gimp startup problem with 2.10.14-r1 and 2.10.18-r1. Takes excessive time while reading "Brushes My Paint" (as displayed in the splash screen) with 100% cpu. Took 46 minutes process time to launch. Same thing at next launch. strace shows it spends time reading each brush: Displays text like below, then waits 10 seconds, then goes to the next bush. Seems when gimp/libmypaint/gegl are compiled with gcc 8.3.0, 9.2.0-r4, 10.1.0. lstat("/usr/share/mypaint-data/1.0/brushes/classic/pen_prev.png", {st_mode=S_IFREG|0644, st_size=8554, ...}) = 0 openat(AT_FDCWD, "/usr/share/mypaint-data/1.0/brushes/classic/.hidden", O_RDONLY) = -1 ENOENT (Aucun fichier ou dossier de ce type) write(6, "\1\0\0\0\0\0\0\0", 8) = 8 lstat("/usr/share/mypaint-data/1.0/brushes/classic/pointy_ink.myb", {st_mode=S_IFREG|0644, st_size=6595, ...}) = 0 openat(AT_FDCWD, "/usr/share/mypaint-data/1.0/brushes/classic/pointy_ink.myb", O_RDONLY) = 11 fstat(11, {st_mode=S_IFREG|0644, st_size=6595, ...}) = 0 lstat("/usr/share/mypaint-data/1.0/brushes/classic/pointy_ink.myb", {st_mode=S_IFREG|0644, st_size=6595, ...}) = 0 read(11, "{\n \"comment\": \"MyPaint brush "..., 6595) = 6595 mmap(NULL, 85899345920, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f16cc000000 --- here waits for few seconds --- openat(AT_FDCWD, "/usr/share/mypaint-data/1.0/brushes/classic/pointy_ink_prev.png", O_RDONLY) = 12 fstat(12, {st_mode=S_IFREG|0644, st_size=9458, ...}) = 0 read(12, "\211PNG\r\n\32\n\0\0\0\rIHDR\0\0\0\200\0\0\0\200\10\2\0\0\0L\\\366"..., 65536) = 9458 read(12, "", 53248) = 0 stat("/home/jerome/.home/.local/share/mime//mime.cache", {st_mode=S_IFREG|0644, st_size=1140, ...}) = 0 stat("/usr/local/share/mime//mime.cache", 0x7ffd43ea3500) = -1 ENOENT (Aucun fichier ou dossier de ce type) stat("/usr/local/share/mime//globs", 0x7ffd43ea3500) = -1 ENOENT (Aucun fichier ou dossier de ce type) stat("/usr/local/share/mime//magic", 0x7ffd43ea3500) = -1 ENOENT (Aucun fichier ou dossier de ce type) stat("/usr/share/mime//mime.cache", {st_mode=S_IFREG|0644, st_size=184908, ...}) = 0 close(12) = 0 munmap(0x7f16cc000000, 85899345920) = 0 close(11) = 0 lstat("/usr/share/mypaint-data/1.0/brushes/classic/pointy_ink_prev.png", {st_mode=S_IFREG|0644, st_size=9458, ...}) = 0 openat(AT_FDCWD, "/usr/share/mypaint-data/1.0/brushes/classic/.hidden", O_RDONLY) = -1 ENOENT (Aucun fichier ou dossier de ce type) write(6, "\1\0\0\0\0\0\0\0", 8) = 8 lstat("/usr/share/mypaint-data/1.0/brushes/classic/puantilism2.myb", {st_mode=S_IFREG|0644, st_size=9422, ...}) = 0 openat(AT_FDCWD, "/usr/share/mypaint-data/1.0/brushes/classic/puantilism2.myb", O_RDONLY) = 11 fstat(11, {st_mode=S_IFREG|0644, st_size=9422, ...}) = 0 lstat("/usr/share/mypaint-data/1.0/brushes/classic/puantilism2.myb", {st_mode=S_IFREG|0644, st_size=9422, ...}) = 0 read(11, "{\n \"comment\": \"MyPaint brush "..., 9422) = 9422 mmap(NULL, 85899345920, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f16cc000000 --- here waits for few seconds --- Reproducible: Always Portage 2.3.99 (python 3.7.7-final-0, default/linux/amd64/17.1/desktop/plasma, gcc-8.4.0, glibc-2.30-r8, 5.6.13-gentoo-x86_64 x86_64) ================================================================= System uname: Linux-5.6.13-gentoo-x86_64-x86_64-AMD_Ryzen_9_3950X_16-Core_Processor-with-gentoo-2.6 KiB Mem: 131899012 total, 116300160 free KiB Swap: 0 total, 0 free Timestamp of repository gentoo: Sun, 17 May 2020 23:00:01 +0000 Head commit of repository gentoo: 3af5979293af1ac6340e5199b819f4e1be1d5d7d Head commit of repository science: f3a538b68e80b3fc42af81717f48a5cbfb283f45 sh bash 5.0_p17 ld GNU ld (Gentoo 2.33.1 p2) 2.33.1 app-shells/bash: 5.0_p17::gentoo dev-java/java-config: 2.2.0-r4::gentoo dev-lang/perl: 5.30.1::gentoo dev-lang/python: 2.7.18::gentoo, 3.6.10-r2::gentoo, 3.7.7-r2::gentoo, 3.8.2-r2::gentoo dev-util/cmake: 3.16.5::gentoo sys-apps/baselayout: 2.6-r1::gentoo sys-apps/openrc: 0.42.1::gentoo sys-apps/sandbox: 2.13::gentoo sys-devel/autoconf: 2.13-r1::gentoo, 2.69-r4::gentoo sys-devel/automake: 1.11.6-r3::gentoo, 1.16.1-r1::gentoo sys-devel/binutils: 2.33.1-r1::gentoo sys-devel/gcc: 8.4.0::gentoo, 9.2.0-r4::gentoo, 10.1.0::gentoo sys-devel/gcc-config: 2.2.1::gentoo sys-devel/libtool: 2.4.6-r6::gentoo sys-devel/make: 4.2.1-r4::gentoo sys-kernel/linux-headers: 5.6::gentoo (virtual/os-headers) sys-libs/glibc: 2.30-r8::gentoo Repositories: gentoo location: /tmp/repos/gentoo sync-type: rsync sync-uri: rsync://rsync.gentoo.org/gentoo-portage priority: -1000 sync-rsync-verify-max-age: 24 sync-rsync-verify-metamanifest: yes sync-rsync-verify-jobs: 1 sync-rsync-extra-opts: --quiet --times --omit-dir-times --omit-link-times localrepo location: /var/db/repos/localrepo masters: gentoo science location: /var/db/repos/science sync-type: git sync-uri: git://git.gentoo.org/proj/sci.git masters: gentoo x-portage location: /usr/local/portage masters: gentoo priority: 0 palemoon location: /var/lib/layman/palemoon masters: gentoo priority: 50 pf4public location: /var/lib/layman/pf4public masters: gentoo priority: 50 stuff location: /var/lib/layman/stuff masters: gentoo priority: 50 ACCEPT_KEYWORDS="amd64" ACCEPT_LICENSE="@FREE" CBUILD="x86_64-pc-linux-gnu" CFLAGS="-O2 -pipe -march=native" CHOST="x86_64-pc-linux-gnu" CONFIG_PROTECT="/etc /usr/lib64/libreoffice/program/sofficerc /usr/share/config /usr/share/gnupg/qualified.txt" CONFIG_PROTECT_MASK="/etc/ca-certificates.conf /etc/dconf /etc/env.d /etc/fonts/fonts.conf /etc/gconf /etc/gentoo-release /etc/revdep-rebuild /etc/sandbox.d /etc/terminfo /etc/texmf/language.dat.d /etc/texmf/language.def.d /etc/texmf/updmap.d /etc/texmf/web2c" CXXFLAGS="-O2 -pipe -march=native" DISTDIR="/tmp/var/cache/distfiles" EMERGE_DEFAULT_OPTS="--with-bdeps=y --keep-going --jobs 20 --load-average 30" ENV_UNSET="DBUS_SESSION_BUS_ADDRESS DISPLAY GOBIN PERL5LIB PERL5OPT PERLPREFIX PERL_CORE PERL_MB_OPT PERL_MM_OPT XAUTHORITY XDG_CACHE_HOME XDG_CONFIG_HOME XDG_DATA_HOME XDG_RUNTIME_DIR" FCFLAGS="-O2 -pipe -march=native" FEATURES="assume-digests binpkg-docompress binpkg-dostrip binpkg-logs config-protect-if-modified distlocks ebuild-locks fixlafiles ipc-sandbox merge-sync multilib-strict network-sandbox news parallel-fetch pid-sandbox preserve-libs protect-owned qa-unresolved-soname-deps sandbox sfperms strict unknown-features-warn unmerge-logs unmerge-orphans userfetch userpriv usersandbox usersync xattr" FFLAGS="-O2 -pipe -march=native" GENTOO_MIRRORS="ftp://ftp.rnl.tecnico.ulisboa.pt/pub/gentoo/gentoo-distfiles/ ftp://gentoo.mirrors.ovh.net/gentoo-distfiles/ ftp://ftp.halifax.rwth-aachen.de/gentoo/ ftp://ftp.wh2.tu-dresden.de/pub/mirrors/gentoo http://distfiles.gentoo.org http://www.ibiblio.org/pub/Linux/distributions/gentoo" LANG="fr_FR.utf8" LDFLAGS="-Wl,-O1 -Wl,--as-needed" MAKEOPTS="-j32" PKGDIR="/var/cache/binpkgs" PORTAGE_CONFIGROOT="/" PORTAGE_RSYNC_EXTRA_OPTS="--quiet --times --omit-dir-times --omit-link-times" PORTAGE_RSYNC_OPTS="--recursive --links --safe-links --perms --times --omit-dir-times --compress --force --whole-file --delete --stats --human-readable --timeout=180 --exclude=/distfiles --exclude=/local --exclude=/packages --exclude=/.git" PORTAGE_TMPDIR="/tmp/var/tmp" USE="X a52 aac acl acpi activities alsa amd64 berkdb branding bzip2 cairo cdda cdr cdrom cli crypt cuda cups dbus declarative dri dropbox dts dvd dvdr elogind emboss encode exif ffmpeg flac fortran gdbm gif gmp gpm gtk iconv icu ipv6 jpeg kde kipi lcms ldap libnotify libtirpc mad mp3 mp4 mpeg multilib ncurses nls nptl ogg opengl openmp opus pam pango pcre pdf phonon plasma png policykit ppds qml qt5 readline sdl seccomp spell split-usr ssl startup-notification svg tcpd tiff truetype udev udisks unicode upower usb vim-syntax vorbis widgets wxwidgets x264 xattr xcb xml xv xvid zlib" ABI_X86="64" ADA_TARGET="gnat_2018" ALSA_CARDS="ali5451 als4000 atiixp atiixp-modem bt87x ca0106 cmipci emu10k1x ens1370 ens1371 es1938 es1968 fm801 hda-intel intel8x0 intel8x0m maestro3 trident usb-audio via82xx via82xx-modem ymfpci" APACHE2_MODULES="authn_core authz_core socache_shmcb unixd actions alias auth_basic authn_alias authn_anon authn_dbm authn_default authn_file authz_dbm authz_default authz_groupfile authz_host authz_owner authz_user autoindex cache cgi cgid dav dav_fs dav_lock deflate dir disk_cache env expires ext_filter file_cache filter headers include info log_config logio mem_cache mime mime_magic negotiation rewrite setenvif speling status unique_id userdir usertrack vhost_alias" CALLIGRA_FEATURES="karbon sheets stage words" COLLECTD_PLUGINS="df interface irq load memory rrdtool swap syslog" CPU_FLAGS_X86="aes avx avx2 f16c fma3 mmx mmxext pclmul popcnt sha sse sse2 sse3 sse4_1 sse4_2 sse4a ssse3" ELIBC="glibc" GPSD_PROTOCOLS="ashtech aivdm earthmate evermore fv18 garmin garmintxt gpsclock greis isync itrax mtk3301 nmea ntrip navcom oceanserver oldstyle oncore rtcm104v2 rtcm104v3 sirf skytraq superstar2 timing tsip tripmate tnt ublox ubx" GRUB_PLATFORMS="efi-64" INPUT_DEVICES="libinput" KERNEL="linux" L10N="fr fr-FR" LCD_DEVICES="bayrad cfontz cfontz633 glk hd44780 lb216 lcdm001 mtxorb ncurses text" LIBREOFFICE_EXTENSIONS="presenter-console presenter-minimizer" OFFICE_IMPLEMENTATION="libreoffice" PHP_TARGETS="php7-2" POSTGRES_TARGETS="postgres10 postgres11" PYTHON_SINGLE_TARGET="python3_7" PYTHON_TARGETS="python2_7 python3_7" RUBY_TARGETS="ruby24 ruby25" USERLAND="GNU" VIDEO_CARDS="fbdev vesa dummy nvidia" XTABLES_ADDONS="quota2 psd pknock lscan length2 ipv4options ipset ipp2p iface geoip fuzzy condition tee tarpit sysrq steal rawnat logmark ipmark dhcpmac delude chaos account" Unset: CC, CPPFLAGS, CTARGET, CXX, INSTALL_MASK, LC_ALL, LINGUAS, PORTAGE_BINHOST, PORTAGE_BUNZIP2_COMMAND, PORTAGE_COMPRESS, PORTAGE_COMPRESS_FLAGS
I can't confirm myself 100% but two users reported the patch in bug #723480 (for json-c) fixed this. https://forums.gentoo.org/viewtopic-t-1113276.html
I can confirm the patch fixes the problem. patch: https://github.com/json-c/json-c/commit/519dfe1591d85432986f9762d41d1a883198c157.patch saved into /etc/portage/patches/dev-libs/json-0.14-r2/bug_723526.patch re-emerged json-c. Problem solved
