Bug 705454 – media-gfx/krita-4.2.8.2 USE=vc - In file included from.../work/krita-4.2.8.2/libs/pigment/compositeops/KoOptimizedCompositeOpFactory.cpp:20: /usr/include/Vc/avx/intrinsics.h:458:5: error: ‘_mm256_comlt_epu32’ was not declared in this scope; did you mean ‘

• Status: RESOLVED TEST-REQUEST
• Product: Gentoo Linux

[Description Sandi (Sandy) Vujaković 2020-01-14 23:27:36 UTC]

This has been going on for months now. Without the Vc USE flag, it successfully builds, but compilation fails when enabling the Vc USE flag.

Before somebody asks why I did not report this sooner, well... I had school things to tend to and hoped that this would resolve itself. Also, this made me (and still makes me) uneasy about reporting issues related to Vc: https://github.com/VcDevel/Vc/commit/6808742be78502ea68866e0a8c860cf1408a91ed

[Comment 1 Sandi (Sandy) Vujaković 2020-01-15 00:10:06 UTC]

Created attachment 603322 [details]
build.log

[Comment 2 Sandi (Sandy) Vujaković 2020-01-15 00:15:35 UTC]

Created attachment 603324 [details]
emerge --info

[Comment 3 Sandi (Sandy) Vujaković 2020-01-15 01:38:15 UTC]

I just rebuilt dev-libs/vc with the Gentoo default flags and there is no difference.

[Comment 4 Guillermo D. H. 2020-01-24 21:55:02 UTC]

I think thus is a bug in dev-libs/vc. Header Vc/avx/intrinsics.h contains this fragment:

#if defined(Vc_IMPL_XOP)
    Vc_AVX_TO_SSE_2_NEW(comlt_epu32)
    Vc_AVX_TO_SSE_2_NEW(comgt_epu32)
    Vc_AVX_TO_SSE_2_NEW(comlt_epu16)
    Vc_AVX_TO_SSE_2_NEW(comgt_epu16)
    static Vc_INTRINSIC m256i Vc_CONST cmplt_epu32(__m256i a, __m256i b) { return comlt_epu32(a, b); }
    static Vc_INTRINSIC m256i Vc_CONST cmpgt_epu32(__m256i a, __m256i b) { return comgt_epu32(a, b); }
    static Vc_INTRINSIC m256i Vc_CONST cmplt_epu16(__m256i a, __m256i b) { return comlt_epu16(a, b); }
    static Vc_INTRINSIC m256i Vc_CONST cmpgt_epu16(__m256i a, __m256i b) { return comgt_epu16(a, b); }
#else
[...]

which I suppose makes GCC generate implementations with XOP instructions for these functions, by calling magic builtin fuctions defined in <x86intrin.h>. And also contains two definitions of macro Vc_AVX_TO_SSE_2_NEW(), one that I suppose makes GCC generate implementations

[Comment 5 Guillermo D. H. 2020-01-24 22:00:51 UTC]

with AVX2 instructions, and one that doesn't. The former creates invalid function names if called from that fragment. That is, when both Vc_IMPL_XOP and Vc_IMPL_AVX2 are defined.

I suppose both are when -march=bdver4 is in CFLAGS.

[Comment 6 Andreas Sturmlechner 2020-02-13 22:36:40 UTC]

Adding vc maintainer then.

[Comment 7 Jonas Stein 2022-02-14 20:33:48 UTC]

please retest with media-gfx/krita-4.4.8-r1 and newer. 
Reopen if the bug is still there.