Safe way to move from zlib to zlib-ng with compat?

Message

logrusx · Post by **logrusx** » Wed Jan 07, 2026 6:29 pm

Hu wrote:Currently, that version of net-misc/openssh should be compatible. However, if you installed it before net-*/*: update for virtual/zlib, then yours might not be. Does emerge --oneshot net-misc/openssh remove it from the output? A similar situation applies to dev-libs/libxml2.

This replay is crucial for understanding the issue. Following the link one should notice dependencies on sys-libs/zlib were replaced by dependencies virtual/zlib.

Finding all packages that directly depend on sys-libz/zlib and emerge --oneshot them should untie them from sys-libs/zlib and solve the issue. Of course some of them are already recompiled after the change but to figure out which ones specifically you need to recompile is not a trivial job. Maybe grepping /var/db/pkg but I'm not that familiar enough with its structure to provide exact solution.

EDIT: The statement in tiny font above is incorrect. Emerge would not have reported those packages so the list is complete and exhaustive.

EDIT:
My workflow:

emerge -pvc sys-libs/zlib
emerge --deselect some stuff
emerge -1 <the above list of packages>
enable compat on sys-libs/zlib-ng
enable compat on sys-libs/minizip-ng
emerge -1auvDU --changed-deps @world sys-libs/zlib-ng minizip-ng virtual/minizip virtual/zlib

virtual/{minizip,zlib} were the ones for which packages were conflicting, that's why I included them on the command line. At the end I'm not sure I should have.

For you it might be slightly different.

This pulled in a bit over 370 packages, ~320 of which - binary.

After some more deselecting, I managed to avoid building a few big packages like nodejs and pull in the binary ones. All the packages I deselected are ones I rarely or occasionally need. It may be different for you.

Best Regards,
Georgi

Post by **sam_** » Wed Jan 07, 2026 7:31 pm

ScottESanDiego wrote:
sam_ wrote:Similarly, does emerge --changed-deps -a -uvDU @world sys-libs/zlib-ng work?
No, that didn't work.

I find that very surprising if the OpenSSH trick worked. Do you have the output still?

Perfect Gentleman · Post by **Perfect Gentleman** » Thu Jan 08, 2026 12:20 am

CaptainBlood wrote:Perfect Gentleman doesn't seems to have any of those problematic packages installed...
Lucky chap

Thks 4 ur attention, interest & support.

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~ $ qlist -Iv z*-ng
app-text/goldendict-ng-9999-r1
sys-libs/minizip-ng-4.0.10-r1
sys-libs/zlib-ng-2.3.2

ScottESanDiego · Post by **ScottESanDiego** » Thu Jan 08, 2026 12:28 am

sam_ wrote:
ScottESanDiego wrote:
sam_ wrote:Similarly, does emerge --changed-deps -a -uvDU @world sys-libs/zlib-ng work?
No, that didn't work.
I find that very surprising if the OpenSSH trick worked. Do you have the output still?

I don't. Looks like it's past the back of the scrollback buffer.

My exact emerge line was (from shell command history): emerge --update --changed-use --newuse --with-bdeps=y --deep --tree --ask @world sys-libs/zlib-ng

That gave me the identical behavior (aka blocked by zlib) as w/o `--changed-use` run of `emerge -a -uvDU @world sys-libs/zlib-ng` that I posted at the top of this thread.

logrusx · Post by **logrusx** » Thu Jan 08, 2026 5:40 am

ScottESanDiego wrote: I don't. Looks like it's past the back of the scrollback buffer.

My exact emerge line was (from shell command history): emerge --update --changed-use --newuse --with-bdeps=y --deep --tree --ask @world sys-libs/zlib-ng

That gave me the identical behavior (aka blocked by zlib) as w/o `--changed-use` run of `emerge -a -uvDU @world sys-libs/zlib-ng` that I posted at the top of this thread.

In the end, how did you solve it?

Best Regards,
Georgi

trubicoid · Post by **trubicoid** » Thu Jan 08, 2026 3:18 pm

What I did is to enable compat for zlib-ng and

Code: Select all

emerge --oneshot zlib-ng

This seems to put the libraries correctly, so the system should stay un-borken:

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$ ls -l /usr/lib64/libz.*
lrwxrwxrwx 1 root root      9 Jan  8 15:23 /usr/lib64/libz.so -> libz.so.1
lrwxrwxrwx 1 root root     21 Jan  8 15:23 /usr/lib64/libz.so.1 -> libz.so.1.3.1.zlib-ng
-rwxr-xr-x 1 root root 136456 Jan  8 15:23 /usr/lib64/libz.so.1.3.1.zlib-ng

However, the subsequent update wanted to pull virtual/zlib, which pulls sys-lib/zlib again! I think, it is because of the static-libs, zlib-ng does not have them, right?

Anyway, I found that my elfutils had static-libs for some obsolete reason (prelink) and removing it solved the problem.

ScottESanDiego · Post by **ScottESanDiego** » Thu Jan 08, 2026 3:58 pm

logrusx wrote:
ScottESanDiego wrote: I don't. Looks like it's past the back of the scrollback buffer.

My exact emerge line was (from shell command history): emerge --update --changed-use --newuse --with-bdeps=y --deep --tree --ask @world sys-libs/zlib-ng

That gave me the identical behavior (aka blocked by zlib) as w/o `--changed-use` run of `emerge -a -uvDU @world sys-libs/zlib-ng` that I posted at the top of this thread.
In the end, how did you solve it?

Best Regards,
Georgi

What worked for me was re-emerging the two packages that hadn't been built since the virtual/zlib change, THEN installing zlib-ng.

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emerge --oneshot dev-libs/libxml2 net-misc/openssh
emerge --ask sys-libs/zlib-ng

CaptainBlood · Post by **CaptainBlood** » Thu Jan 08, 2026 8:14 pm

trubicoid wrote:However, the subsequent update wanted to pull virtual/zlib, which pulls sys-lib/zlib again! I think, it is because of the static-libs, zlib-ng does not have them, right?

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[I] sys-libs/zlib-ng
     Available versions:  2.2.5^t 2.2.5-r1^t 2.3.2^t {compat static-libs test ABI_MIPS="n32 n64 o32" ABI_S390="32 64" ABI_X86="32 64 x32" CPU_FLAGS_ARM="crc32 neon" CPU_FLAGS_PPC="altivec vsx2 vsx3" CPU_FLAGS_X86="avx2 avx512_vnni avx512f pclmul sse2 sse4_1 sse4_2 ssse3 vpclmulqdq"}
     Installed versions:  2.3.2^t(19:22:47 07/01/2026)(-compat -static-libs -test ABI_MIPS="-n32 -n64 -o32" ABI_S390="-32 -64" ABI_X86="64 -32 -x32" CPU_FLAGS_ARM="-crc32 -neon" CPU_FLAGS_PPC="-altivec -vsx2 -vsx3" CPU_FLAGS_X86="avx2 pclmul sse2 sse4_1 sse4_2 ssse3 -avx512_vnni -avx512f -vpclmulqdq")

static-libs seems there.

Thks 4 ur attention, interest & support.

trubicoid · Post by **trubicoid** » Fri Jan 09, 2026 9:19 am

CaptainBlood wrote:
trubicoid wrote:However, the subsequent update wanted to pull virtual/zlib, which pulls sys-lib/zlib again! I think, it is because of the static-libs, zlib-ng does not have them, right?
Code: Select all
[I] sys-libs/zlib-ng
     Available versions:  2.2.5^t 2.2.5-r1^t 2.3.2^t {compat static-libs test ABI_MIPS="n32 n64 o32" ABI_S390="32 64" ABI_X86="32 64 x32" CPU_FLAGS_ARM="crc32 neon" CPU_FLAGS_PPC="altivec vsx2 vsx3" CPU_FLAGS_X86="avx2 avx512_vnni avx512f pclmul sse2 sse4_1 sse4_2 ssse3 vpclmulqdq"}
     Installed versions:  2.3.2^t(19:22:47 07/01/2026)(-compat -static-libs -test ABI_MIPS="-n32 -n64 -o32" ABI_S390="-32 -64" ABI_X86="64 -32 -x32" CPU_FLAGS_ARM="-crc32 -neon" CPU_FLAGS_PPC="-altivec -vsx2 -vsx3" CPU_FLAGS_X86="avx2 pclmul sse2 sse4_1 sse4_2 ssse3 -avx512_vnni -avx512f -vpclmulqdq")
static-libs seems there.

Thks 4 ur attention, interest & support.

You are right, I can't reproduce the problem any more:

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# USE=static-libs emerge -pv virtual/zlib

These are the packages that would be merged, in order:

Calculating dependencies... done!
Dependency resolution took 11.17 s (backtrack: 0/20).

[ebuild   R    ] virtual/zlib-1.3.1-r1:0/1::gentoo  USE="static-libs*" 0 KiB
[ebuild   R    ] sys-libs/zlib-ng-2.3.2::gentoo  USE="compat static-libs* -test" CPU_FLAGS_X86="pclmul sse2 sse4_1 sse4_2 ssse3 -avx2 -avx512_vnni -avx512f -vpclmulqdq" 0 KiB

Total: 2 packages (2 reinstalls), Size of downloads: 0 KiB

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But before removing static-libs helped. With it, virtual/zlib always wanted to pull sys-libs/zlib.

CaptainBlood · Post by **CaptainBlood** » Fri Jan 09, 2026 4:59 pm

Starting from the following point from a previous post:

CaptainBlood wrote:

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emerge -p -a -uvDU @world sys-libs/zlib-ng --exclude zig
Dependency resolution took 68.68 s (backtrack: 0/20).

[ebuild   R    ] sys-libs/zlib-ng-2.3.2::gentoo  USE="compat* -static-libs -test" ABI_X86="-32 (64) (-x32)" CPU_FLAGS_X86="avx2 -avx512_vnni -avx512f pclmul sse2 sse4_1 sse4_2 ssse3 -vpclmulqdq" 0 KiB
[blocks B      ] sys-libs/zlib-ng[compat] ("sys-libs/zlib-ng[compat]" is soft blocking sys-libs/zlib-1.3.1-r1)
[blocks B      ] sys-libs/zlib ("sys-libs/zlib" is soft blocking sys-libs/zlib-ng-2.3.2)

Total: 1 package (1 reinstall), Size of downloads: 0 KiB
Conflict: 2 blocks (2 unsatisfied)

 * Error: The above package list contains packages which cannot be
 * installed at the same time on the same system.

  (sys-libs/zlib-1.3.1-r1:0/1::gentoo, installed) pulled in by
    >=sys-libs/zlib-1.2.8-r1:0/1=[abi_x86_64(-)] required by (dev-libs/libxml2-compat-2.13.9:2/2::gentoo, installed) USE="-icu -lzma -readline -test" ABI_X86="-32 (64) (-x32)"
    sys-libs/zlib:0/1= required by (media-gfx/pngcrush-1.8.13:0/0::gentoo, installed) USE="" ABI_X86="(64)"
    sys-libs/zlib:0/1= required by (media-libs/libharu-2.4.5:0/2.4::gentoo, installed) USE="" ABI_X86="(64)"
    sys-libs/zlib:0/1=[abi_x86_64(-)] required by (media-libs/leptonica-1.85.0:0/6::gentoo, installed) USE="-gif jpeg -jpeg2k -png -static-libs -test tiff -utils -webp zlib" ABI_X86="-32 (64) (-x32)"
    sys-libs/zlib:0/1= required by (sci-libs/hdf5-1.14.6-r2:0/310-cmake::gentoo, installed) USE="cxx -debug fortran hl mpi -szip -test threads unsupported zlib" ABI_X86="(64)"
    sys-libs/zlib:0/1= required by (net-misc/aria2-1.37.0:0/0::gentoo, installed) USE="-adns -bittorrent (-gnutls) -jemalloc -libuv -libxml2 metalink -nettle -nls -scripts -sqlite -ssh ssl -tcmalloc -test xmlrpc" ABI_X86="(64)"
    sys-libs/zlib:0/1= required by (dev-lang/rust-1.81.0-r101:1.81.0/1.81.0::gentoo, installed) USE="(-big-endian) clippy -debug -dist doc (-llvm-libunwind) -lto miri nightly -parallel-compiler rust-analyzer rust-src rustfmt -system-llvm -test verify-sig wasm" ABI_X86="-32 (64) (-x32)" CPU_FLAGS_X86="sse2" LLVM_SLOT="(18)" LLVM_TARGETS="-AArch64 -AMDGPU -ARC -ARM -AVR -BPF -CSKY -DirectX -Hexagon -Lanai -LoongArch -M68k -MSP430 -Mips -NVPTX -PowerPC -RISCV -SPIRV -Sparc -SystemZ -VE WebAssembly (X86) -XCore -Xtensa"
    sys-libs/zlib required by (sys-devel/mold-9999:0/0::local, installed) USE="-debug -test" ABI_X86="(64)"
    sys-libs/zlib:0/1=[abi_x86_64(-)] required by (llvm-core/llvm-19.1.7:19/19.1::gentoo, installed) USE="binutils-plugin -debug (-debuginfod) doc -exegesis -libedit -libffi -test verify-sig -xml z3 zstd" ABI_X86="-32 (64) (-x32)" LLVM_TARGETS="(AArch64) (AMDGPU) -ARC (ARM) (AVR) (BPF) -CSKY -DirectX (Hexagon) (Lanai) (LoongArch) -M68k (MSP430) (Mips) (NVPTX) (PowerPC) (RISCV) SPIRV (Sparc) (SystemZ) (VE) (WebAssembly) (X86) (XCore) -Xtensa"
    sys-libs/zlib:0/1=[abi_x86_64(-)] required by (llvm-core/llvm-15.0.7-r7:15/15::gentoo, installed) USE="binutils-plugin -debug -doc -exegesis -libedit -libffi -ncurses -test verify-sig -xar -xml z3 zstd" ABI_X86="-32 (64) (-x32)" LLVM_TARGETS="(AArch64) (AMDGPU) (-ARC) (ARM) (AVR) (BPF) (-CSKY) (-DirectX) (Hexagon) (Lanai) (-LoongArch) (-M68k) (MSP430) (Mips) (NVPTX) (PowerPC) (RISCV) (-SPIRV) (Sparc) (SystemZ) (VE) (WebAssembly) (X86) (XCore)"
    sys-libs/zlib:0/1= required by (media-gfx/potrace-1.16-r1:0/0::gentoo, installed) USE="-metric" ABI_X86="(64)"
    sys-libs/zlib:0/1= required by (gui-apps/wlogout-1.2.2-r1-1:0/0::guru, installed) USE="" ABI_X86="(64)"
    sys-libs/zlib:0/1= required by (dev-libs/libmirage-3.2.10:0/11::gentoo, installed) USE="-doc -introspection" ABI_X86="(64)"
    sys-libs/zlib:0/1= required by (dev-lang/rust-1.82.0-r103:1.82.0/1.82.0::gentoo, installed) USE="(-big-endian) clippy -debug -dist doc (-llvm-libunwind) -lto miri nightly -parallel-compiler rust-analyzer rust-src rustfmt -system-llvm -test verify-sig wasm" ABI_X86="-32 (64) (-x32)" CPU_FLAGS_X86="sse2" LLVM_SLOT="(19)" LLVM_TARGETS="-AArch64 -AMDGPU -ARC -ARM -AVR -BPF -CSKY -DirectX -Hexagon -Lanai -LoongArch -M68k -MSP430 -Mips -NVPTX -PowerPC -RISCV -SPIRV -Sparc -SystemZ -VE WebAssembly (X86) -XCore -Xtensa"
    sys-libs/zlib required by (app-accessibility/julius-4.6:0/0::local, installed) USE="alsa -oss -portaudio -pulseaudio sndfile" ABI_X86="(64)" L10N="-ja"
    sys-libs/zlib:0/1= required by (gnome-extra/evolution-data-server-3.56.2-r1:0/64-11-21-4-3-27-2-27-4-0::gentoo, installed) USE="-berkdb -gnome-online-accounts -gtk -gtk-doc -introspection -kerberos -ldap -oauth-gtk3 -oauth-gtk4 -sound -test -vala -weather" ABI_X86="(64)"
    sys-libs/zlib:0/1= required by (dev-lang/rust-1.90.0-r1:1.90.0/1.90.0::gentoo, installed) USE="(-big-endian) clippy -debug -dist doc (-llvm-libunwind) -lto rust-analyzer rust-src rustfmt -system-llvm -test verify-sig" ABI_X86="-32 (64) (-x32)" CPU_FLAGS_X86="sse2" LLVM_SLOT="(20)" LLVM_TARGETS="-AArch64 -AMDGPU -ARC -ARM -AVR -BPF -CSKY -DirectX -Hexagon -Lanai -LoongArch -M68k -MSP430 -Mips -NVPTX -PowerPC -RISCV -SPIRV -Sparc -SystemZ -VE WebAssembly (X86) -XCore -Xtensa" RUST_SYSROOTS="-bpf wasm"
    sys-libs/zlib:0/1= required by (media-libs/openjpeg-2.5.3-r1:2/7::gentoo, installed) USE="-doc -test" ABI_X86="-32 (64) (-x32)"
    sys-libs/zlib[static-libs(+)] required by (media-gfx/splashutils-1.5.4.4-r101:0/0::local, installed) USE="fbcondecor -gpm -hardened -klibc png (-split-usr) -truetype" ABI_X86="(64)"
    sys-libs/zlib:0/1= required by (dev-lang/rust-1.89.0:1.89.0/1.89.0::gentoo, installed) USE="(-big-endian) clippy -debug -dist doc (-llvm-libunwind) -lto rust-analyzer rust-src rustfmt -system-llvm -test verify-sig wasm" ABI_X86="-32 (64) (-x32)" CPU_FLAGS_X86="sse2" LLVM_SLOT="(20)" LLVM_TARGETS="-AArch64 -AMDGPU -ARC -ARM -AVR -BPF -CSKY -DirectX -Hexagon -Lanai -LoongArch -M68k -MSP430 -Mips -NVPTX -PowerPC -RISCV -SPIRV -Sparc -SystemZ -VE WebAssembly (X86) -XCore -Xtensa"
    >=sys-libs/zlib-1.3.1[abi_x86_32(-)?,abi_x86_64(-)?,abi_x86_x32(-)?,abi_mips_n32(-)?,abi_mips_n64(-)?,abi_mips_o32(-)?,abi_s390_32(-)?,abi_s390_64(-)?,minizip] (>=sys-libs/zlib-1.3.1[abi_x86_64(-),minizip]) required by (virtual/minizip-1.3.1:0/1::gentoo, installed) USE="-static-libs" ABI_X86="-32 (64) (-x32)"
    sys-libs/zlib:0/1= required by (games-fps/xonotic-0.8.6-1:0/0::gentoo, installed) USE="X alsa ode -sdl" ABI_X86="(64)"
    sys-libs/zlib:= required by (app-text/stardict-4.0.0_pre20170304-r2:0/0::mv, installed) USE="-advertisement -cal -canberra -debug -dictdotcn -espeak -examples -flite -fortune -gnome -gucharmap -htmlparse -info -man -perl -powerwordparse -pronounce -qqwry -spell -tools -updateinfo -wikiparse -wordnet -xdxfparse -youdaodict" ABI_X86="(64)"
    sys-libs/zlib:0/1=[abi_x86_64(-)] required by (dev-db/sqlite-3.50.4:3/3::gentoo, installed) USE="-debug -doc -icu -readline secure-delete -static-libs -tcl -test -tools" ABI_X86="-32 (64) (-x32)"
    sys-libs/zlib:0/1=[abi_x86_64(-)] required by (dev-libs/boost-1.88.0-r1:0/1.88.0::gentoo, installed) USE="-bzip2 context -debug -doc icu -lzma mpi nls -numpy python stacktrace -test -test-full -tools zlib -zstd" ABI_X86="-32 (64) (-x32)" PYTHON_TARGETS="-python3_11 python3_12 -python3_13"
    sys-libs/zlib:0/1= required by (net-misc/dhcp-4.4.3_p1-r6:0/0::gentoo, installed) USE="-client -ipv6 -ldap (-selinux) server -ssl -vim-syntax" ABI_X86="(64)"
    sys-libs/zlib:0/1= required by (dev-lang/rust-1.84.1-r2:1.84.1/1.84.1::gentoo, installed) USE="(-big-endian) clippy -debug -dist doc (-llvm-libunwind) -lto miri nightly -parallel-compiler rust-analyzer rust-src rustfmt -system-llvm -test verify-sig wasm" ABI_X86="-32 (64) (-x32)" CPU_FLAGS_X86="sse2" LLVM_SLOT="(19)" LLVM_TARGETS="-AArch64 -AMDGPU -ARC -ARM -AVR -BPF -CSKY -DirectX -Hexagon -Lanai -LoongArch -M68k -MSP430 -Mips -NVPTX -PowerPC -RISCV -SPIRV -Sparc -SystemZ -VE WebAssembly (X86) -XCore -Xtensa"
    sys-libs/zlib:0/1= required by (dev-lang/rust-1.83.0-r3:1.83.0/1.83.0::gentoo, installed) USE="(-big-endian) clippy -debug -dist doc (-llvm-libunwind) -lto miri nightly -parallel-compiler rust-analyzer rust-src rustfmt -system-llvm -test verify-sig wasm" ABI_X86="-32 (64) (-x32)" CPU_FLAGS_X86="sse2" LLVM_SLOT="(19)" LLVM_TARGETS="-AArch64 -AMDGPU -ARC -ARM -AVR -BPF -CSKY -DirectX -Hexagon -Lanai -LoongArch -M68k -MSP430 -Mips -NVPTX -PowerPC -RISCV -SPIRV -Sparc -SystemZ -VE WebAssembly (X86) -XCore -Xtensa"
    sys-libs/zlib:0/1= required by (app-text/stardict-4.0.0_pre20170304-r2:0/0::mv, installed) USE="-advertisement -cal -canberra -debug -dictdotcn -espeak -examples -flite -fortune -gnome -gucharmap -htmlparse -info -man -perl -powerwordparse -pronounce -qqwry -spell -tools -updateinfo -wikiparse -wordnet -xdxfparse -youdaodict" ABI_X86="(64)"
    sys-libs/zlib:0/1=[abi_x86_64(-)] required by (llvm-core/llvm-20.1.8:20/20.1::gentoo, installed) USE="binutils-plugin -debug (-debuginfod) -doc -exegesis -libedit -libffi -test verify-sig -xml z3 zstd" ABI_X86="-32 (64) (-x32)" LLVM_TARGETS="(AArch64) (AMDGPU) -ARC (ARM) (AVR) (BPF) -CSKY -DirectX (Hexagon) (Lanai) (LoongArch) -M68k (MSP430) (Mips) (NVPTX) (PowerPC) (RISCV) (SPIRV) (Sparc) (SystemZ) (VE) (WebAssembly) (X86) (XCore) -Xtensa"
    sys-libs/zlib:0/1= required by (media-gfx/openvdb-11.0.0-r1:0/11.0::gentoo, installed) USE="-abi10-compat abi11-compat -abi12-compat -abi9-compat -alembic ax blosc (-cuda) -doc -examples -jpeg -nanovdb -numpy -openexr -png -python -static-libs -test -utils zlib" ABI_X86="(64)" CPU_FLAGS_X86="avx sse4_2" LLVM_SLOT="15" PYTHON_SINGLE_TARGET="-python3_11 -python3_12"
    sys-libs/zlib:0/1= required by (dev-lang/rust-1.79.0-r101:1.79.0/1.79.0::gentoo, installed) USE="(-big-endian) clippy -debug -dist doc (-llvm-libunwind) -lto miri nightly -parallel-compiler rust-analyzer rust-src rustfmt -system-llvm -test verify-sig wasm" ABI_X86="-32 (64) (-x32)" CPU_FLAGS_X86="sse2" LLVM_SLOT="(18)" LLVM_TARGETS="-AArch64 -AMDGPU -ARC -ARM -AVR -BPF -CSKY -DirectX -Hexagon -Lanai -LoongArch -M68k -MSP430 -Mips -NVPTX -PowerPC -RISCV -SPIRV -Sparc -SystemZ -VE WebAssembly (X86) -XCore -Xtensa"
    sys-libs/zlib:0/1= required by (dev-lang/rust-1.86.0-r2:1.86.0/1.86.0::gentoo, installed) USE="(-big-endian) clippy -debug -dist doc (-llvm-libunwind) -lto rust-analyzer rust-src rustfmt -system-llvm -test verify-sig wasm" ABI_X86="-32 (64) (-x32)" CPU_FLAGS_X86="sse2" LLVM_SLOT="(19)" LLVM_TARGETS="-AArch64 -AMDGPU -ARC -ARM -AVR -BPF -CSKY -DirectX -Hexagon -Lanai -LoongArch -M68k -MSP430 -Mips -NVPTX -PowerPC -RISCV -SPIRV -Sparc -SystemZ -VE WebAssembly (X86) -XCore -Xtensa"
    sys-libs/zlib:0/1= required by (dev-python/pillow-11.3.0:0/0::gentoo, installed) USE="-avif -debug -examples -imagequant jpeg jpeg2k lcms -test tiff -tk truetype webp -xcb zlib" ABI_X86="(64)" PYTHON_TARGETS="(-pypy3_11) -python3_11 python3_12 -python3_13 -python3_14"
    sys-libs/zlib:0/1= required by (dev-lang/rust-1.91.0:1.91.0/1.91.0::gentoo, installed) USE="(-big-endian) clippy -debug -dist doc (-llvm-libunwind) -lto rust-analyzer rust-src rustfmt -system-llvm -test verify-sig" ABI_X86="-32 (64) (-x32)" CPU_FLAGS_X86="sse2" LLVM_SLOT="(21)" LLVM_TARGETS="-AArch64 -AMDGPU -ARC -ARM -AVR -BPF -CSKY -DirectX -Hexagon -Lanai -LoongArch -M68k -MSP430 -Mips -NVPTX -PowerPC -RISCV -SPIRV -Sparc -SystemZ -VE WebAssembly (X86) -XCore -Xtensa" RUST_SYSROOTS="-bpf wasm"
    sys-libs/zlib:0/1= required by (dev-lang/rust-1.80.1-r101:1.80.1/1.80.1::gentoo, installed) USE="(-big-endian) clippy -debug -dist doc (-llvm-libunwind) -lto miri nightly -parallel-compiler rust-analyzer rust-src rustfmt -system-llvm -test verify-sig wasm" ABI_X86="-32 (64) (-x32)" CPU_FLAGS_X86="sse2" LLVM_SLOT="(18)" LLVM_TARGETS="-AArch64 -AMDGPU -ARC -ARM -AVR -BPF -CSKY -DirectX -Hexagon -Lanai -LoongArch -M68k -MSP430 -Mips -NVPTX -PowerPC -RISCV -SPIRV -Sparc -SystemZ -VE WebAssembly (X86) -XCore -Xtensa"
    sys-libs/zlib:0/1= required by (sys-devel/bpf-toolchain-15.2.0_p1:0/0::gentoo, installed) USE="bin-symlinks custom-cflags strip" ABI_X86="(64)"
    sys-libs/zlib:0/1= required by (llvm-core/lld-18.1.8-1:18/18.1::gentoo, installed) USE="-debug -test verify-sig zstd" ABI_X86="(64)"
    sys-libs/zlib:0/1= required by (dev-lang/rust-1.85.1-r1:1.85.1/1.85.1::gentoo, installed) USE="(-big-endian) clippy -debug -dist doc (-llvm-libunwind) -lto rust-analyzer rust-src rustfmt -system-llvm -test verify-sig wasm" ABI_X86="-32 (64) (-x32)" CPU_FLAGS_X86="sse2" LLVM_SLOT="(19)" LLVM_TARGETS="-AArch64 -AMDGPU -ARC -ARM -AVR -BPF -CSKY -DirectX -Hexagon -Lanai -LoongArch -M68k -MSP430 -Mips -NVPTX -PowerPC -RISCV -SPIRV -Sparc -SystemZ -VE WebAssembly (X86) -XCore -Xtensa"
    sys-libs/zlib:0/1= required by (sys-apps/vbetool-1.2.2:0/0::gentoo, installed) USE="(-selinux)" ABI_X86="(64)"
    >=sys-libs/zlib-1.3.1[abi_x86_32(-)?,abi_x86_64(-)?,abi_x86_x32(-)?,abi_mips_n32(-)?,abi_mips_n64(-)?,abi_mips_o32(-)?,abi_s390_32(-)?,abi_s390_64(-)?,static-libs?] (>=sys-libs/zlib-1.3.1[abi_x86_64(-),static-libs]) required by (virtual/zlib-1.3.1-r1:0/1::gentoo, installed) USE="static-libs" ABI_X86="-32 (64) (-x32)"
    sys-libs/zlib:0/1=[abi_x86_64(-)] required by (llvm-core/llvm-18.1.8-r6:18/18.1::gentoo, installed) USE="binutils-plugin -debug (-debuginfod) -doc -exegesis -libedit -libffi -ncurses -test verify-sig -xml z3 zstd" ABI_X86="-32 (64) (-x32)" LLVM_TARGETS="(AArch64) (AMDGPU) -ARC (ARM) (AVR) (BPF) -CSKY -DirectX (Hexagon) (Lanai) (LoongArch) -M68k (MSP430) (Mips) (NVPTX) (PowerPC) (RISCV) -SPIRV (Sparc) (SystemZ) (VE) (WebAssembly) (X86) (XCore) -Xtensa"
    sys-libs/zlib:0/1= required by (llvm-core/lld-19.1.7-1:19/19.1::gentoo, installed) USE="-debug -test verify-sig zstd" ABI_X86="(64)"
    sys-libs/zlib:0/1= required by (dev-lang/rust-1.88.0:1.88.0/1.88.0::gentoo, installed) USE="(-big-endian) clippy -debug -dist doc (-llvm-libunwind) -lto rust-analyzer rust-src rustfmt -system-llvm -test verify-sig wasm" ABI_X86="-32 (64) (-x32)" CPU_FLAGS_X86="sse2" LLVM_SLOT="(20)" LLVM_TARGETS="-AArch64 -AMDGPU -ARC -ARM -AVR -BPF -CSKY -DirectX -Hexagon -Lanai -LoongArch -M68k -MSP430 -Mips -NVPTX -PowerPC -RISCV -SPIRV -Sparc -SystemZ -VE WebAssembly (X86) -XCore -Xtensa"
    sys-libs/zlib:0/1= required by (app-text/podofo-0.10.3-r1:0/2::gentoo, installed) USE="-fontconfig -idn -jpeg -png -test -tiff -tools" ABI_X86="(64)"
    sys-libs/zlib:0/1= required by (sci-mathematics/glpk-5.0-r3:0/40::gentoo, installed) USE="-doc -examples gmp -mysql -odbc" ABI_X86="(64)"
    >=sys-libs/zlib-1.1.3:0/1= required by (dev-lang/python-2.7.18_p16-r2:2.7/2.7::gentoo, installed) USE="(-berkdb) -bluetooth -build -examples -gdbm -ncurses -readline -sqlite -ssl -tk -valgrind verify-sig -wininst -xml" ABI_X86="(64)"
    sys-libs/zlib:0/1= required by (dev-lang/rust-1.87.0-r1:1.87.0/1.87.0::gentoo, installed) USE="(-big-endian) clippy -debug -dist doc (-llvm-libunwind) -lto rust-analyzer rust-src rustfmt -system-llvm -test verify-sig wasm" ABI_X86="-32 (64) (-x32)" CPU_FLAGS_X86="sse2" LLVM_SLOT="(20)" LLVM_TARGETS="-AArch64 -AMDGPU -ARC -ARM -AVR -BPF -CSKY -DirectX -Hexagon -Lanai -LoongArch -M68k -MSP430 -Mips -NVPTX -PowerPC -RISCV -SPIRV -Sparc -SystemZ -VE WebAssembly (X86) -XCore -Xtensa"
    sys-libs/zlib required by (media-gfx/ipe-7.2.26:0/0::mv, installed) USE="" ABI_X86="(64)" LUA_SINGLE_TARGET="-lua5-3 lua5-4"
    sys-libs/zlib:0/1= required by (net-p2p/transmission-4.0.6-r6:0/0::gentoo, installed) USE="-appindicator -cli -debug gtk -mbedtls -nls -qt6 -systemd -test" ABI_X86="(64)"
    >=sys-libs/zlib-1.2.13:0/1=[abi_x86_64(-)] required by (dev-db/mysql-connector-c-8.0.36-1:0/21::gentoo, installed) USE="-ldap -static-libs" ABI_X86="-32 (64) (-x32)"

  (sys-libs/zlib-ng-2.3.2:0/0::gentoo, ebuild scheduled for merge) pulled in by
    sys-libs/zlib-ng
    sys-libs/zlib-ng[abi_x86_32(-)?,abi_x86_64(-)?,abi_x86_x32(-)?,abi_mips_n32(-)?,abi_mips_n64(-)?,abi_mips_o32(-)?,abi_s390_32(-)?,abi_s390_64(-)?] (sys-libs/zlib-ng[abi_x86_64(-)]) required by (sys-libs/minizip-ng-4.0.10-r1:0/4::gentoo, installed) USE="-compat -lzma -openssl -test -zstd" ABI_X86="-32 (64) (-x32)"

I decided to follow Hu's advice, ie to rebuild packages shown as requiring sys-libs/zlib but the long lasting building ones:
This now brings the following:

Code: Select all

emerge -p -uvDU @world --exclude zig

These are the packages that would be merged, in reverse order:

Calculating dependencies  .!!! /etc/portage/package.env references non-existent file: /etc/portage/env/mold-error

... done!
Dependency resolution took 67.53 s (backtrack: 0/20).

[nomerge       ] x11-wm/xpra-6.2.5-r1::gentoo  USE="X -avif -brotli client -clipboard -crypt -csc (-cuda) -cups -dbus -debug (-doc) -examples -gstreamer -gtk3 -html -ibus -jpeg -lz4 -mdns minimal -oauth -opengl -openh264 -pinentry -pulseaudio -qrcode server -sound -systemd -test -trayicon -udev -vpx -webcam -webp -x264 -xdg -xinerama" PYTHON_SINGLE_TARGET="-python3_11 python3_12 -python3_13" VIDEO_CARDS="-nvidia" 
[nomerge       ]  x11-base/xorg-server-21.1.20:0/21.1.20::gentoo  USE="-debug elogind -minimal (-selinux) -suid -systemd -test udev -unwind -xcsecurity -xephyr -xnest xorg xvfb" 
[nomerge       ]   media-libs/mesa-25.2.8::gentoo  USE="X -debug llvm -lm-sensors opencl (opengl) proprietary-codecs -sysprof -test -unwind vaapi -valgrind vdpau vulkan wayland zstd" ABI_X86="-32 (64) (-x32)" CPU_FLAGS_X86="sse2" LLVM_SLOT="-18 -19 20 -21" VIDEO_CARDS="-asahi -d3d12 (-freedreno) intel -lavapipe (-lima) -nouveau -nvk (-panfrost) -r300 -r600 -radeon -radeonsi (-v3d) (-vc4) -virgl (-vivante) -vmware -zink" 
[nomerge       ]    llvm-core/llvm-20.1.8:20/20.1::gentoo  USE="binutils-plugin -debug (-debuginfod) -doc -exegesis -libedit -libffi -test verify-sig -xml z3 zstd" ABI_X86="-32 (64) (-x32)" LLVM_TARGETS="(AArch64) (AMDGPU) -ARC (ARM) (AVR) (BPF) -CSKY -DirectX (Hexagon) (Lanai) (LoongArch) -M68k (MSP430) (Mips) (NVPTX) (PowerPC) (RISCV) (SPIRV) (Sparc) (SystemZ) (VE) (WebAssembly) (X86) (XCore) -Xtensa" 
[ebuild  N     ]     sys-libs/zlib-1.3.1-r1:0/1::gentoo  USE="minizip static-libs verify-sig" ABI_X86="-32 (64) (-x32)" 0 KiB
[blocks B      ] sys-libs/zlib-ng[compat] ("sys-libs/zlib-ng[compat]" is soft blocking sys-libs/zlib-1.3.1-r1)
[blocks B      ] sys-libs/zlib ("sys-libs/zlib" is soft blocking sys-libs/zlib-ng-2.3.2)

Total: 1 package (1 new), Size of downloads: 0 KiB
Conflict: 2 blocks (2 unsatisfied)

 * Error: The above package list contains packages which cannot be
 * installed at the same time on the same system.

  (sys-libs/zlib-1.3.1-r1:0/1::gentoo, ebuild scheduled for merge) pulled in by
    sys-libs/zlib required by (media-gfx/ipe-7.2.26:0/0::mv, installed) USE="" ABI_X86="(64)" LUA_SINGLE_TARGET="-lua5-3 lua5-4"
    sys-libs/zlib:0/1= required by (dev-lang/rust-1.86.0-r2:1.86.0/1.86.0::gentoo, installed) USE="(-big-endian) clippy -debug -dist doc (-llvm-libunwind) -lto rust-analyzer rust-src rustfmt -system-llvm -test verify-sig wasm" ABI_X86="-32 (64) (-x32)" CPU_FLAGS_X86="sse2" LLVM_SLOT="(19)" LLVM_TARGETS="-AArch64 -AMDGPU -ARC -ARM -AVR -BPF -CSKY -DirectX -Hexagon -Lanai -LoongArch -M68k -MSP430 -Mips -NVPTX -PowerPC -RISCV -SPIRV -Sparc -SystemZ -VE WebAssembly (X86) -XCore -Xtensa"
    sys-libs/zlib:0/1= required by (app-text/stardict-4.0.0_pre20170304-r2:0/0::mv, installed) USE="-advertisement -cal -canberra -debug -dictdotcn -espeak -examples -flite -fortune -gnome -gucharmap -htmlparse -info -man -perl -powerwordparse -pronounce -qqwry -spell -tools -updateinfo -wikiparse -wordnet -xdxfparse -youdaodict" ABI_X86="(64)"
    sys-libs/zlib:0/1= required by (dev-lang/rust-1.88.0:1.88.0/1.88.0::gentoo, installed) USE="(-big-endian) clippy -debug -dist doc (-llvm-libunwind) -lto rust-analyzer rust-src rustfmt -system-llvm -test verify-sig wasm" ABI_X86="-32 (64) (-x32)" CPU_FLAGS_X86="sse2" LLVM_SLOT="(20)" LLVM_TARGETS="-AArch64 -AMDGPU -ARC -ARM -AVR -BPF -CSKY -DirectX -Hexagon -Lanai -LoongArch -M68k -MSP430 -Mips -NVPTX -PowerPC -RISCV -SPIRV -Sparc -SystemZ -VE WebAssembly (X86) -XCore -Xtensa"
    sys-libs/zlib:0/1=[abi_x86_64(-)] required by (llvm-core/llvm-20.1.8:20/20.1::gentoo, installed) USE="binutils-plugin -debug (-debuginfod) -doc -exegesis -libedit -libffi -test verify-sig -xml z3 zstd" ABI_X86="-32 (64) (-x32)" LLVM_TARGETS="(AArch64) (AMDGPU) -ARC (ARM) (AVR) (BPF) -CSKY -DirectX (Hexagon) (Lanai) (LoongArch) -M68k (MSP430) (Mips) (NVPTX) (PowerPC) (RISCV) (SPIRV) (Sparc) (SystemZ) (VE) (WebAssembly) (X86) (XCore) -Xtensa"
    sys-libs/zlib:0/1=[abi_x86_64(-)] required by (llvm-core/llvm-15.0.7-r7:15/15::gentoo, installed) USE="binutils-plugin -debug -doc -exegesis -libedit -libffi -ncurses -test verify-sig -xar -xml z3 zstd" ABI_X86="-32 (64) (-x32)" LLVM_TARGETS="(AArch64) (AMDGPU) (-ARC) (ARM) (AVR) (BPF) (-CSKY) (-DirectX) (Hexagon) (Lanai) (-LoongArch) (-M68k) (MSP430) (Mips) (NVPTX) (PowerPC) (RISCV) (-SPIRV) (Sparc) (SystemZ) (VE) (WebAssembly) (X86) (XCore)"
    sys-libs/zlib:0/1= required by (dev-lang/rust-1.81.0-r101:1.81.0/1.81.0::gentoo, installed) USE="(-big-endian) clippy -debug -dist doc (-llvm-libunwind) -lto miri nightly -parallel-compiler rust-analyzer rust-src rustfmt -system-llvm -test verify-sig wasm" ABI_X86="-32 (64) (-x32)" CPU_FLAGS_X86="sse2" LLVM_SLOT="(18)" LLVM_TARGETS="-AArch64 -AMDGPU -ARC -ARM -AVR -BPF -CSKY -DirectX -Hexagon -Lanai -LoongArch -M68k -MSP430 -Mips -NVPTX -PowerPC -RISCV -SPIRV -Sparc -SystemZ -VE WebAssembly (X86) -XCore -Xtensa"
    sys-libs/zlib:0/1= required by (dev-lang/rust-1.85.1-r1:1.85.1/1.85.1::gentoo, installed) USE="(-big-endian) clippy -debug -dist doc (-llvm-libunwind) -lto rust-analyzer rust-src rustfmt -system-llvm -test verify-sig wasm" ABI_X86="-32 (64) (-x32)" CPU_FLAGS_X86="sse2" LLVM_SLOT="(19)" LLVM_TARGETS="-AArch64 -AMDGPU -ARC -ARM -AVR -BPF -CSKY -DirectX -Hexagon -Lanai -LoongArch -M68k -MSP430 -Mips -NVPTX -PowerPC -RISCV -SPIRV -Sparc -SystemZ -VE WebAssembly (X86) -XCore -Xtensa"
    sys-libs/zlib:0/1= required by (dev-lang/rust-1.79.0-r101:1.79.0/1.79.0::gentoo, installed) USE="(-big-endian) clippy -debug -dist doc (-llvm-libunwind) -lto miri nightly -parallel-compiler rust-analyzer rust-src rustfmt -system-llvm -test verify-sig wasm" ABI_X86="-32 (64) (-x32)" CPU_FLAGS_X86="sse2" LLVM_SLOT="(18)" LLVM_TARGETS="-AArch64 -AMDGPU -ARC -ARM -AVR -BPF -CSKY -DirectX -Hexagon -Lanai -LoongArch -M68k -MSP430 -Mips -NVPTX -PowerPC -RISCV -SPIRV -Sparc -SystemZ -VE WebAssembly (X86) -XCore -Xtensa"
    >=sys-libs/zlib-1.3.1[abi_x86_32(-)?,abi_x86_64(-)?,abi_x86_x32(-)?,abi_mips_n32(-)?,abi_mips_n64(-)?,abi_mips_o32(-)?,abi_s390_32(-)?,abi_s390_64(-)?,static-libs?] (>=sys-libs/zlib-1.3.1[abi_x86_64(-),static-libs]) required by (virtual/zlib-1.3.1-r1:0/1::gentoo, installed) USE="static-libs" ABI_X86="-32 (64) (-x32)"
    sys-libs/zlib:0/1=[abi_x86_64(-)] required by (llvm-core/llvm-18.1.8-r6:18/18.1::gentoo, installed) USE="binutils-plugin -debug (-debuginfod) -doc -exegesis -libedit -libffi -ncurses -test verify-sig -xml z3 zstd" ABI_X86="-32 (64) (-x32)" LLVM_TARGETS="(AArch64) (AMDGPU) -ARC (ARM) (AVR) (BPF) -CSKY -DirectX (Hexagon) (Lanai) (LoongArch) -M68k (MSP430) (Mips) (NVPTX) (PowerPC) (RISCV) -SPIRV (Sparc) (SystemZ) (VE) (WebAssembly) (X86) (XCore) -Xtensa"
    sys-libs/zlib:0/1= required by (dev-lang/rust-1.89.0:1.89.0/1.89.0::gentoo, installed) USE="(-big-endian) clippy -debug -dist doc (-llvm-libunwind) -lto rust-analyzer rust-src rustfmt -system-llvm -test verify-sig wasm" ABI_X86="-32 (64) (-x32)" CPU_FLAGS_X86="sse2" LLVM_SLOT="(20)" LLVM_TARGETS="-AArch64 -AMDGPU -ARC -ARM -AVR -BPF -CSKY -DirectX -Hexagon -Lanai -LoongArch -M68k -MSP430 -Mips -NVPTX -PowerPC -RISCV -SPIRV -Sparc -SystemZ -VE WebAssembly (X86) -XCore -Xtensa"
    sys-libs/zlib:= required by (app-text/stardict-4.0.0_pre20170304-r2:0/0::mv, installed) USE="-advertisement -cal -canberra -debug -dictdotcn -espeak -examples -flite -fortune -gnome -gucharmap -htmlparse -info -man -perl -powerwordparse -pronounce -qqwry -spell -tools -updateinfo -wikiparse -wordnet -xdxfparse -youdaodict" ABI_X86="(64)"
    sys-libs/zlib:0/1= required by (dev-lang/rust-1.87.0-r1:1.87.0/1.87.0::gentoo, installed) USE="(-big-endian) clippy -debug -dist doc (-llvm-libunwind) -lto rust-analyzer rust-src rustfmt -system-llvm -test verify-sig wasm" ABI_X86="-32 (64) (-x32)" CPU_FLAGS_X86="sse2" LLVM_SLOT="(20)" LLVM_TARGETS="-AArch64 -AMDGPU -ARC -ARM -AVR -BPF -CSKY -DirectX -Hexagon -Lanai -LoongArch -M68k -MSP430 -Mips -NVPTX -PowerPC -RISCV -SPIRV -Sparc -SystemZ -VE WebAssembly (X86) -XCore -Xtensa"
    sys-libs/zlib:0/1= required by (dev-lang/rust-1.90.0-r1:1.90.0/1.90.0::gentoo, installed) USE="(-big-endian) clippy -debug -dist doc (-llvm-libunwind) -lto rust-analyzer rust-src rustfmt -system-llvm -test verify-sig" ABI_X86="-32 (64) (-x32)" CPU_FLAGS_X86="sse2" LLVM_SLOT="(20)" LLVM_TARGETS="-AArch64 -AMDGPU -ARC -ARM -AVR -BPF -CSKY -DirectX -Hexagon -Lanai -LoongArch -M68k -MSP430 -Mips -NVPTX -PowerPC -RISCV -SPIRV -Sparc -SystemZ -VE WebAssembly (X86) -XCore -Xtensa" RUST_SYSROOTS="-bpf wasm"
    >=sys-libs/zlib-1.3.1[abi_x86_32(-)?,abi_x86_64(-)?,abi_x86_x32(-)?,abi_mips_n32(-)?,abi_mips_n64(-)?,abi_mips_o32(-)?,abi_s390_32(-)?,abi_s390_64(-)?,minizip] (>=sys-libs/zlib-1.3.1[abi_x86_64(-),minizip]) required by (virtual/minizip-1.3.1:0/1::gentoo, installed) USE="-static-libs" ABI_X86="-32 (64) (-x32)"
    sys-libs/zlib:0/1= required by (dev-lang/rust-1.80.1-r101:1.80.1/1.80.1::gentoo, installed) USE="(-big-endian) clippy -debug -dist doc (-llvm-libunwind) -lto miri nightly -parallel-compiler rust-analyzer rust-src rustfmt -system-llvm -test verify-sig wasm" ABI_X86="-32 (64) (-x32)" CPU_FLAGS_X86="sse2" LLVM_SLOT="(18)" LLVM_TARGETS="-AArch64 -AMDGPU -ARC -ARM -AVR -BPF -CSKY -DirectX -Hexagon -Lanai -LoongArch -M68k -MSP430 -Mips -NVPTX -PowerPC -RISCV -SPIRV -Sparc -SystemZ -VE WebAssembly (X86) -XCore -Xtensa"
    sys-libs/zlib:0/1= required by (dev-lang/rust-1.82.0-r103:1.82.0/1.82.0::gentoo, installed) USE="(-big-endian) clippy -debug -dist doc (-llvm-libunwind) -lto miri nightly -parallel-compiler rust-analyzer rust-src rustfmt -system-llvm -test verify-sig wasm" ABI_X86="-32 (64) (-x32)" CPU_FLAGS_X86="sse2" LLVM_SLOT="(19)" LLVM_TARGETS="-AArch64 -AMDGPU -ARC -ARM -AVR -BPF -CSKY -DirectX -Hexagon -Lanai -LoongArch -M68k -MSP430 -Mips -NVPTX -PowerPC -RISCV -SPIRV -Sparc -SystemZ -VE WebAssembly (X86) -XCore -Xtensa"
    sys-libs/zlib:0/1= required by (dev-lang/rust-1.84.1-r2:1.84.1/1.84.1::gentoo, installed) USE="(-big-endian) clippy -debug -dist doc (-llvm-libunwind) -lto miri nightly -parallel-compiler rust-analyzer rust-src rustfmt -system-llvm -test verify-sig wasm" ABI_X86="-32 (64) (-x32)" CPU_FLAGS_X86="sse2" LLVM_SLOT="(19)" LLVM_TARGETS="-AArch64 -AMDGPU -ARC -ARM -AVR -BPF -CSKY -DirectX -Hexagon -Lanai -LoongArch -M68k -MSP430 -Mips -NVPTX -PowerPC -RISCV -SPIRV -Sparc -SystemZ -VE WebAssembly (X86) -XCore -Xtensa"
    sys-libs/zlib:0/1= required by (dev-lang/rust-1.91.0:1.91.0/1.91.0::gentoo, installed) USE="(-big-endian) clippy -debug -dist doc (-llvm-libunwind) -lto rust-analyzer rust-src rustfmt -system-llvm -test verify-sig" ABI_X86="-32 (64) (-x32)" CPU_FLAGS_X86="sse2" LLVM_SLOT="(21)" LLVM_TARGETS="-AArch64 -AMDGPU -ARC -ARM -AVR -BPF -CSKY -DirectX -Hexagon -Lanai -LoongArch -M68k -MSP430 -Mips -NVPTX -PowerPC -RISCV -SPIRV -Sparc -SystemZ -VE WebAssembly (X86) -XCore -Xtensa" RUST_SYSROOTS="-bpf wasm"
    sys-libs/zlib:0/1= required by (media-gfx/openvdb-11.0.0-r1:0/11.0::gentoo, installed) USE="-abi10-compat abi11-compat -abi12-compat -abi9-compat -alembic ax blosc (-cuda) -doc -examples -jpeg -nanovdb -numpy -openexr -png -python -static-libs -test -utils zlib" ABI_X86="(64)" CPU_FLAGS_X86="avx sse4_2" LLVM_SLOT="15" PYTHON_SINGLE_TARGET="-python3_11 -python3_12"
    sys-libs/zlib:0/1=[abi_x86_64(-)] required by (llvm-core/llvm-19.1.7:19/19.1::gentoo, installed) USE="binutils-plugin -debug (-debuginfod) doc -exegesis -libedit -libffi -test verify-sig -xml z3 zstd" ABI_X86="-32 (64) (-x32)" LLVM_TARGETS="(AArch64) (AMDGPU) -ARC (ARM) (AVR) (BPF) -CSKY -DirectX (Hexagon) (Lanai) (LoongArch) -M68k (MSP430) (Mips) (NVPTX) (PowerPC) (RISCV) SPIRV (Sparc) (SystemZ) (VE) (WebAssembly) (X86) (XCore) -Xtensa"
    sys-libs/zlib:0/1= required by (dev-lang/rust-1.83.0-r3:1.83.0/1.83.0::gentoo, installed) USE="(-big-endian) clippy -debug -dist doc (-llvm-libunwind) -lto miri nightly -parallel-compiler rust-analyzer rust-src rustfmt -system-llvm -test verify-sig wasm" ABI_X86="-32 (64) (-x32)" CPU_FLAGS_X86="sse2" LLVM_SLOT="(19)" LLVM_TARGETS="-AArch64 -AMDGPU -ARC -ARM -AVR -BPF -CSKY -DirectX -Hexagon -Lanai -LoongArch -M68k -MSP430 -Mips -NVPTX -PowerPC -RISCV -SPIRV -Sparc -SystemZ -VE WebAssembly (X86) -XCore -Xtensa"
    >=sys-libs/zlib-1.2.13:0/1=[abi_x86_64(-)] required by (dev-db/mysql-connector-c-8.0.36-1:0/21::gentoo, installed) USE="-ldap -static-libs" ABI_X86="-32 (64) (-x32)"
    >=sys-libs/zlib-1.1.3:0/1= required by (dev-lang/python-2.7.18_p16-r2:2.7/2.7::gentoo, installed) USE="(-berkdb) -bluetooth -build -examples -gdbm -ncurses -readline -sqlite -ssl -tk -valgrind verify-sig -wininst -xml" ABI_X86="(64)"

  (sys-libs/zlib-ng-2.3.2:0/0::gentoo, installed) pulled in by
    sys-libs/zlib-ng[abi_x86_32(-)?,abi_x86_64(-)?,abi_x86_x32(-)?,abi_mips_n32(-)?,abi_mips_n64(-)?,abi_mips_o32(-)?,abi_s390_32(-)?,abi_s390_64(-)?] (sys-libs/zlib-ng[abi_x86_64(-)]) required by (sys-libs/minizip-ng-4.0.10-r1:0/4::gentoo, installed) USE="-compat -lzma -openssl -test -zstd" ABI_X86="-32 (64) (-x32)"

which shows much less packages not yet rebuild.

Two ::mv packages ebuild need replacement with virtual/zlib-ng.

Some corner cases may occur at final stage, no really worried through.

Thks 4 ur attention, interest & support.

logrusx · Post by **logrusx** » Fri Jan 09, 2026 7:18 pm

You need to find the offending packages. See my work flow above.
The emerge -pvc part was to identify packages that still depended on sys-libs/zlib and then rebuild them.
You might be able to identify them gripping the pkg db, but I can't help you with that. If you go that route you should know how our find out yourself.

Ultimately, packages like chromium are incompatible and cannot be moved to zlib-ng atm.

Best Regards,
Georgi

CaptainBlood · Post by **CaptainBlood** » Fri Jan 09, 2026 7:59 pm

logrusx wrote:Ultimately, packages like chromium are incompatible and cannot be moved to zlib-ng atm.

Lucky me, not installed here.

Thks 4 ur attention, interest & support.

logrusx · Post by **logrusx** » Sat Jan 10, 2026 5:51 pm

[quote="CaptainBlood"]
I decided to follow Hu's advice, ie to rebuild packages shown as requiring sys-libs/zlib but the long lasting building ones:
This now brings the following:

Code: Select all

emerge -p -uvDU @world --exclude zig
[/quote]

You have all the rusts!?

Best Regards,
Georgi

saboya · Post by **saboya** » Sat Jan 10, 2026 6:04 pm

Having a similar issue here. If I just try to emerge sys-libs/zlib-ng[compat], portage doesn't let me:

Code: Select all

# emerge -1av sys-libs/zlib-ng

These are the packages that would be merged, in order:

Calculating dependencies... done!
Dependency resolution took 1.94 s (backtrack: 0/20).

[ebuild  N     ] sys-libs/zlib-ng-2.3.2::gentoo  USE="compat -static-libs -test" ABI_X86="32 (64) (-x32)" CPU_FLAGS_X86="avx2 avx512_vnni avx512f pclmul sse2 sse4_1 sse4_2 ssse3 vpclmulqdq" 2.390 KiB
[blocks B      ] sys-libs/zlib ("sys-libs/zlib" is soft blocking sys-libs/zlib-ng-2.3.2)
[blocks B      ] sys-libs/zlib-ng[compat] ("sys-libs/zlib-ng[compat]" is soft blocking sys-libs/zlib-1.3.1-r1)

Total: 1 package (1 new), Size of downloads: 2.390 KiB
Conflict: 2 blocks (2 unsatisfied)

 * Error: The above package list contains packages which cannot be
 * installed at the same time on the same system.

  (sys-libs/zlib-1.3.1-r1:0/1::gentoo, installed) pulled in by
    sys-libs/zlib:0/1= required by (sys-apps/util-linux-2.41.2:0/0::gentoo, installed) USE="cramfs hardlink logger ncurses nls pam readline su suid systemd udev (unicode) -audit -build -caps -cryptsetup -fdformat -kill -magic -python (-rtas) (-selinux) -slang -static-libs -test -tty-helpers -uuidd -verify-sig" ABI_X86="32 (64) (-x32)" PYTHON_TARGETS="python3_13 -python3_11 -python3_12 -python3_14"
    sys-libs/zlib:0/1= required by (net-p2p/transmission-4.0.6-r6:0/0::gentoo, installed) USE="appindicator gtk nls qt6 systemd -cli -debug -mbedtls -test" ABI_X86="(64)"
    sys-libs/zlib:0/1= required by (gnome-extra/evolution-data-server-3.56.2-r1:0/64-11-21-4-3-27-2-27-4-0::gentoo, installed) USE="gtk introspection sound vala weather -berkdb -gnome-online-accounts -gtk-doc -kerberos -ldap -oauth-gtk3 -oauth-gtk4 -test" ABI_X86="(64)"
    sys-libs/zlib:0/1= required by (media-libs/openjpeg-2.5.3-r1:2/7::gentoo, installed) USE="-doc -test" ABI_X86="32 (64) (-x32)"
    >=sys-libs/zlib-1.3.1[abi_x86_32(-)?,abi_x86_64(-)?,abi_x86_x32(-)?,abi_mips_n32(-)?,abi_mips_n64(-)?,abi_mips_o32(-)?,abi_s390_32(-)?,abi_s390_64(-)?,static-libs?] (>=sys-libs/zlib-1.3.1[abi_x86_32(-),abi_x86_64(-)]) required by (virtual/zlib-1.3.1-r1:0/1::gentoo, installed) USE="-static-libs" ABI_X86="32 (64) (-x32)"
    sys-libs/zlib:0/1=[abi_x86_32(-),abi_x86_64(-)] required by (dev-db/sqlite-3.50.4:3/3::gentoo, installed) USE="icu readline -debug -doc -secure-delete -static-libs -tcl -test -tools" ABI_X86="32 (64) (-x32)"
    >=sys-libs/zlib-1.2.8-r1:0/1=[abi_x86_32(-),abi_x86_64(-)] required by (x11-libs/libpciaccess-0.18.1:0/0::gentoo, installed) USE="zlib" ABI_X86="32 (64) (-x32)"
    sys-libs/zlib:0/1= required by (app-portage/portage-utils-0.97:0/0::gentoo, installed) USE="openmp qmanifest -static" ABI_X86="(64)"
    sys-libs/zlib:0/1= required by (app-admin/sudo-1.9.17_p2:0/0::gentoo, installed) USE="nls pam secure-path sendmail ssl -gcrypt -ldap -offensive -sasl (-selinux) -skey -sssd -verify-sig" ABI_X86="(64)"
    >=sys-libs/zlib-1.2.8-r1:0/1=[abi_x86_32(-),abi_x86_64(-)] required by (sys-libs/cracklib-2.10.3:0/0::gentoo, installed) USE="nls zlib -debug -python (-split-usr) -static-libs -test" ABI_X86="32 (64) (-x32)" PYTHON_TARGETS="python3_13 -python3_11 -python3_12"

  (sys-libs/zlib-ng-2.3.2:0/0::gentoo, ebuild scheduled for merge) pulled in by
    sys-libs/zlib-ng


For more information about Blocked Packages, please refer to the following
section of the Gentoo Linux x86 Handbook (architecture is irrelevant):

https://wiki.gentoo.org/wiki/Handbook:X86/Working/Portage#Blocked_packages

If I add all of those packages manually on the same emerge, it does allow me to continue:

Code: Select all

# emerge -1av sudo portage-utils sqlite util-linux evolution-data-server transmission openjpeg cracklib sys-libs/zlib-ng libpciaccess

These are the packages that would be merged, in order:

Calculating dependencies... done!
Dependency resolution took 2.73 s (backtrack: 0/20).

[ebuild  N     ] sys-libs/zlib-ng-2.3.2::gentoo  USE="compat -static-libs -test" ABI_X86="32 (64) (-x32)" CPU_FLAGS_X86="avx2 avx512_vnni avx512f pclmul sse2 sse4_1 sse4_2 ssse3 vpclmulqdq" 2.390 KiB
[uninstall     ] sys-libs/zlib-1.3.1-r1:0/1::gentoo  USE="minizip -static-libs -verify-sig" ABI_X86="32 (64) (-x32)"
[blocks b      ] sys-libs/zlib ("sys-libs/zlib" is soft blocking sys-libs/zlib-ng-2.3.2)
[blocks b      ] sys-libs/zlib-ng[compat] ("sys-libs/zlib-ng[compat]" is soft blocking sys-libs/zlib-1.3.1-r1)
[ebuild   R    ] dev-db/sqlite-3.50.4:3::gentoo  USE="icu readline -debug -doc -secure-delete -static-libs -tcl -test -tools" ABI_X86="32 (64) (-x32)" 0 KiB
[ebuild   R    ] sys-libs/cracklib-2.10.3::gentoo  USE="nls zlib -debug -python (-split-usr) -static-libs -test" ABI_X86="32 (64) (-x32)" PYTHON_TARGETS="python3_13 -python3_11 -python3_12" 0 KiB
[ebuild   R    ] app-portage/portage-utils-0.97::gentoo  USE="openmp qmanifest -static" 0 KiB
[ebuild   R    ] media-libs/openjpeg-2.5.3-r1:2/7::gentoo  USE="-doc -test" ABI_X86="32 (64) (-x32)" 0 KiB
[ebuild   R    ] sys-apps/util-linux-2.41.2::gentoo  USE="cramfs hardlink logger ncurses nls pam readline su suid systemd udev (unicode) -audit -build -caps -cryptsetup -fdformat -kill -magic -python (-rtas) (-selinux) -slang -static-libs -test -tty-helpers -uuidd -verify-sig" ABI_X86="32 (64) (-x32)" PYTHON_TARGETS="python3_13 -python3_11 -python3_12 -python3_14" 0 KiB
[ebuild   R    ] x11-libs/libpciaccess-0.18.1::gentoo  USE="zlib" ABI_X86="32 (64) (-x32)" 0 KiB
[ebuild   R    ] app-admin/sudo-1.9.17_p2::gentoo  USE="nls pam secure-path sendmail ssl -gcrypt -ldap -offensive -sasl (-selinux) -skey -sssd -verify-sig" 0 KiB
[ebuild   R    ] net-p2p/transmission-4.0.6-r6::gentoo  USE="appindicator gtk nls qt6 systemd -cli -debug -mbedtls -test" 0 KiB
[ebuild   R    ] gnome-extra/evolution-data-server-3.56.2-r1:0/64-11-21-4-3-27-2-27-4-0::gentoo  USE="gtk introspection sound vala weather -berkdb -gnome-online-accounts -gtk-doc -kerberos -ldap -oauth-gtk3 -oauth-gtk4 -test" 0 KiB

Total: 10 packages (1 new, 9 reinstalls, 1 uninstall), Size of downloads: 2.390 KiB
Conflict: 2 blocks (all satisfied)

Would you like to merge these packages? [Yes/No]

trubicoid · Post by **trubicoid** » Mon Jan 12, 2026 8:28 am

saboya wrote:Having a similar issue here. If I just try to emerge sys-libs/zlib-ng[compat], portage doesn't let me:

Code: Select all

# emerge -1av sys-libs/zlib-ng

These are the packages that would be merged, in order:

Calculating dependencies... done!
Dependency resolution took 1.94 s (backtrack: 0/20).

[ebuild  N     ] sys-libs/zlib-ng-2.3.2::gentoo  USE="compat -static-libs -test" ABI_X86="32 (64) (-x32)" CPU_FLAGS_X86="avx2 avx512_vnni avx512f pclmul sse2 sse4_1 sse4_2 ssse3 vpclmulqdq" 2.390 KiB
[blocks B      ] sys-libs/zlib ("sys-libs/zlib" is soft blocking sys-libs/zlib-ng-2.3.2)
[blocks B      ] sys-libs/zlib-ng[compat] ("sys-libs/zlib-ng[compat]" is soft blocking sys-libs/zlib-1.3.1-r1)

Total: 1 package (1 new), Size of downloads: 2.390 KiB
Conflict: 2 blocks (2 unsatisfied)

 * Error: The above package list contains packages which cannot be
 * installed at the same time on the same system.

  (sys-libs/zlib-1.3.1-r1:0/1::gentoo, installed) pulled in by
    sys-libs/zlib:0/1= required by (sys-apps/util-linux-2.41.2:0/0::gentoo, installed) USE="cramfs hardlink logger ncurses nls pam readline su suid systemd udev (unicode) -audit -build -caps -cryptsetup -fdformat -kill -magic -python (-rtas) (-selinux) -slang -static-libs -test -tty-helpers -uuidd -verify-sig" ABI_X86="32 (64) (-x32)" PYTHON_TARGETS="python3_13 -python3_11 -python3_12 -python3_14"
    sys-libs/zlib:0/1= required by (net-p2p/transmission-4.0.6-r6:0/0::gentoo, installed) USE="appindicator gtk nls qt6 systemd -cli -debug -mbedtls -test" ABI_X86="(64)"
    sys-libs/zlib:0/1= required by (gnome-extra/evolution-data-server-3.56.2-r1:0/64-11-21-4-3-27-2-27-4-0::gentoo, installed) USE="gtk introspection sound vala weather -berkdb -gnome-online-accounts -gtk-doc -kerberos -ldap -oauth-gtk3 -oauth-gtk4 -test" ABI_X86="(64)"
    sys-libs/zlib:0/1= required by (media-libs/openjpeg-2.5.3-r1:2/7::gentoo, installed) USE="-doc -test" ABI_X86="32 (64) (-x32)"
    >=sys-libs/zlib-1.3.1[abi_x86_32(-)?,abi_x86_64(-)?,abi_x86_x32(-)?,abi_mips_n32(-)?,abi_mips_n64(-)?,abi_mips_o32(-)?,abi_s390_32(-)?,abi_s390_64(-)?,static-libs?] (>=sys-libs/zlib-1.3.1[abi_x86_32(-),abi_x86_64(-)]) required by (virtual/zlib-1.3.1-r1:0/1::gentoo, installed) USE="-static-libs" ABI_X86="32 (64) (-x32)"
    sys-libs/zlib:0/1=[abi_x86_32(-),abi_x86_64(-)] required by (dev-db/sqlite-3.50.4:3/3::gentoo, installed) USE="icu readline -debug -doc -secure-delete -static-libs -tcl -test -tools" ABI_X86="32 (64) (-x32)"
    >=sys-libs/zlib-1.2.8-r1:0/1=[abi_x86_32(-),abi_x86_64(-)] required by (x11-libs/libpciaccess-0.18.1:0/0::gentoo, installed) USE="zlib" ABI_X86="32 (64) (-x32)"
    sys-libs/zlib:0/1= required by (app-portage/portage-utils-0.97:0/0::gentoo, installed) USE="openmp qmanifest -static" ABI_X86="(64)"
    sys-libs/zlib:0/1= required by (app-admin/sudo-1.9.17_p2:0/0::gentoo, installed) USE="nls pam secure-path sendmail ssl -gcrypt -ldap -offensive -sasl (-selinux) -skey -sssd -verify-sig" ABI_X86="(64)"
    >=sys-libs/zlib-1.2.8-r1:0/1=[abi_x86_32(-),abi_x86_64(-)] required by (sys-libs/cracklib-2.10.3:0/0::gentoo, installed) USE="nls zlib -debug -python (-split-usr) -static-libs -test" ABI_X86="32 (64) (-x32)" PYTHON_TARGETS="python3_13 -python3_11 -python3_12"

  (sys-libs/zlib-ng-2.3.2:0/0::gentoo, ebuild scheduled for merge) pulled in by
    sys-libs/zlib-ng


For more information about Blocked Packages, please refer to the following
section of the Gentoo Linux x86 Handbook (architecture is irrelevant):

https://wiki.gentoo.org/wiki/Handbook:X86/Working/Portage#Blocked_packages

If I add all of those packages manually on the same emerge, it does allow me to continue:

Code: Select all

# emerge -1av sudo portage-utils sqlite util-linux evolution-data-server transmission openjpeg cracklib sys-libs/zlib-ng libpciaccess

These are the packages that would be merged, in order:

Calculating dependencies... done!
Dependency resolution took 2.73 s (backtrack: 0/20).

[ebuild  N     ] sys-libs/zlib-ng-2.3.2::gentoo  USE="compat -static-libs -test" ABI_X86="32 (64) (-x32)" CPU_FLAGS_X86="avx2 avx512_vnni avx512f pclmul sse2 sse4_1 sse4_2 ssse3 vpclmulqdq" 2.390 KiB
[uninstall     ] sys-libs/zlib-1.3.1-r1:0/1::gentoo  USE="minizip -static-libs -verify-sig" ABI_X86="32 (64) (-x32)"
[blocks b      ] sys-libs/zlib ("sys-libs/zlib" is soft blocking sys-libs/zlib-ng-2.3.2)
[blocks b      ] sys-libs/zlib-ng[compat] ("sys-libs/zlib-ng[compat]" is soft blocking sys-libs/zlib-1.3.1-r1)
[ebuild   R    ] dev-db/sqlite-3.50.4:3::gentoo  USE="icu readline -debug -doc -secure-delete -static-libs -tcl -test -tools" ABI_X86="32 (64) (-x32)" 0 KiB
[ebuild   R    ] sys-libs/cracklib-2.10.3::gentoo  USE="nls zlib -debug -python (-split-usr) -static-libs -test" ABI_X86="32 (64) (-x32)" PYTHON_TARGETS="python3_13 -python3_11 -python3_12" 0 KiB
[ebuild   R    ] app-portage/portage-utils-0.97::gentoo  USE="openmp qmanifest -static" 0 KiB
[ebuild   R    ] media-libs/openjpeg-2.5.3-r1:2/7::gentoo  USE="-doc -test" ABI_X86="32 (64) (-x32)" 0 KiB
[ebuild   R    ] sys-apps/util-linux-2.41.2::gentoo  USE="cramfs hardlink logger ncurses nls pam readline su suid systemd udev (unicode) -audit -build -caps -cryptsetup -fdformat -kill -magic -python (-rtas) (-selinux) -slang -static-libs -test -tty-helpers -uuidd -verify-sig" ABI_X86="32 (64) (-x32)" PYTHON_TARGETS="python3_13 -python3_11 -python3_12 -python3_14" 0 KiB
[ebuild   R    ] x11-libs/libpciaccess-0.18.1::gentoo  USE="zlib" ABI_X86="32 (64) (-x32)" 0 KiB
[ebuild   R    ] app-admin/sudo-1.9.17_p2::gentoo  USE="nls pam secure-path sendmail ssl -gcrypt -ldap -offensive -sasl (-selinux) -skey -sssd -verify-sig" 0 KiB
[ebuild   R    ] net-p2p/transmission-4.0.6-r6::gentoo  USE="appindicator gtk nls qt6 systemd -cli -debug -mbedtls -test" 0 KiB
[ebuild   R    ] gnome-extra/evolution-data-server-3.56.2-r1:0/64-11-21-4-3-27-2-27-4-0::gentoo  USE="gtk introspection sound vala weather -berkdb -gnome-online-accounts -gtk-doc -kerberos -ldap -oauth-gtk3 -oauth-gtk4 -test" 0 KiB

Total: 10 packages (1 new, 9 reinstalls, 1 uninstall), Size of downloads: 2.390 KiB
Conflict: 2 blocks (all satisfied)

Would you like to merge these packages? [Yes/No]

It might help to do:

1. emerge -1av virtual/zlib
2. emerge -1av the offending packages, but without zlib-ng
3. emerge -av zlib-ng

saboya · Post by **saboya** » Mon Jan 12, 2026 10:36 am

trubicoid wrote: It might help to do:

1. emerge -1av virtual/zlib
2. emerge -1av the offending packages, but without zlib-ng
3. emerge -av zlib-ng

Why would that be any better? Seems like the same thing with extra steps. Also, virtual/zlib is already installed.

logrusx · Post by **logrusx** » Mon Jan 12, 2026 10:45 am

saboya wrote:
trubicoid wrote: It might help to do:

1. emerge -1av virtual/zlib
2. emerge -1av the offending packages, but without zlib-ng
3. emerge -av zlib-ng
Why would that be any better? Seems like the same thing with extra steps. Also, virtual/zlib is already installed.

I thought you had resolved the issue. Your solution in your previous post should be sufficient. It's similar to what I did as well. The good thing is it's very easy to revert back. Most of the rebuilding is due to ebuilds having merged when they depended on sys-libs/zlib directly. Once you rebuild them it decouples then from the sys-libs package and you can swap the implementation simply by rebuilding the desired one.

Best Regards,
Georgi

rivera151 · Post by **rivera151** » Tue Jan 13, 2026 1:40 am

logrusx wrote:
Hu wrote:Currently, that version of net-misc/openssh should be compatible. However, if you installed it before net-*/*: update for virtual/zlib, then yours might not be. Does emerge --oneshot net-misc/openssh remove it from the output? A similar situation applies to dev-libs/libxml2.
This replay is crucial for understanding the issue. Following the link one should notice dependencies on sys-libs/zlib were replaced by dependencies virtual/zlib.

Finding all packages that directly depend on sys-libz/zlib and emerge --oneshot them should untie them from sys-libs/zlib and solve the issue. Of course some of them are already recompiled after the change but to figure out which ones specifically you need to recompile is not a trivial job. Maybe grepping /var/db/pkg but I'm not that familiar enough with its structure to provide exact solution.

EDIT:
My workflow:
emerge -pvc sys-libs/zlib

emerge --deselect some stuff

emerge -1 <the above list of packages>

enable compat on sys-libs/zlib-ng

enable compat on sys-libs/minizip-ng

emerge -1auvDU --changed-deps @world sys-libs/zlib-ng minizip-ng virtual/minizip virtual/zlib

virtual/{minizip,zlib} were the ones for which packages were conflicting, that's why I included them on the command line. At the end I'm not sure I should have.

For you it might be slightly different.

This pulled in a bit over 370 packages, ~320 of which - binary.

After some more deselecting, I managed to avoid building a few big packages like nodejs and pull in the binary ones. All the packages I deselected are ones I rarely or occasionally need. It may be different for you.

Best Regards,
Georgi

After banging my head for hours on end, this is what finally worked for me. In my case, the only thing that I had to recompile besides the packages in the list was systemd, so it wasn't too bad on time. Thanks for the help, mate!

logrusx · Post by **logrusx** » Tue Jan 13, 2026 7:56 am

rivera151 wrote:
logrusx wrote:
After banging my head for hours on end, this is what finally worked for me. In my case, the only thing that I had to recompile besides the packages in the list was systemd, so it wasn't too bad on time. Thanks for the help, mate!

You're welcome!

The list of packages depends on when you were updating your system. Not only the last time but also if the affected packages were previously updated before or after the change and which ones of them were left in a limbo after the last update.

I was also not entirely correct and I have edited my post above. Emerge would have reported only packages that were emerged with direct dependence on sys-libz/zlib. I've edited my post to reflect that.

And last but not least, this change is not mandatory at all. It's completely optional and I undertook it just out of curiosity.

People could just rebuild the packages reported by emerge -pvc virtual/zlib and they can move on with their lives. And in certain circumstances even that's not necessary, but may prove to be should a dependency conflict involving zlib and the virtual arise.

Best Regards,
Georgi

mid-kid · Post by **mid-kid** » Thu Feb 19, 2026 5:52 pm

Like posts above mention, I ran "emerge -vpc sys-libs/zlib" and re-emerged all packages that still directly depended on it. However, I still can't for the life of me get it to resolve the correct thing:

Code: Select all

PocketRocket ~ # emerge -puDU --usepkg=n --changed-deps --changed-slot @world sys-libs/zlib-ng sys-libs/minizip-ng virtual/zlib virtual/minizip

These are the packages that would be merged, in order:

Calculating dependencies  ....... done!
Dependency resolution took 15.14 s (backtrack: 0/20).

[ebuild   R    ] net-libs/nghttp3-1.9.0
[ebuild   R    ] dev-libs/boehm-gc-8.2.8
[ebuild   R    ] sys-apps/kmod-34.2
[ebuild   R    ] sys-kernel/linux-headers-6.12
[ebuild   R    ] dev-libs/gmp-6.3.0-r1  USE="-verify-sig%"
[ebuild   R    ] sys-apps/attr-2.5.2-r1
[ebuild   R    ] dev-libs/popt-1.19-r1
[ebuild   R    ] dev-build/libtool-2.5.4
[ebuild   R    ] sys-fs/eudev-3.2.14
[ebuild   R    ] dev-libs/isl-0.27
[ebuild   R    ] app-crypt/libb2-0.98.1-r3
[ebuild   R    ] sys-libs/zlib-1.3.1-r1
[ebuild   R    ] x11-libs/libXdmcp-1.1.5
[ebuild   R    ] app-arch/zstd-1.5.7-r1  USE="-verify-sig%"
[ebuild   R    ] sys-apps/sed-4.9-r1  USE="-test-full%"
[ebuild   R    ] sys-apps/file-5.46-r3
[ebuild   R    ] dev-libs/libbsd-0.11.8
[ebuild   R    ] dev-libs/libyaml-0.2.5
[ebuild   R    ] x11-libs/libfontenc-1.1.8
[ebuild   R    ] dev-libs/libnatspec-0.3.0
[ebuild   R    ] app-text/opensp-1.5.2-r10
[ebuild   R    ] dev-lang/tcl-8.6.16
[ebuild   R    ] media-libs/jbig2dec-0.20
[ebuild   R    ] dev-tcltk/expect-5.45.4-r5
[ebuild   R    ] dev-libs/elfutils-0.193-r1
[ebuild   R    ] x11-libs/libxcb-1.17.0
[ebuild   R    ] app-misc/ca-certificates-20240203.3.98
[ebuild   R    ] dev-libs/jsoncpp-1.9.6-r2
[ebuild   R    ] app-crypt/p11-kit-0.25.5
[ebuild   R    ] x11-libs/libXext-1.3.6
[ebuild   R    ] x11-apps/xprop-1.2.8
[ebuild   R    ] media-libs/libglvnd-1.7.0
[ebuild   R    ] x11-libs/libXi-1.8.2
[ebuild   R    ] x11-libs/libXrandr-1.5.4
[ebuild   R    ] x11-libs/libXmu-1.2.1
[ebuild   R    ] x11-apps/xset-1.2.5
[ebuild   R    ] media-libs/glu-9.0.3
[ebuild   R    ] dev-libs/libfmt-11.1.4
[ebuild   R    ] media-libs/freeglut-3.6.0-r1
[ebuild   R    ] sys-libs/zlib-ng-2.3.2  USE="compat*"
[ebuild   R    ] net-libs/libssh2-1.11.1  USE="-verify-sig%"
[ebuild   R    ] net-libs/llhttp-9.2.1
[ebuild   R    ] media-libs/tiff-4.7.0-r1
[ebuild   R    ] dev-libs/spdlog-1.15.3
[ebuild   R    ] sys-libs/minizip-ng-4.0.10-r1  USE="compat*"
[ebuild   R    ] app-eselect/eselect-rust-20210703
[ebuild   R    ] sys-auth/polkit-126-r2
[ebuild   R    ] media-libs/freetype-2.14.1-r1  USE="-verify-sig%"
[ebuild   R    ] x11-apps/mkfontscale-1.2.3
[ebuild   R    ] media-fonts/encodings-1.1.0
[ebuild   R    ] media-fonts/liberation-fonts-2.1.5
[ebuild   R    ] x11-libs/cairo-1.18.4-r1
[ebuild   R    ] www-client/w3m-0.5.3_p20240916
[ebuild   R    ] sys-devel/flex-2.6.4-r6
[ebuild   R    ] app-text/xmlto-0.0.28-r11
[ebuild   R    ] sys-apps/dbus-1.16.2
[ebuild   R    ] gnome-base/dconf-0.40.0
[ebuild   R    ] x11-misc/xdg-utils-1.2.1-r9
[ebuild   R    ] app-text/ghostscript-gpl-10.06.0
[ebuild   R    ] app-text/doxygen-1.13.2
[blocks B      ] sys-libs/zlib-ng[compat] ("sys-libs/zlib-ng[compat]" is soft blocking sys-libs/zlib-1.3.1-r1)
[blocks B      ] sys-libs/zlib ("sys-libs/zlib" is soft blocking sys-libs/zlib-ng-2.3.2)
[blocks B      ] sys-libs/zlib[minizip] ("sys-libs/zlib[minizip]" is soft blocking sys-libs/minizip-ng-4.0.10-r1)

 * Error: The above package list contains packages which cannot be
 * installed at the same time on the same system.

  (sys-libs/zlib-ng-2.3.2:0/0::gentoo, ebuild scheduled for merge) pulled in by
    sys-libs/zlib-ng
    >=sys-libs/zlib-ng-1.3.1:= required by (games-emulation/dolphin-2509-1:0/0::gentoo, installed) USE="alsa evdev gui vulkan -bluetooth -discord-presence -doc -egl -ffmpeg -llvm -log-mgba -profile -pulseaudio -sdl (-systemd) -telemetry -test -upnp" ABI_X86="(64)" LLVM_SLOT="20 -18 -19"
    >=sys-libs/zlib-ng-1.3.1:0/0= required by (games-emulation/dolphin-2509-1:0/0::gentoo, installed) USE="alsa evdev gui vulkan -bluetooth -discord-presence -doc -egl -ffmpeg -llvm -log -mgba -profile -pulseaudio -sdl (-systemd) -telemetry -test -upnp" ABI_X86="(64)" LLVM_SLOT="20 -18 -19"
    sys-libs/zlib-ng[abi_x86_32(-)?,abi_x86_64(-)?,abi_x86_x32(-)?,abi_mips_n32(-)?,abi_mips_n64(-)?,abi_mips_o32(-)?,abi_s390_32(-)?,abi_s390_64(-)?] (sys-libs/zlib-ng[abi_x86_64(-)]) required by (sys-libs/minizip-ng-4.0.10-r1:0/4::gentoo, ebuild scheduled for merge) USE="compat -lzma -openssl -test -zstd" ABI_X86="(64) -32 (-x32)"

  (sys-libs/zlib-1.3.1-r1:0/1::gentoo, ebuild scheduled for merge) pulled in by
    >=sys-libs/zlib-1.3.1[abi_x86_32(-)?,abi_x86_64(-)?,abi_x86_x32(-)?,abi_mips_n32(-)?,abi_mips_n64(-)?,abi_mips_o32(-)?,abi_s390_32(-)?,abi_s390_64(-)?,static-libs?] (>=sys-libs/zlib-1.3.1[abi_x86_32(-),abi_x86_64(-)]) required by (virtual/zlib-1.3.1-r1-2:0/1::gentoo, installed) USE="-static-libs" ABI_X86="32 (64) (-x32)"
    >=sys-libs/zlib-1.3.1[abi_x86_32(-)?,abi_x86_64(-)?,abi_x86_x32(-)?,abi_mips_n32(-)?,abi_mips_n64(-)?,abi_mips_o32(-)?,abi_s390_32(-)?,abi_s390_64(-)?,minizip] (>=sys-libs/zlib-1.3.1[abi_x86_64(-),minizip]) required by (virtual/minizip-1.3.1-2:0/1::gentoo, installed) USE="-static-libs" ABI_X86="(64) -32 (-x32)"

  (sys-libs/minizip-ng-4.0.10-r1:0/4::gentoo, ebuild scheduled for merge) pulled in by
    sys-libs/minizip-ng:0/4= required by (media-libs/opencolorio-2.4.2-1:0/2.4::gentoo, installed) USE="opengl -apps -doc -python -test" ABI_X86="(64)" CPU_FLAGS_X86="avx avx2 f16c sse2 sse3 sse4_1 sse4_2 ssse3 -avx512f" PYTHON_SINGLE_TARGET="python3_13 -python3_11 -python3_12"
    >=sys-libs/minizip-ng-4.0.4:= required by (games-emulation/dolphin-2509-1:0/0::gentoo, installed) USE="alsa evdev gui vulkan -bluetooth -discord-presence -doc -egl -ffmpeg -llvm -log -mgba -profile -pulseaudio -sdl (-systemd) -telemetry -test -upnp" ABI_X86="(64)" LLVM_SLOT="20 -18 -19"
    sys-libs/minizip-ng:= required by (media-libs/opencolorio-2.4.2-1:0/2.4::gentoo, installed) USE="opengl -apps -doc -python -test" ABI_X86="(64)" CPU_FLAGS_X86="avx avx2 f16c sse2 sse3 sse4_1 sse4_2 ssse3 -avx512f" PYTHON_SINGLE_TARGET="python3_13 -python3_11 -python3_12"
    >=sys-libs/minizip-ng-4.0.4:0/4= required by (games-emulation/dolphin-2509-1:0/0::gentoo, installed) USE="alsa evdev gui vulkan -bluetooth -discord-presence -doc -egl -ffmpeg -llvm -log -mgba -profile -pulseaudio -sdl (-systemd) -telemetry -test -upnp" ABI_X86="(64)" LLVM_SLOT="20 -18 -19"
    sys-libs/minizip-ng


For more information about Blocked Packages, please refer to the following
section of the Gentoo Linux x86 Handbook (architecture is irrelevant):

https://wiki.gentoo.org/wiki/Handbook:X86/Working/Portage\#Blocked_packages

The only things that depend directly on sys-libs/zlib are the virtuals, but I've already re-emerged those, and made sure that they have the OR-depend on zlib-ng. Still, it's not working out. I've tried without "@world" and with "--ignore-world", and a few other different combinations of flags like "--complete-graph", but I'm out of ideas.

Anyone have any idea what's happening?

EDIT: It turns out I was missing abi_x86_32 on sys-libs/zlib-ng and sys-libs/minizip-ng, as it was being requested on virtual/zlib...

logrusx · Post by **logrusx** » Thu Feb 19, 2026 6:41 pm

I've reverted back since. I don't think this migration is worth except in very specific cases.

Thankfully the revert is very easy. Just emerge -1 sys-libs/zlib.

Best Regards,
Georgi