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Bug 749681 - media-libs/opencv-4.5.0[examples]: samples/cpp/digits_lenet.cpp:16:10: fatal error: opencv2/dnn.hpp: No such file or directory
Summary: media-libs/opencv-4.5.0[examples]: samples/cpp/digits_lenet.cpp:16:10: fatal ...
Alias: None
Product: Gentoo Linux
Classification: Unclassified
Component: Current packages (show other bugs)
Hardware: All Linux
: Normal normal (vote)
Assignee: Amy Liffey
Keywords: PullRequest
Depends on:
Blocks: 746596
  Show dependency tree
Reported: 2020-10-17 11:09 UTC by Kobboi
Modified: 2020-11-03 07:18 UTC (History)
4 users (show)

See Also:
Package list:
Runtime testing required: ---

build.log.gz (build.log.gz,70.00 KB, application/gzip)
2020-10-17 11:56 UTC, Kobboi

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Description Kobboi 2020-10-17 11:09:57 UTC

Reproducible: Always

 * Package:    media-libs/opencv-4.5.0
 * Repository: gentoo
 * Maintainer:
 * USE:        abi_x86_64 amd64 contrib cpu_flags_x86_popcnt cpu_flags_x86_sse cpu_flags_x86_sse2 cpu_flags_x86_sse3 cpu_flags_x86_sse4_1 cpu_flags_x86_sse4_2 cpu_flags_x86_ssse3 eigen elibc_glibc examples features2d ffmpeg gstreamer jpeg kernel_linux opencl opencvapps opengl openmp png python python_targets_python3_7 qt5 threads tiff userland_GNU vaapi
 * FEATURES:   compressdebug installsources network-sandbox preserve-libs sandbox splitdebug userpriv usersandbox
Comment 1 Sam James archtester Gentoo Infrastructure gentoo-dev Security 2020-10-17 11:24:11 UTC
Full build.log and emerge --info please.
Comment 2 Kobboi 2020-10-17 11:25:01 UTC
Trying a build with USE=-examples first.
Comment 3 Kobboi 2020-10-17 11:42:35 UTC
Compiles fine with USE=-examples
Comment 4 Kobboi 2020-10-17 11:56:39 UTC
Created attachment 666188 [details]
Comment 5 Sam James archtester Gentoo Infrastructure gentoo-dev Security 2020-10-17 11:57:46 UTC
--info too? thank you!
Comment 6 Ross Charles C. 2020-10-17 12:13:11 UTC
Does it work if you enable contribdnn and dnnsamples USE flag?
Comment 7 Kobboi 2020-10-17 14:42:31 UTC
(In reply to Ross Charles C. from comment #6)
> Does it work if you enable contribdnn and dnnsamples USE flag?

It does.
Comment 8 Larry the Git Cow gentoo-dev 2020-11-03 07:18:33 UTC
The bug has been closed via the following commit(s):

commit c92eaa6a7d93400503334e9c65df2b8e400ab90f
Author:     Ross Charles Campbell <>
AuthorDate: 2020-10-18 14:59:46 +0000
Commit:     Sam James <>
CommitDate: 2020-11-03 07:18:26 +0000

    media-libs/opencv: various fixes
     - Explicitly depends on virtual/lapacke to prevent its cmake build scripts from
    implicitly disabling lapack support when it can't find lapacke.h.
     - Link with cblas when sci-libs/lapack is supplimented as the default lapack
     - examples USE requires contribdnn USE to be enabled to prevent build failure.
    Package-Manager: Portage-3.0.8, Repoman-3.0.1
    Signed-off-by: Ross Charles Campbell <>
    Signed-off-by: Sam James <>

 .../opencv-4.5.0-link-with-cblas-for-lapack.patch      | 18 ++++++++++++++++++
 media-libs/opencv/opencv-4.5.0.ebuild                  |  8 +++++++-
 2 files changed, 25 insertions(+), 1 deletion(-)