}/Shiboken/shiboken_module_wrapper.cpp)

set(shibokenmodule_TYPESYSTEM ${CMAKE_CURRENT_SOURCE_DIR}/typesystem_shiboken.xml)

shiboken_get_tool_shell_wrapper(shiboken too  …[truncated]
Fable
⚙ Bash {"command": "echo \"=== build order in coin/setup ===\"; grep -rniE \"shiboken6_generator|shiboken6|pyside6|BUILD_SHIBOKEN|standalone|add_subdirectory\" /tmp/pyside-setup/build_scripts/main.py 2>/dev/null | head -20; echo \"=== is there a s…
tool result
=== build order in coin/setup ===
/tmp/pyside-setup/build_scripts/main.py:268:        site-packages/PySide6 directory when the command is 'install'
/tmp/pyside-setup/build_scripts/main.py:446:                _project = "shiboken6"
/tmp/pyside-setup/build_scripts/main.py:448:                _project = "shiboken6_generator"
/tmp/pyside-setup/build_scripts/main.py:450:                _project = "PySide6"
/tmp/pyside-setup/build_scripts/main.py:458:                # This applies to 'shiboken6', 'shi  …[truncated]
Fable
thinking
I'm realizing the CMakeLists.txt at the top level orchestrates a specific build sequence where the shiboken6 generator gets built first, then shiboken6 itself, both contributing to the final `Shiboken6::shiboken6` target that shibokenmodule depends on. The generator's build directory gets added to CMAKE_PREFIX_PATH so shiboken6 can locate the necessary tools. There's a wrinkle with cross-compilation I need to think through. The issue is that standalone shiboken6 can't find Shiboken6Tools through find_package — it only works inside the superproject via add_subdirectory. So for a cross-build, the cleanest approach is to build shiboken6_generator first, then point shiboken6's CMAKE_PREFIX_PATH   …
Fable
The superproject builds `shiboken6_generator` before `shiboken6` — so my Stage A ordering is wrong (generator must come first). Let me find how standalone `shiboken6` imports the generator target, then fix the script.
Fable
⚙ Bash {"command": "grep -rniE \"find_package.*Shiboken6Tools|Shiboken6Tools|import.*generator|shiboken_get_tool_shell_wrapper|Shiboken6::shiboken6\" /tmp/pyside-setup/sources/shiboken6/cmake/*.cmake /tmp/pyside-setup/sources/shiboken6/data/*.cmak…
tool result
/tmp/pyside-setup/sources/shiboken6/data/GeneratorRunnerConfig.cmake.in:10:    SET(GENERATORRUNNER_LIBRARY "@LIB_INSTALL_DIR@/@CMAKE_IMPORT_LIBRARY_PREFIX@genrunner@generator_SUFFIX@@CMAKE_IMPORT_LIBRARY_SUFFIX@")
/tmp/pyside-setup/sources/shiboken6/cmake/ShibokenHelpers.cmake:534:    set(SHIBOKEN6TOOLS_SKIP_FIND_DEPENDENCIES TRUE)
/tmp/pyside-setup/sources/shiboken6/cmake/ShibokenHelpers.cmake:536:        Shiboken6Tools 6 CONFIG
/tmp/pyside-setup/sources/shiboken6/cmake/ShibokenHelpers.cmake:54  …[truncated]
Fable
thinking
I'm tracing through how shiboken6's runtime build locates its tools—specifically looking at the ShibokenHelpers.cmake file around line 534 where it calls find_package(Shiboken6Tools) and how QFP_SHIBOKEN_HOST_PATH factors into this mechanism, even during the shibokenmodule configuration phase.
Fable
`shiboken6` runtime calls `find_package(Shiboken6Tools)` and honors `QFP_SHIBOKEN_HOST_PATH`. Let me read that block to fix Stage A/B ordering correctly.
Fable
⚙ Read {"file_path": "/tmp/pyside-setup/sources/shiboken6/cmake/ShibokenHelpers.cmake", "offset": 520, "limit": 50}
tool result
520	        set(_shiboken_build_tests_default OFF)
521	    elseif(SHIBOKEN_BUILD_LIBS)
522	        set(_shiboken_build_tests_default ON)
523	    endif()
524	    option(BUILD_TESTS "Build tests." ${_shiboken_build_tests_default})
525	    message(STATUS "BUILD_TESTS: ${BUILD_TESTS}")
526	endfunction()
527	
528	function(shiboken_internal_find_host_shiboken_tools)
529	    set(find_package_extra_args)
530	    if(QFP_SHIBOKEN_HOST_PATH)
531	        list(APPEND find_package_extra_args PATHS "${QFP_SHIB  …[truncated]
Fable
thinking
So the shiboken6 runtime uses environment variables like `QFP_SHIBOKEN_HOST_PATH` and `QFP_QT_TARGET_PATH` to locate the host generator during cross-compilation, which provides the necessary Shiboken6::shiboken6 target for generating the shibokenmodule. In my earlier host-only test, I was checking how this worked when cross-compilation was disabled and the path was unset, which caused the find_host step to be skipped and the target to be missing—that's why it failed. A standalone shiboken6 build genuinely needs the generator either built in-tree or provided via the tools package.

The corrected approach splits into three stages: first, build just the shiboken6_generator on the host, which in  …
Fable
Confirmed: `QFP_SHIBOKEN_HOST_PATH` drives the generator lookup in the wasm runtime build. My Stage A must build the generator FIRST (and it's all that's needed on host). Let me validate the generator configures on host (libclang discovery is the gating risk), then fix the scripts.
Fable
⚙ Bash {"command": "export LLVM_INSTALL_DIR=/usr/lib/llvm-21; rm -rf /tmp/sbk-gen-test; mkdir -p /tmp/sbk-gen-test\ntimeout 240 cmake -G Ninja -S /tmp/pyside-setup/sources/shiboken6_generator -B /tmp/sbk-gen-test \\\n -DCMAKE_BUILD_TYPE=Release \…
tool result
-- Found Python: /usr/bin/python3 (found version "3.14.4") found components: Interpreter Development.Module
-- Found ZLIB: /usr/lib/x86_64-linux-gnu/libz.so (found version "1.3.1")
-- Found LibXml2: /usr/lib/x86_64-linux-gnu/libxml2.so (found version "2.15.2")
-- CLANG: /usr/lib/llvm-21/lib/cmake/clang, /usr/lib/llvm-21/lib/libclang-21.so.21 detected
-- Found Git: /usr/bin/git (found version "2.53.0")
-- Found LibXml2: /usr/lib/x86_64-linux-gnu/libxml2.so (found suitable version "2.15.2", minimu  …[truncated]
Fable
thinking
The host generator setup is working correctly with libclang 21, Python 3.14.4, and Qt6 all detected properly, which confirms Stage A is valid. Now I need to refine the build scripts to ensure the generator builds in isolation and verify the correct sequencing between stages.

Rewriting the first build script...
Fable
The host generator configures cleanly — libclang-21 detected, Python 3.14.4, Qt6 found. This validates Stage A. Now let me correct the scripts: Stage A builds only the generator (it's all the host needs), and Stage B passes `QFP_SHIBOKEN_HOST_PATH`.
Fable
⚙ Write {"file_path": "/home/magik6k/lcad-wasm/pyside-port/emscripten-crossbuild/01-build-host-shiboken.sh", "content": "#!/usr/bin/env bash\n# =============================================================================\n# STAGE A (HOST / x86-64)…
tool result
The file /home/magik6k/lcad-wasm/pyside-port/emscripten-crossbuild/01-build-host-shiboken.sh has been updated successfully. (file state is current in your context — no need to Read it back)
Fable
⚙ Edit {"replace_all": false, "file_path": "/home/magik6k/lcad-wasm/pyside-port/emscripten-crossbuild/02-build-wasm-shiboken-runtime.sh", "old_string": "cmake -G Ninja -S \"$SRC/shiboken6\" -B \"$BUILD\" \\\n -DCMAKE_TOOLCHAIN_FILE=\"$TOOLCHAIN…
tool result
The file /home/magik6k/lcad-wasm/pyside-port/emscripten-crossbuild/02-build-wasm-shiboken-runtime.sh has been updated successfully. (file state is current in your context — no need to Read it back)
Fable
thinking
I'm considering whether to do a full test-configure of Stage B with the wasm shiboken runtime to validate the entire toolchain end-to-end, but that requires building the host generator first which would take several minutes. I could either start that build in the background with a time limit, or test-configure Stage B without the host path to at least verify the toolchain file loads correctly.

Actually, the most direct approach is to create a minimal CMake project that uses find_package for Qt6 Core and Python Development with my toolchain file — that validates the core deliverable (wasm Qt and Python discovery) without needing the full generator build.
Fable
Let me validate the toolchain file itself resolves wasm Qt + wasm Python via a tiny probe project, and kick off the host generator build in the background for a fuller Stage B test.
Fable
⚙ Bash {"command": "cd /opt/toolchains/src/pyside-host-gen-build 2>/dev/null && echo \"gen build dir exists\"; export LLVM_INSTALL_DIR=/usr/lib/llvm-21; mkdir -p /opt/toolchains/src/pyside-host-gen-build; cd /tmp/pyside-setup/sources/shiboken6_gen…
tool result
Command running in background with ID: bq7s7cddd. Output is being written to: /tmp/claude-1000/-home-magik6k-lcad-wasm/17f09f89-ce7c-4f49-aa6a-cf0521026805/tasks/bq7s7cddd.output. You will be notified when it completes. To check interim output, use Read on that file path.
Fable
⚙ Bash {"command": "mkdir -p /tmp/tc-probe; cat > /tmp/tc-probe/CMakeLists.txt <<'EOF'\ncmake_minimum_required(VERSION 3.22)\nproject(tcprobe CXX)\nfind_package(Qt6 REQUIRED COMPONENTS Core Gui Widgets)\nmessage(STATUS \"PROBE Qt6_VERSION=${Qt6_VE…
tool result
-- Found ZLIB: /opt/toolchains/emsdk/upstream/emscripten/cache/sysroot/lib/wasm32-emscripten/libz.a (found version "1.3.1")
-- Found EGL: /opt/toolchains/emsdk/upstream/emscripten/cache/sysroot/include (found version "1.5")
-- Found WrapSystemFreetype: /opt/toolchains/emsdk/upstream/emscripten/cache/sysroot/lib/wasm32-emscripten/libfreetype.a (found version "2.13.3")
-- PROBE Qt6_VERSION=6.11.1
-- PROBE Qt6Core_DIR=/opt/toolchains/qt-asyncify/6.11.1/wasm_singlethread/lib/cmake/Qt6Core
-- PROBE P  …[truncated]
Fable
thinking
I'm verifying the complete toolchain configuration where Qt6 and Python resolve to their WebAssembly variants, and the compiler flags are set to enable exceptions while matching FreeCAD's ABI requirements for an Emscripten cross-compilation build.

The configuration is solid—the toolchain file and emcmake setup work correctly, and the key proof is that find_package resolution and the flags are properly configured. Now I'll document the full plan in a comprehensive markdown file while the background generator build completes.
Fable
Toolchain file validated end-to-end: Qt6 6.11.1 resolves to the wasm asyncify/singlethread path, Python 3.14.4 to wasm libpython, and `CMAKE_CXX_FLAGS=-fexceptions -sDISABLE_EXCEPTION_CATCHING=0` (FreeCAD ABI match), cross-build active. Now let me write the comprehensive plan.md while the generator builds.
Fable
⚙ Write {"file_path": "/home/magik6k/lcad-wasm/pyside-port/emscripten-crossbuild/plan.md", "content": "# PySide6 / shiboken6 — Emscripten cross-compile toolchain for the FreeCAD wasm target\n\n**Scope (slug `emscripten-crossbuild`):** the emscripte…
tool result
File created successfully at: /home/magik6k/lcad-wasm/pyside-port/emscripten-crossbuild/plan.md (file state is current in your context — no need to Read it back)
Fable
thinking
The host generator build succeeded, so I should verify the binary is actually there and functional, then potentially move on to testing the Stage B configuration.
Fable
The host generator build finished (exit 0). Let me verify the binary and then test-configure Stage B (wasm runtime) end-to-end.
Fable
⚙ Bash {"command": "ls -la /opt/toolchains/pyside-host/bin/shiboken6 2>&1; /opt/toolchains/pyside-host/bin/shiboken6 --version 2>&1 | head -3; echo \"=== Shiboken6Tools pkg ===\"; ls /opt/toolchains/pyside-host/lib/cmake/ 2>&1", "description": "Ve…
tool result
-rwxr-xr-x 1 agent agent 4730280 Jul  5 12:43 /opt/toolchains/pyside-host/bin/shiboken6
shiboken v6.11.0
Copyright (C) 2016 The Qt Company Ltd.
=== Shiboken6Tools pkg ===
Shiboken6Tools
Fable
The host generator (`shiboken6 v6.11.0`) built and installed, and the `Shiboken6Tools` package is present. Now let me test-configure Stage B (wasm runtime) to validate the full cross-build wiring.
Fable
⚙ Bash {"command": "source /opt/toolchains/emsdk/emsdk_env.sh >/dev/null 2>&1\nrm -rf /tmp/sbk-wasm-test\ntimeout 300 cmake -G Ninja -S /tmp/pyside-setup/sources/shiboken6 -B /tmp/sbk-wasm-test \\\n -DCMAKE_TOOLCHAIN_FILE=/home/magik6k/lcad-wasm/…
tool result
-- SHIBOKEN_IS_CROSS_BUILD: TRUE
-- Python_Development_FOUND:       TRUE
-- Python_LIBRARIES:       /opt/toolchains/python-wasm/lib/libpython3.14.a
-- Python_INCLUDE_DIRS:    /opt/toolchains/python-wasm/include/python3.14
-- Python_Interpreter_FOUND:     FALSE
-- Python_EXECUTABLE:      
-- Python_VERSION:         3.14.4
-- PYTHON_EXTENSION_SUFFIX: .cpython-314-wasm32-emscripten
-- PYTHON_LIMITED_LIBRARIES: 
-- PYTHON_EXTENSION_SUFFIX:      .cpython-314-wasm32-emscripten
-- PYTHON_CONFIG_SUFFIX:  …[truncated]
Fable
thinking
Stage B is configuring successfully with the cross-build flag enabled, Python discovered through development headers with the wasm libpython library, and the extension suffix properly set for WebAssembly. Shiboken6Tools and the shiboken6 target are both available without any fatal errors.

The validation confirms the toolchain file and QFP_SHIBOKEN_HOST_PATH mechanism work end-to-end: the host generator built and ran in Stage A, and Stage B is now configuring correctly in cross-build mode with host tools accessible. The empty SHIBOKEN_PYTHON_LIBRARIES value is expected for wasm since the module doesn't link Python directly—symbols resolve at final link time, matching the no-dlopen model.

I'  …
Fable
Stage B configures cleanly end-to-end: `SHIBOKEN_IS_CROSS_BUILD: TRUE`, host `Shiboken6Tools`/`Shiboken6::shiboken6` resolved (no FATAL, no missing-target error), wasm Python found via Development-only (no interpreter execution), `PYTHON_EXTENSION_SUFFIX=.cpython-314-wasm32-emscripten`, Configuring+Generating done. The full cross-build wiring is verified. Let me finalize.
Fable
⚙ Bash {"command": "chmod +x /home/magik6k/lcad-wasm/pyside-port/emscripten-crossbuild/*.sh; ls -la /home/magik6k/lcad-wasm/pyside-port/emscripten-crossbuild/", "description": "Make scripts executable and list deliverables"}
tool result
total 36
drwxr-xr-x 1 agent agent   230 Jul  5 12:45 .
drwxr-xr-x 1 agent agent   246 Jul  5 12:44 ..
-rwxr-xr-x 1 agent agent  2455 Jul  5 12:43 01-build-host-shiboken.sh
-rwxr-xr-x 1 agent agent  3294 Jul  5 12:43 02-build-wasm-shiboken-runtime.sh
-rwxr-xr-x 1 agent agent  2924 Jul  5 12:40 03-build-wasm-pyside.sh
-rw-r--r-- 1 agent agent 15381 Jul  5 12:45 plan.md
-rw-r--r-- 1 agent agent  5532 Jul  5 12:40 pyside-wasm-toolchain.cmake
Fable
⚙ StructuredOutput {"__unparsedToolInput": {"raw": "{\"slug\": \"emscripten-crossbuild\", \"title\": \"Emscripten cross-compile toolchain for PySide6/shiboken6 (FreeCAD wasm ABI)\", \"verdict\": \"Delivered a verified split-build toolchain. shiboken's generat…
tool result
<tool_use_error>InputValidationError: StructuredOutput was called with input that could not be parsed as JSON.
You sent (first 200 of 5285 bytes): {"slug": "emscripten-crossbuild", "title": "Emscripten cross-compile toolchain for PySide6/shiboken6 (FreeCAD wasm ABI)", "verdict": "Delivered a verified split-build toolchain. shiboken's generator i
Common causes: unescaped backslashes in file paths (use / or \\), unescaped control characters, or truncated output. Retry with valid JSON.</tool_use_er  …[truncated]
Fable
I'll resend with properly structured fields.
Fable
⚙ StructuredOutput {"__unparsedToolInput": {"raw": "{\"slug\": \"emscripten-crossbuild\", \"title\": \"Emscripten cross-compile toolchain for PySide6/shiboken6 (FreeCAD wasm ABI)\", \"verdict\": \"Delivered a verified split-build toolchain. shiboken's generat…
tool result
<tool_use_error>InputValidationError: StructuredOutput was called with input that could not be parsed as JSON.
You sent (first 200 of 5008 bytes): {"slug": "emscripten-crossbuild", "title": "Emscripten cross-compile toolchain for PySide6/shiboken6 (FreeCAD wasm ABI)", "verdict": "Delivered a verified split-build toolchain. shiboken's generator i
Common causes: unescaped backslashes in file paths (use / or \\), unescaped control characters, or truncated output. Retry with valid JSON.</tool_use_er  …[truncated]
Fable
thinking
I see the problem—I'm wrapping the data incorrectly and the blockers array isn't properly formatted. Let me restructure this to use the actual schema fields directly, making sure blockers is a clean array of strings.
Fable
⚙ StructuredOutput {"slug": "emscripten-crossbuild", "title": "Emscripten cross-compile toolchain for PySide6/shiboken6 (FreeCAD wasm ABI)", "verdict": "Delivered a verified split-build toolchain. shiboken's generator is host x86-64 (links libclang-21); libsh…
tool result
Structured output provided successfully