qt5,rpi_ws281x,hyperion,hyperhdr: fix Qt5 cross-compilation build - #11460
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Qt's build system uses INSTALL_ROOT as its staging variable, not DESTDIR.
With -sysroot in configure the default make install wrote to the live
sysroot; removing -sysroot and using INSTALL_ROOT="${INSTALL}" fixes that.
With -hostprefix "${TOOLCHAIN}" the generated cmake config files stored
mkspecs and host-tool paths referencing the toolchain directory, making
them unresolvable from the staging area.
Using -hostprefix /usr/host (a subdirectory of -prefix /usr) keeps all
paths self-contained within the staging area: host tools and mkspecs land
in usr/host/ while target libraries land in usr/lib/, cleanly separated.
The cmake configs use QT_HOST_DATA_RELATIVE to reference host items as
"host/..." relative to the install prefix, so they resolve correctly from
the staging area without symlinks or path fixups.
The source tree ships a plain-text version file in its root directory. When the directory is on a compiler include path, #include <version> (used by Qt5's qstdlibdetection.h) finds this file instead of the C++ standard library header and fails to compile with "error: stray '.' in program". Carry a patch to rename version to VERSION (safe on case-sensitive Linux) and update the file(READ) call in CMakeLists.txt. hyperhdr processes rpi_ws281x via add_subdirectory so cmake still reads the version data; hyperion compiles the sources directly and is unaffected either way. Patch submitted upstream: https://github.com/jgarff/rpi_ws281x pull 570 Drop this patch when the upstream PR is merged and PKG_VERSION is bumped.
Member
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please also bump PKG_REVs of hyperhdr and hyperion |
Qt5 is built with -sysroot removed and installs entirely under its own staging prefix rather than into the sysroot. The default cmake toolchain file sets CMAKE_FIND_ROOT_PATH_MODE_PACKAGE ONLY, so cmake cannot find Qt5's config files outside CMAKE_FIND_ROOT_PATH. Generate a thin wrapper toolchain file that includes the real LE toolchain and appends Qt5's staging prefix to CMAKE_FIND_ROOT_PATH. Pass this via PKG_CMAKE_OPTS_TARGET so it overrides the default toolchain file.
Same fix as hyperion: generate a thin cmake toolchain wrapper that includes the real LE toolchain and appends Qt5's staging prefix to CMAKE_FIND_ROOT_PATH so cmake can locate Qt5's config files.
Contributor
Author
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bumped |
HiassofT
approved these changes
Jun 11, 2026
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Summary
qt5
Two configure problems:
1.
-sysroot "${SYSROOT_PREFIX}"causedmake installto write to the live sysroot. Qt's build system usesINSTALL_ROOTas its staging variable (notDESTDIR); with-sysrootset, the default install bypassed staging entirely. Fix: remove-sysrootfrom configure and passINSTALL_ROOT="${INSTALL}"tomake install.2.
-hostprefix "${TOOLCHAIN}"baked the toolchain directory path into the generated cmake config files (Qt5CoreConfigExtras.cmake). Paths tomoc,mkspecsetc. were stored relative to the toolchain, making them unresolvable from the staging area. Using-hostprefix /usr/host(a subdirectory of-prefix /usr) keeps all cmake config paths self-contained within the staging area: Qt usesQT_HOST_DATA_RELATIVEto reference host items ashost/...relative to the install prefix. Host tools land inusr/host/bin/, target libraries inusr/lib/, cleanly separated.rpi_ws281x
The source tree ships a plain-text
versionfile in its root. When the directory is added to the compiler include path (as both hyperion and hyperhdr do),#include <version>- used by Qt5'sqstdlibdetection.h- finds this file instead of the C++20 standard library header, producingerror: stray '.' in program.hyperion / hyperhdr
Qt5 installs outside the sysroot (was suppose to given
PKG_BUILD_FLAGS="-sysroot"). LibreELEC's cmake toolchain setsCMAKE_FIND_ROOT_PATH_MODE_PACKAGE ONLY, so cmake cannot find Qt5's config files without an explicit path hint.Generate a thin wrapper toolchain file in
pre_configure_target()thatinclude()s the real LibreELEC toolchain then appends Qt5's staging prefix toCMAKE_FIND_ROOT_PATH. Passing-DCMAKE_TOOLCHAIN_FILE=viaPKG_CMAKE_OPTS_TARGEToverrides the default (last occurrence wins in cmake's command-line processing).Test plan