# Large Windows binaries for Rust/Cargo **URL:** \ **Category:** Windows\ **Tags:** deployment\ **Created:** [April 26, 2020, 3:49pm UTC](https://travis-ci.community/t/large-windows-binaries-for-rust-cargo/8356 "2020-04-26T15:49:24Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![mlange-42](https://avatars.discourse-cdn.com/v4/letter/m/db5fbb/32.png) [@mlange-42](https://travis-ci.community/u/mlange-42)\ **Post date:** [April 26, 2020, 3:49pm UTC](https://travis-ci.community/t/large-windows-binaries-for-rust-cargo/8356/1 "2020-04-26T15:49:24Z")
When trying to deploy a Rust/Cargo project for Windows, I get binaries much larger then when building locally. E.g. the primary `.exe` file (`chrono-photo.exe`) is 9.4MB, compared to 3.1MB for the local build. I have no comparison for OSX and Linux binaries, as I didn’t set up these builds locally. The issue arises for the `.travis.yml` in the commit linked below, and also for other repositories: > **[mlange-42/chrono-photo](https://github.com/mlange-42/chrono-photo/tree/8ea8f74943d4cd4e7c9b27b740d5ddf38e09b812)** > > Chronophotography command line tool and library in Rust. - mlange-42/chrono-photo Is there anything I am missing, or any way to reduce binary size to what I get locally? Many thanks in advance! ---
**Author:** ![native-api](https://sea1.discourse-cdn.com/flex015/user_avatar/travis-ci.community/native-api/32/430_2.png) [@native-api](https://travis-ci.community/u/native-api)\ **Post date:** [April 27, 2020, 12:18pm UTC](https://travis-ci.community/t/large-windows-binaries-for-rust-cargo/8356/2 "2020-04-27T12:18:22Z")
[This](https://travis-ci.com/github/mlange-42/chrono-photo/jobs/323516652#L637) is a relevant-looking tell (emphasis mine): > Finished test **[unoptimized + debuginfo]** target(s) in 2m 21s ---
**Author:** ![mlange-42](https://avatars.discourse-cdn.com/v4/letter/m/db5fbb/32.png) [@mlange-42](https://travis-ci.community/u/mlange-42)\ **Post date:** [April 27, 2020, 12:48pm UTC](https://travis-ci.community/t/large-windows-binaries-for-rust-cargo/8356/3 "2020-04-27T12:48:24Z")
Many thanks for the hint. However, release builds (`cargo build --release`) go to folder `target/release`, where I take the binaries for deployment from. Builds for tests go to folder `target/debug`. Also, changing the order to execute tests before the release build did not change the excutable’s size. There is a much simpler repo with the same problem: [https://travis-ci.com/github/mlange-42/travis-test](https://travis-ci.com/github/mlange-42/travis-test) Here, Travis builds for Windows are 3.5MB, while the local (release) build is 143kB! Local test builds are 146kB, which also shows that `unoptimized` can’t be the cause of the problem. Thanks again! ---
**Author:** ![native-api](https://sea1.discourse-cdn.com/flex015/user_avatar/travis-ci.community/native-api/32/430_2.png) [@native-api](https://travis-ci.community/u/native-api)\ **Post date:** [December 13, 2020, 12:58pm UTC](https://travis-ci.community/t/large-windows-binaries-for-rust-cargo/8356/4 "2020-12-13T12:58:05Z")
In my test, both Windows and Linux builds are ~3M, so it’s not Windows-specific. They don’t have import from non-system libs and almost all the space is taken up by the `.text` section. So **my guess is they are statically linked.** According to [rust - How to generate statically linked executables? - Stack Overflow](https://stackoverflow.com/questions/31770604/how-to-generate-statically-linked-executables), this is controlled by the `.cargo/config` file: > [Since Rust 1.19](https://github.com/rust-lang/rust/blob/master/RELEASES.md#version-1190-2017-07-20), you can statically link the C runtime (CRT) to avoid this very common situation on Windows: > > > The program can’t start because VCRUNTIME140.dll is missing from your computer. Try reinstalling the program to fix this problem. > > Add this to your `.cargo/config` file, using the appropriate target triple for your platform: > > ```auto > [target.x86_64-pc-windows-msvc] > rustflags = ["-C", "target-feature=+crt-static"] > > ``` > > An alternative to editing `.cargo/config` is to pass `-C target-feature=+crt-static` to rustc by hand. > > See also: > > - [RFC](https://github.com/rust-lang/rfcs/blob/master/text/1721-crt-static.md) > - [Pull Request](https://github.com/rust-lang/rust/pull/37545) > - [Cargo config documentation](https://doc.rust-lang.org/cargo/reference/config.html)