https://blogs.gentoo.org/ago/2020/07/04/gentoo-tinderbox/ Issue: sys-process/below-0.5.0 fails to compile (lto). Discovered on: amd64 (internal ref: lto_tinderbox) NOTE: This machine uses lto with CFLAGS=-flto -Werror=odr -Werror=lto-type-mismatch -Werror=strict-aliasing Here is a bit of explanation: -Werror=lto-type-mismatch: User to find possible runtime issues in packages. It likely means the package is unsafe to build & use with LTO. For projects using the same identifier but with different types across different files, they must be fixed to be consistent across the codebase. -Werror=odr: Used to find possible runtime issues in packages. These bugs are a problem anyway but may be even worse when combined with LTO. C++ code must comply with the One Definition Rule (ODR) - see https://en.cppreference.com/w/cpp/language/definition#One_Definition_Rule. -Werror=strict-aliasing: Used to find possible runtime issues in packages. These bugs are a problem anyway but may be even worse when combined with LTO. Workarounds: - If upstream is friendly and still active, file a bug upstream. For emulators, codecs, games, or multimedia packages, it may be worth just applying a workaround instead, as upstreams sometimes aren't receptive to these bugs (VALID FOR ALL). - Use the new 'filter-lto' from flag-o-matic.eclass as it's likely to be unsafe with LTO (VALID FOR lto-type-mismatch - odr). - Fix it yourself if interested, of course (VALID FOR ALL). - Append-flags -fno-strict-aliasing (VALID FOR strict-aliasing). - Use memcpy() but a union is sometimes suitable too (VALID FOR strict-aliasing). - -fstrict-aliasing is implied by -O2, so this must be addressed in some form (VALID FOR strict-aliasing). See also: https://marc.info/?l=gentoo-dev&m=165639574126280&w=2
Created attachment 798163 [details] build.log build log and emerge --info
Error(s) that match a know pattern in addition to what has been reported in the summary: /usr/lib/gcc/x86_64-pc-linux-gnu/12.1.1/../../../../x86_64-pc-linux-gnu/bin/ld: libbpf_cargo.05371e16-cgu.0:(.text._ZN12libbpf_cargo3btf3btf3Btf3new17hdf28d994eea11771E+0x2d5): undefined reference to `libbpf_get_error' /usr/lib/gcc/x86_64-pc-linux-gnu/12.1.1/../../../../x86_64-pc-linux-gnu/bin/ld: libbpf_cargo.05371e16-cgu.0:(.text._ZN12libbpf_cargo3btf3btf3Btf3new17hdf28d994eea11771E+0x312): undefined reference to `bpf_object__btf' /usr/lib/gcc/x86_64-pc-linux-gnu/12.1.1/../../../../x86_64-pc-linux-gnu/bin/ld: libbpf_cargo.05371e16-cgu.0:(.text._ZN12libbpf_cargo3btf3btf3Btf3new17hdf28d994eea11771E+0x52f): undefined reference to `btf__set_endianness' /usr/lib/gcc/x86_64-pc-linux-gnu/12.1.1/../../../../x86_64-pc-linux-gnu/bin/ld: libbpf_cargo.05371e16-cgu.0:(.text._ZN12libbpf_cargo3btf3btf3Btf3new17hdf28d994eea11771E+0x55c): undefined reference to `btf__pointer_size' /usr/lib/gcc/x86_64-pc-linux-gnu/12.1.1/../../../../x86_64-pc-linux-gnu/bin/ld: libbpf_cargo.05371e16-cgu.0:(.text._ZN12libbpf_cargo3btf3btf3Btf3new17hdf28d994eea11771E+0x5f5): undefined reference to `btf__get_raw_data' libbpf_cargo.05371e16-cgu.0:(.text._ZN12libbpf_cargo3btf3btf3Btf3new17hdf28d994eea11771E+0x2b2): undefined reference to `bpf_object__open_mem' libbpf_cargo.05371e16-cgu.0:(.text._ZN69_$LT$libbpf_cargo..btf..btf..Btf$u20$as$u20$core..ops..drop..Drop$GT$4drop17hd8d4d12ee44a110fE+0x7): undefined reference to `bpf_object__close' libbpf_cargo.05371e16-cgu.1:(.text._ZN12libbpf_cargo3gen12get_map_name17h5015298e44c2e16fE+0x8c): undefined reference to `bpf_map__is_internal' libbpf_cargo.05371e16-cgu.1:(.text._ZN12libbpf_cargo3gen13get_prog_name17h168411c247dc50d4E+0x20): undefined reference to `bpf_program__name' libbpf_cargo.05371e16-cgu.1:(.text._ZN12libbpf_cargo3gen14map_is_datasec17h92314c3a007507d1E+0xb): undefined reference to `bpf_map__is_internal' libbpf_cargo.05371e16-cgu.1:(.text._ZN12libbpf_cargo3gen15map_is_mmapable17haa28e181a322b534E+0x3): undefined reference to `bpf_map__def' libbpf_cargo.05371e16-cgu.1:(.text._ZN12libbpf_cargo3gen15map_is_readonly17h27ffee8017b60d71E+0x23): undefined reference to `bpf_map__def' libbpf_cargo.05371e16-cgu.1:(.text._ZN12libbpf_cargo3gen15open_bpf_object17h5aadd5941c31390fE+0x222): undefined reference to `bpf_object__open_mem' libbpf_cargo.05371e16-cgu.1:(.text._ZN12libbpf_cargo3gen16get_raw_map_name17h6f71ef3adfda0a3bE+0x20): undefined reference to `bpf_map__name' libbpf_cargo.05371e16-cgu.1:(.text._ZN85_$LT$libbpf_cargo..gen..MapIter$u20$as$u20$core..iter..traits..iterator..Iterator$GT$4next17he65d9bf75a02abd7E+0x15): undefined reference to `bpf_map__next' libbpf_cargo.05371e16-cgu.1:(.text._ZN86_$LT$libbpf_cargo..gen..ProgIter$u20$as$u20$core..iter..traits..iterator..Iterator$GT$4next17h3dc48292233ccf09E+0x15): undefined reference to `bpf_program__next' error: linking with `x86_64-pc-linux-gnu-gcc` failed: exit status: 1
