Right now, doxygen provides two ineffective USE flags: 'dot' and 'latex'. These flags only pull in runtime dependencies, while not affecting the doxygen code at all. Thus, for users having either graphviz or respective latex parts installed, they only force needless USE change and rebuild of doxygen. I think that the flags should be removed (or possibly transformed into GLEP-62 IUSE_RUNTIME at some point) and the packages should depend on the required packages directly instead. Sometimes, this is already a case because of the output format choice. Namely, dependency on doxygen[dot] does not enforce the DOT_IMAGE_FORMAT. Effectively, the package should instead depend on e.g.: app-doc/doxygen media-gfx/graphviz[svg]
IIRC, the original request (and meaning) of the dot USE flag for doxygen itself was to build its own manual during install. Building the PDF doxygen manual requires both graphviz and a latex tool to complete "make refman". Building the HTML doxygen manual would only need graphviz itself. SVG graphics in the doxygen output in general should be optional (I think it defaults to .png images, but .svg allows interactive zoom/pan for large graphs now). PNG is probably a better default for install.
The bug has been referenced in the following commit(s): https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=0f55d7b4be1b2a323f1d0591cb988db9c47402e9 commit 0f55d7b4be1b2a323f1d0591cb988db9c47402e9 Author: Matthias Maier <tamiko@gentoo.org> AuthorDate: 2020-03-01 18:31:02 +0000 Commit: Matthias Maier <tamiko@gentoo.org> CommitDate: 2020-03-01 18:35:47 +0000 app-doc/doxygen: remove latex use flag Bug: https://bugs.gentoo.org/430914 Closes: https://bugs.gentoo.org/704382 Package-Manager: Portage-2.3.89, Repoman-2.3.20 Signed-off-by: Matthias Maier <tamiko@gentoo.org> app-doc/doxygen/doxygen-1.8.17.ebuild | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=463d6d1b9e83b541e9c8e63ef0043a07581cb44c commit 463d6d1b9e83b541e9c8e63ef0043a07581cb44c Author: Matthias Maier <tamiko@gentoo.org> AuthorDate: 2020-03-01 18:29:13 +0000 Commit: Matthias Maier <tamiko@gentoo.org> CommitDate: 2020-03-01 18:35:44 +0000 dev-python/breathe: remove app-doc/doxygen[latex] dependency Bug: https://bugs.gentoo.org/430914 Bug: https://bugs.gentoo.org/709316 Package-Manager: Portage-2.3.89, Repoman-2.3.20 Signed-off-by: Matthias Maier <tamiko@gentoo.org> dev-python/breathe/breathe-4.6.0.ebuild | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=b3c6c8ba19c0e81dcf147db9366f2b45676677c1 commit b3c6c8ba19c0e81dcf147db9366f2b45676677c1 Author: Matthias Maier <tamiko@gentoo.org> AuthorDate: 2020-03-01 18:26:26 +0000 Commit: Matthias Maier <tamiko@gentoo.org> CommitDate: 2020-03-01 18:35:40 +0000 media-gfx/blender: remove app-doc/doxygen[latex] dependency Bug: https://bugs.gentoo.org/430914 Bug: https://bugs.gentoo.org/709316 Package-Manager: Portage-2.3.89, Repoman-2.3.20 Signed-off-by: Matthias Maier <tamiko@gentoo.org> media-gfx/blender/blender-2.79b-r2.ebuild | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=65af2a26ee33c814733a2982a0bd359c99c4ea54 commit 65af2a26ee33c814733a2982a0bd359c99c4ea54 Author: Matthias Maier <tamiko@gentoo.org> AuthorDate: 2020-03-01 18:24:30 +0000 Commit: Matthias Maier <tamiko@gentoo.org> CommitDate: 2020-03-01 18:35:37 +0000 sci-physics/rivet: remove app-doc/doxygen[latex] dependency Bug: https://bugs.gentoo.org/430914 Bug: https://bugs.gentoo.org/709316 Package-Manager: Portage-2.3.89, Repoman-2.3.20 Signed-off-by: Matthias Maier <tamiko@gentoo.org> sci-physics/rivet/rivet-2.6.0-r2.ebuild | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=2f524825d0a3fed7a646379638310a05a946dba1 commit 2f524825d0a3fed7a646379638310a05a946dba1 Author: Matthias Maier <tamiko@gentoo.org> AuthorDate: 2020-03-01 18:23:02 +0000 Commit: Matthias Maier <tamiko@gentoo.org> CommitDate: 2020-03-01 18:35:34 +0000 sci-physics/lhapdf: remove app-doc/doxygen[latex] dependency Bug: https://bugs.gentoo.org/430914 Bug: https://bugs.gentoo.org/709316 Package-Manager: Portage-2.3.89, Repoman-2.3.20 Signed-off-by: Matthias Maier <tamiko@gentoo.org> sci-physics/lhapdf/lhapdf-5.9.1.ebuild | 11 +++++++++-- sci-physics/lhapdf/lhapdf-6.2.3.ebuild | 10 +++++++++- 2 files changed, 18 insertions(+), 3 deletions(-) https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=c5d9331d2d771cf05587e3d18dba8580feaf342b commit c5d9331d2d771cf05587e3d18dba8580feaf342b Author: Matthias Maier <tamiko@gentoo.org> AuthorDate: 2020-03-01 18:21:58 +0000 Commit: Matthias Maier <tamiko@gentoo.org> CommitDate: 2020-03-01 18:35:30 +0000 sci-physics/clhep: remove app-doc/doxygen[latex] dependency Bug: https://bugs.gentoo.org/430914 Bug: https://bugs.gentoo.org/709316 Package-Manager: Portage-2.3.89, Repoman-2.3.20 Signed-off-by: Matthias Maier <tamiko@gentoo.org> sci-physics/clhep/clhep-2.4.0.4.ebuild | 13 +++++++++++-- sci-physics/clhep/clhep-2.4.1.2.ebuild | 13 +++++++++++-- 2 files changed, 22 insertions(+), 4 deletions(-) https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=24ec5bf3e8e9bfa2a4adaec9bc7359e6e32e5ec0 commit 24ec5bf3e8e9bfa2a4adaec9bc7359e6e32e5ec0 Author: Matthias Maier <tamiko@gentoo.org> AuthorDate: 2020-03-01 18:20:42 +0000 Commit: Matthias Maier <tamiko@gentoo.org> CommitDate: 2020-03-01 18:35:27 +0000 sci-libs/givaro: remove app-doc/doxygen[latex] dependency Bug: https://bugs.gentoo.org/430914 Bug: https://bugs.gentoo.org/709316 Package-Manager: Portage-2.3.89, Repoman-2.3.20 Signed-off-by: Matthias Maier <tamiko@gentoo.org> sci-libs/givaro/givaro-4.1.1.ebuild | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=3726e701a2e91b547c95127e055a4fbcb7579308 commit 3726e701a2e91b547c95127e055a4fbcb7579308 Author: Matthias Maier <tamiko@gentoo.org> AuthorDate: 2020-03-01 18:19:27 +0000 Commit: Matthias Maier <tamiko@gentoo.org> CommitDate: 2020-03-01 18:35:24 +0000 media-libs/partio: remove app-doc/doxygen[latex] dependency Bug: https://bugs.gentoo.org/430914 Bug: https://bugs.gentoo.org/709316 Package-Manager: Portage-2.3.89, Repoman-2.3.20 Signed-off-by: Matthias Maier <tamiko@gentoo.org> media-libs/partio/partio-1.1.0_p20170829.ebuild | 9 ++++++++- media-libs/partio/partio-1.5.4.ebuild | 9 ++++++++- media-libs/partio/partio-9999.ebuild | 9 ++++++++- 3 files changed, 24 insertions(+), 3 deletions(-) https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=b858d26684a92c5028bb55a2d89870b67c62046a commit b858d26684a92c5028bb55a2d89870b67c62046a Author: Matthias Maier <tamiko@gentoo.org> AuthorDate: 2020-03-01 18:18:04 +0000 Commit: Matthias Maier <tamiko@gentoo.org> CommitDate: 2020-03-01 18:35:21 +0000 media-libs/openimageio: remove app-doc/doxygen[latex] dependency Bug: https://bugs.gentoo.org/430914 Bug: https://bugs.gentoo.org/709316 Package-Manager: Portage-2.3.89, Repoman-2.3.20 Signed-off-by: Matthias Maier <tamiko@gentoo.org> media-libs/openimageio/openimageio-1.8.17-r2.ebuild | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=37cc5017352c2c76719e6f444d6145e409f4cdae commit 37cc5017352c2c76719e6f444d6145e409f4cdae Author: Matthias Maier <tamiko@gentoo.org> AuthorDate: 2020-03-01 18:16:27 +0000 Commit: Matthias Maier <tamiko@gentoo.org> CommitDate: 2020-03-01 18:35:17 +0000 media-gfx/openvdb: remove app-doc/doxygen[latex] dependency Bug: https://bugs.gentoo.org/430914 Bug: https://bugs.gentoo.org/709316 Package-Manager: Portage-2.3.89, Repoman-2.3.20 Signed-off-by: Matthias Maier <tamiko@gentoo.org> media-gfx/openvdb/openvdb-4.0.2-r3.ebuild | 9 ++++++++- media-gfx/openvdb/openvdb-5.2.0-r1.ebuild | 9 ++++++++- 2 files changed, 16 insertions(+), 2 deletions(-) https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=9a1b8ea907ba4ea540505f6fcc70831f11722d4c commit 9a1b8ea907ba4ea540505f6fcc70831f11722d4c Author: Matthias Maier <tamiko@gentoo.org> AuthorDate: 2020-03-01 18:07:37 +0000 Commit: Matthias Maier <tamiko@gentoo.org> CommitDate: 2020-03-01 18:35:14 +0000 dev-cpp/eigen: remove app-doc/doxygen[latex] dependency Bug: https://bugs.gentoo.org/430914 Bug: https://bugs.gentoo.org/709316 Package-Manager: Portage-2.3.89, Repoman-2.3.20 Signed-off-by: Matthias Maier <tamiko@gentoo.org> dev-cpp/eigen/eigen-3.3.7.ebuild | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-)
While we have removed all dependencies on app-doc/doxygen[latex], there is still a noticeable number of packages depending on app-doc/doxygen[dot].
The bug has been referenced in the following commit(s): https://gitweb.gentoo.org/repo/proj/guru.git/commit/?id=ad8a3e1457ab3a8a77d3d20ecc215ac41e59a22e commit ad8a3e1457ab3a8a77d3d20ecc215ac41e59a22e Author: Lucio Sauer <watermanpaint@posteo.net> AuthorDate: 2023-09-12 15:19:39 +0000 Commit: Lucio Sauer <watermanpaint@posteo.net> CommitDate: 2023-09-12 20:33:08 +0000 games-engines/easyrpg-player: remove app-doc/doxygen[dot] dependency Bug: https://bugs.gentoo.org/430914 Signed-off-by: Lucio Sauer <watermanpaint@posteo.net> games-engines/easyrpg-player/easyrpg-player-0.8.ebuild | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) https://gitweb.gentoo.org/repo/proj/guru.git/commit/?id=431d01c5b2acace232c38b43761cbb29e6c932b6 commit 431d01c5b2acace232c38b43761cbb29e6c932b6 Author: Lucio Sauer <watermanpaint@posteo.net> AuthorDate: 2023-09-12 15:17:58 +0000 Commit: Lucio Sauer <watermanpaint@posteo.net> CommitDate: 2023-09-12 20:33:04 +0000 dev-games/liblcf: remove app-doc/doxygen[dot] dependency Bug: https://bugs.gentoo.org/430914 Signed-off-by: Lucio Sauer <watermanpaint@posteo.net> dev-games/liblcf/liblcf-0.8.ebuild | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)