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fix(flutter): stop shipping LTO bitcode in the iOS static lib (pub.dev 256MiB) - #196
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…v 256MiB) A cargo staticlib never goes through a link step, so the workspace's fat-LTO (lto = true) only makes cargo pass -C embed-bitcode=yes: every codegen unit embeds its full LLVM bitcode (.llvmbc on ELF, __LLVM,__bitcode on Mach-O) and it stays in the .a forever. On the v0.5.0 xcframework each slice hit ~128MB (bitcode ~80% + debug symbols); the two slices pushed the uncompressed pub package past the 256MiB limit and pub.dev rejected the release. - new [profile.ios-release] (inherits release, lto = false); the iOS build script switches to it, keeping opt-level=z / codegen-units=1 / strip - the script additionally runs strip -Sx (debug + local symbols; globals stay for the podspec force_load) and bitcode_strip -r as a guard - measured on the Linux staticlib (same mechanism): 138.4MB -> 66.5MB; per-member .llvmbc gone (16.9MB in the largest single object) - CFBundleShortVersionString in the generated Info.plist was hardcoded 0.2.0; now read from Cargo.toml - flutter CHANGELOG gains the missing 0.5.0 entry (pub validation warning) Desktop .a artifacts on the GitHub Release keep the fat profile for now; nothing links them at CI time and nothing limits their size.
Xcode 26.6's bitcode_strip fails on the LTO-off archive with 'internal link edit command failed' (the tool has been dead weight since Apple removed bitcode support in Xcode 14). Its only job was guarding against a profile regression; a 64MiB size gate does that more directly and maps onto the pub.dev package limit — a healthy slice is ~15-30MB, an LTO/bitcode regression lands near 128MB.
This was referenced Sep 28, 2026
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Problem
The v0.5.0 release failed on Publish Flutter to pub.dev:
Uncompressed package archive is too large (size > 268435456). Every other release target (crates.io, npm, PyPI, Maven Central, GitHub Release) succeeded.Root cause: a cargo
staticlibnever goes through a link step, so the workspace'slto = trueonly makes cargo pass-C embed-bitcode=yes— every codegen unit embeds its full LLVM bitcode (.llvmbcon ELF,__LLVM,__bitcodeon Mach-O) and it stays in the.aforever. The 0.5.0 iOS xcframework slices hit ~128MB each (bitcode ≈80% + debug symbols), pushing the unpacked pub package past 256MiB. 0.3.0 (92MB/slice) had just squeaked under.Fix
[profile.ios-release](inheritsrelease,lto = false) — used only byscripts/build-ios-xcframework.sh;opt-level = "z",codegen-units = 1andstripare unchanged, and every other target keeps fat-LTO.strip -Sx(debug + local symbols; global symbols stay — the podspecforce_loadresolves against them) andxcrun bitcode_strip -ras a belt-and-braces guard.CFBundleShortVersionStringin the generated Info.plist was hardcoded0.2.0; now read fromCargo.toml.bindings/flutter/CHANGELOG.mdgains the missing0.5.0entry (pub validation warning, and pub.dev renders it on the package page).Validation
cargo build --profile ios-release --target x86_64-unknown-linux-gnu -p aimux-ffi):strip -Sx.llvmbcsections: 0 (was 16.9MB inside the single largest object)RUSTFLAGS="-C lto=off"does not work (cargo orders its own profile flag after user RUSTFLAGS) — hence the dedicated profile.Flutter bindingjob (ci.yml) runs this script on macOS withflutter test, so the PR checks exercise the real Apple toolchain end to end.Release follow-up
After merge:
workflow_dispatchthe Release workflow with onlyflutterenabled to re-publish the 0.5.0 package (android + ios artifacts rebuild with this fix; GitHub Release assets stay as-is).