I suspect the same problem exists for dev-qt/qtgui-5.12.3-r1. From the build.log /storage/strogdon/gentoo-rap/var/tmp/portage/dev-qt/qtgui-5.12.5/work/qtbase-everywhere-src-5.12.5/src/gui/qvkgen_wrapper.sh vulkan/vk.xml /storage/strogdon/gentoo-rap/var/tmp/portage/dev-qt/qtgui-5.12.5/work/qtbase-everywhere-src-5.12.5/header.LGPL vulkan/qvulkanfunctions /storage/strogdon/gentoo-rap/var/tmp/portage/dev-qt/qtgui-5.12.5/work/qtbase-everywhere-src-5.12.5/bin/qvkgen: error while loading shared libraries: libQt5Core.so.5: cannot open shared object file: No such file or directory ldd ~/var/tmp/portage/dev-qt/qtgui-5.12.5/work/qtbase-everywhere-src-5.12.5/bin/qvkgen linux-vdso.so.1 (0x00007ffe3e3e6000) libQt5Core.so.5 => not found libc.so.6 => /storage/strogdon/gentoo-rap/lib64/libc.so.6 (0x00007f2c05520000) /storage/strogdon/gentoo-rap/lib64/ld-linux-x86-64.so.2 (0x00007f2c05afb000) However, qtcore-5.12.5-r1 had been installed: ls -al ~/usr/lib/libQt5Core* -rw-r--r-- 1 strogdon math 1232 Nov 2 16:39 /storage/strogdon/gentoo-rap/usr/lib/libQt5Core.prl lrwxrwxrwx 1 strogdon math 20 Nov 2 16:39 /storage/strogdon/gentoo-rap/usr/lib/libQt5Core.so -> libQt5Core.so.5.12.5 lrwxrwxrwx 1 strogdon math 20 Nov 2 16:39 /storage/strogdon/gentoo-rap/usr/lib/libQt5Core.so.5 -> libQt5Core.so.5.12.5 lrwxrwxrwx 1 strogdon math 20 Nov 2 16:39 /storage/strogdon/gentoo-rap/usr/lib/libQt5Core.so.5.12 -> libQt5Core.so.5.12.5 -rwxr-xr-x 1 strogdon math 71699952 Nov 2 16:39 /storage/strogdon/gentoo-rap/usr/lib/libQt5Core.so.5.12.5 I believe the real issue is with qtcore. The following change when applied to qtcore will allow qtgui to build --- /src/corelib/global/minimum-linux_p.h.orig 2019-11-01 22:01:13.800781194 -0500 +++ /src/corelib/global/minimum-linux_p.h 2019-11-01 22:04:33.638063279 -0500 @@ -78,27 +78,13 @@ * - statx 4.11 QT_CONFIG(statx) */ -#if QT_CONFIG(statx) && !QT_CONFIG(glibc) // if using glibc, the statx() function in sysdeps/unix/sysv/linux/statx.c // falls back to stat() for us. // (Using QT_CONFIG(glibc) instead of __GLIBC__ because the macros aren't // defined in assembler mode) -# define MINLINUX_MAJOR 4 -# define MINLINUX_MINOR 11 -# define MINLINUX_PATCH 0 -#elif QT_CONFIG(getentropy) -# define MINLINUX_MAJOR 3 -# define MINLINUX_MINOR 17 -# define MINLINUX_PATCH 0 -#elif QT_CONFIG(renameat2) -# define MINLINUX_MAJOR 3 -# define MINLINUX_MINOR 16 -# define MINLINUX_PATCH 0 -#else # define MINLINUX_MAJOR 2 # define MINLINUX_MINOR 6 # define MINLINUX_PATCH 28 -#endif #define MINIMUM_LINUX_VERSION QT_VERSION_CHECK(MINLINUX_MAJOR, MINLINUX_MINOR, MINLINUX_PATCH) I have no idea why this works nor whether this is correct, only that it allows qtgui to build. There have been similar resolved bugs but not in Prefix (See https://bugs.gentoo.org/show_bug.cgi?id=669994 and https://bugs.gentoo.org/show_bug.cgi?id=672856) which seem to point to the use of this patch https://bugs.gentoo.org/attachment.cgi?id=557978
*** This bug has been marked as a duplicate of bug 669994 ***
