Hello,

Since commit bec45e6ddb0fd8b8feff3c0147936e4d8f41208d, 'x265' fails to
build on i686:

--8<---------------cut here---------------start------------->8---
[ 29%] Building ASM_NASM object common/CMakeFiles/common.dir/x86/ssd-a.asm.o
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/x86/ssd-a.asm:827: error: invalid combination of opcode and operands
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/x86/ssd-a.asm:119: ... from macro `SSD_ONE' defined here
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/../common/x86/x86inc.asm:1373: ... from macro `movq' defined here
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/../common/x86/x86inc.asm:1225: ... from macro `RUN_AVX_INSTR' defined here
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/x86/ssd-a.asm:828: error: invalid combination of opcode and operands
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/x86/ssd-a.asm:119: ... from macro `SSD_ONE' defined here
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/../common/x86/x86inc.asm:1373: ... from macro `movq' defined here
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/../common/x86/x86inc.asm:1225: ... from macro `RUN_AVX_INSTR' defined here
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/x86/ssd-a.asm:829: error: invalid combination of opcode and operands
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/x86/ssd-a.asm:119: ... from macro `SSD_ONE' defined here
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/../common/x86/x86inc.asm:1373: ... from macro `movq' defined here
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/../common/x86/x86inc.asm:1225: ... from macro `RUN_AVX_INSTR' defined here
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/x86/ssd-a.asm:832: error: invalid combination of opcode and operands
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/x86/ssd-a.asm:119: ... from macro `SSD_ONE' defined here
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/../common/x86/x86inc.asm:1373: ... from macro `movq' defined here
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/../common/x86/x86inc.asm:1225: ... from macro `RUN_AVX_INSTR' defined here
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/x86/ssd-a.asm:833: error: invalid combination of opcode and operands
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/x86/ssd-a.asm:119: ... from macro `SSD_ONE' defined here
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/../common/x86/x86inc.asm:1373: ... from macro `movq' defined here
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/../common/x86/x86inc.asm:1225: ... from macro `RUN_AVX_INSTR' defined here
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/x86/ssd-a.asm:843: error: invalid combination of opcode and operands
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/x86/ssd-a.asm:262: ... from macro `SSD_ONE_SS_32' defined here
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/../common/x86/x86inc.asm:1373: ... from macro `movq' defined here
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/../common/x86/x86inc.asm:1225: ... from macro `RUN_AVX_INSTR' defined here
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/x86/ssd-a.asm:844: error: invalid combination of opcode and operands
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/x86/ssd-a.asm:348: ... from macro `SSD_ONE_SS_64' defined here
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/../common/x86/x86inc.asm:1373: ... from macro `movq' defined here
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/../common/x86/x86inc.asm:1225: ... from macro `RUN_AVX_INSTR' defined here
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/x86/ssd-a.asm:853: error: invalid combination of opcode and operands
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/x86/ssd-a.asm:130: ... from macro `SSD_ONE' defined here
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/../common/x86/x86inc.asm:1373: ... from macro `movq' defined here
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/../common/x86/x86inc.asm:1225: ... from macro `RUN_AVX_INSTR' defined here
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/x86/ssd-a.asm:854: error: invalid combination of opcode and operands
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/x86/ssd-a.asm:130: ... from macro `SSD_ONE' defined here
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/../common/x86/x86inc.asm:1373: ... from macro `movq' defined here
/tmp/guix-build-x265-3.3.drv-0/x265_3.3/source/common/../common/x86/x86inc.asm:1225: ... from macro `RUN_AVX_INSTR' defined here
make[2]: *** [common/CMakeFiles/common.dir/build.make:78: common/CMakeFiles/common.dir/x86/ssd-a.asm.o] Error 1
--8<---------------cut here---------------end--------------->8---