Bug 241182

In order to reproduce, the easiest is to check out Buildroot commit eb5e2d2d43c5c0f71ae8243081625261de2cd134, and use the following snippet as a defconfig: % cat > configs/wpewebkit_neon_defconfig <<EOF BR2_arm=y BR2_cortex_a72=y BR2_ARM_FPU_NEON_VFPV4=y BR2_PER_PACKAGE_DIRECTORIES=y BR2_TOOLCHAIN_EXTERNAL=y BR2_SYSTEM_DHCP="eth0" BR2_ROOTFS_POST_BUILD_SCRIPT="board/raspberrypi4/post-build.sh" BR2_ROOTFS_POST_IMAGE_SCRIPT="board/raspberrypi4/post-image.sh" BR2_LINUX_KERNEL=y BR2_LINUX_KERNEL_CUSTOM_TARBALL=y BR2_LINUX_KERNEL_CUSTOM_TARBALL_LOCATION="$(call github,raspberrypi,linux,0b54dbda3cca2beb51e236a25738784e90853b64)/linux-0b54dbda3cca2beb51e236a25738784e90853b64.tar.gz" BR2_LINUX_KERNEL_DEFCONFIG="bcm2711" BR2_LINUX_KERNEL_DTS_SUPPORT=y BR2_LINUX_KERNEL_INTREE_DTS_NAME="bcm2711-rpi-4-b" BR2_LINUX_KERNEL_NEEDS_HOST_OPENSSL=y BR2_PACKAGE_COG=y BR2_PACKAGE_MESA3D=y BR2_PACKAGE_MESA3D_GALLIUM_DRIVER_V3D=y BR2_PACKAGE_MESA3D_OPENGL_ES=y BR2_PACKAGE_RPI_FIRMWARE=y BR2_PACKAGE_RPI_FIRMWARE_VARIANT_PI4=y BR2_PACKAGE_RPI_FIRMWARE_CONFIG_FILE="board/raspberrypi4/config_4.txt" BR2_PACKAGE_WPEWEBKIT=y BR2_TARGET_ROOTFS_EXT2=y BR2_TARGET_ROOTFS_EXT2_4=y BR2_TARGET_ROOTFS_EXT2_SIZE="120M" BR2_PACKAGE_HOST_DOSFSTOOLS=y BR2_PACKAGE_HOST_GENIMAGE=y BR2_PACKAGE_HOST_MTOOLS=y EOF % make O=wpewebkit-neon wpewebkit_neon_defconfig % make O=wpewebkit-neon BR2_JLEVEL=$(nproc) wpewebkit After a while, the build will fail with: [ 48%] Building CXX object Source/WebCore/CMakeFiles/WebCore.dir/__/__/WebCore/DerivedSources/unified-sources/UnifiedSource-cbdfe323-42.cpp.o In file included from platform/graphics/filters/FESpecularLighting.h:25, from svg/SVGFESpecularLightingElement.h:25, from ../../WebCore/DerivedSources/JSSVGFESpecularLightingElement.h:26, from ../../WebCore/DerivedSources/JSSVGFESpecularLightingElement.cpp:22, from ../../WebCore/DerivedSources/unified-sources/UnifiedSource-3a52ce78-119.cpp:5: platform/graphics/filters/FELighting.h:72:41: error: ‘LightingData’ does not name a type 72 | inline void platformApplyNeon(const LightingData&, const LightSource::PaintingData&); | ^~~~~~~~~~~~ make[4]: *** [Source/WebCore/CMakeFiles/WebCore.dir/build.make:5152: Source/WebCore/CMakeFiles/WebCore.dir/__/__/WebCore/DerivedSources/unified-sources/UnifiedSource-3a52ce78-119.cpp.o] Error 1 Moreover, it seems that nothing calls FELighting::platformApplyNeon() anymore, which means even the code got built it would not be used.