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

Calculating dependencies ... done!
Dependency resolution took 2.45 s (backtrack: 1/20).

[ebuild  N     ] dev-lang/rust-common-1.99.0::gentoo  USE="-verify-sig" 259042 KiB
[ebuild  N     ] dev-libs/oniguruma-6.9.10:0/5::gentoo  USE="-crnl-as-line-terminator -static-libs" 957 KiB
[ebuild  NS    ] dev-lang/rust-bin-1.90.0:1.90.0::gentoo [1.94.0:1.94.0::gentoo] USE="(-big-endian) -clippy* -doc* (-prefix) -rust-analyzer -rust-src -rustfmt* -verify-sig" CPU_FLAGS_X86="sse2" LLVM_SLOT="(20%*) (-21%*)" 198242 KiB
[ebuild  NS    ] llvm-core/llvm-20.1.8:20/20.1::gentoo [22.1.1:22/22.1::gentoo] USE="binutils-plugin libffi zstd -debug (-debuginfod) -doc -exegesis -libedit -test -verify-sig -xml -z3" LLVM_TARGETS="(AArch64) (AMDGPU) (ARM) (AVR) (BPF) (Hexagon) (Lanai) (LoongArch) (MSP430) (Mips) (NVPTX) (PowerPC) (RISCV) (SPIRV) (Sparc) (SystemZ) (VE) (WebAssembly) (X86) (XCore) -ARC -CSKY -DirectX -M68k -Xtensa" 144082 KiB
[ebuild  NS    ] llvm-core/llvm-toolchain-symlinks-20-r1:20::gentoo [22:22::gentoo] USE="-multilib-symlinks -native-symlinks" 0 KiB
[ebuild  N     ] llvm-core/lld-20.1.8:20/20.1::gentoo  USE="zstd -debug -test -verify-sig" LLVM_TARGETS="(AArch64) (AMDGPU) (ARM) (AVR) (BPF) (Hexagon) (Lanai) (LoongArch) (MSP430) (Mips) (NVPTX) (PowerPC) (RISCV) (SPIRV) (Sparc) (SystemZ) (VE) (WebAssembly) (X86) (XCore) -ARC -CSKY -DirectX -M68k -Xtensa" 0 KiB
[ebuild  N     ] llvm-core/lld-toolchain-symlinks-20:20::gentoo  USE="-multilib-symlinks -native-symlinks" 0 KiB
[ebuild  N     ] dev-lang/rust-1.90.0-r1:1.90.0::gentoo  USE="lto system-llvm (-big-endian) -clippy -debug -dist -doc (-llvm-libunwind) -mrustc-bootstrap -rust-analyzer -rust-src -rustfmt -test -verify-sig" CPU_FLAGS_X86="sse2" LLVM_SLOT="(20)" LLVM_TARGETS="(X86) -AArch64 -AMDGPU -ARC -ARM -AVR -BPF -CSKY -DirectX -Hexagon -Lanai -LoongArch -M68k -MSP430 -Mips -NVPTX -PowerPC -RISCV -SPIRV -Sparc -SystemZ -VE -WebAssembly -XCore -Xtensa" RUST_SYSROOTS="-bpf -wasm" 265972 KiB

Total: 8 packages (5 new, 3 in new slots), Size of downloads: 868293 KiB