From b6425d6b0e2d52075d50907d2519f18e5530945d Mon Sep 17 00:00:00 2001
From: smalis-msft <137308034+smalis-msft@users.noreply.github.com>
Date: Tue, 8 Aug 2023 18:48:43 -0400
Subject: [PATCH 1/4] Do not enable any features by default

---
 Cargo.toml | 8 +-------
 1 file changed, 1 insertion(+), 7 deletions(-)

diff --git a/Cargo.toml b/Cargo.toml
index c788b5eb0d..8cfd38fbc3 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -34,13 +34,7 @@ pin-utils = { version = "0.1.0", optional = true }
 memoffset = { version = "0.9", optional = true }
 
 [features]
-default = [
-  "acct", "aio", "dir", "env", "event", "feature", "fs",
-  "hostname", "inotify", "ioctl", "kmod", "mman", "mount", "mqueue",
-  "net", "personality", "poll", "process", "pthread", "ptrace", "quota",
-  "reboot", "resource", "sched", "signal", "socket", "term", "time",
-  "ucontext", "uio", "user", "zerocopy",
-]
+default = []
 
 acct = []
 aio = ["pin-utils"]

From 08f393e6c239b2e55f25fddd914662e2b741246c Mon Sep 17 00:00:00 2001
From: Steven Malis <stevenmalis@microsoft.com>
Date: Wed, 9 Aug 2023 10:44:44 -0400
Subject: [PATCH 2/4] Attempt to add --all-features to CI.

---
 .cirrus.yml | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/.cirrus.yml b/.cirrus.yml
index 6d5402df69..5aba3473c4 100644
--- a/.cirrus.yml
+++ b/.cirrus.yml
@@ -18,9 +18,9 @@ build: &BUILD
     - . $HOME/.cargo/env || true
     - $TOOL -Vv
     - rustc -Vv
-    - $TOOL $BUILD $ZFLAGS --target $TARGET --all-targets
-    - $TOOL doc $ZFLAGS --no-deps --target $TARGET
-    - $TOOL clippy $ZFLAGS --target $TARGET --all-targets -- $CLIPPYFLAGS
+    - $TOOL $BUILD $ZFLAGS --target $TARGET --all-targets --all-features
+    - $TOOL doc $ZFLAGS --no-deps --target $TARGET --all-features
+    - $TOOL clippy $ZFLAGS --target $TARGET --all-targets --all-features -- $CLIPPYFLAGS
     - if [ -z "$NOHACK" ]; then mkdir -p $HOME/.cargo/bin; export PATH=$HOME/.cargo/bin:$PATH; fi
     - if [ -z "$NOHACK" ]; then curl -LsSf https://github.com/taiki-e/cargo-hack/releases/latest/download/cargo-hack-${HOST:-$TARGET}.tar.gz | tar xzf - -C ~/.cargo/bin; fi
     - if [ -z "$NOHACK" ]; then $TOOL hack $ZFLAGS check --target $TARGET --each-feature; fi
@@ -30,7 +30,7 @@ test: &TEST
   << : *BUILD
   test_script:
     - . $HOME/.cargo/env || true
-    - $TOOL test --target $TARGET
+    - $TOOL test --target $TARGET --all-features
 
 # Test FreeBSD in a full VM.  Test the i686 target too, in the
 # same VM.  The binary will be built in 32-bit mode, but will execute on a
@@ -59,9 +59,9 @@ task:
   << : *TEST
   i386_test_script:
     - . $HOME/.cargo/env
-    - cargo build --target i686-unknown-freebsd
-    - cargo doc --no-deps --target i686-unknown-freebsd
-    - cargo test --target i686-unknown-freebsd
+    - cargo build --target i686-unknown-freebsd --all-features
+    - cargo doc --no-deps --target i686-unknown-freebsd --all-features
+    - cargo test --target i686-unknown-freebsd --all-features
   i386_feature_script:
     - . $HOME/.cargo/env
     - if [ -z "$NOHACK" ]; then cargo hack check --each-feature --target i686-unknown-freebsd; fi

From 5a17e30a5f319c0861feea6b5297634e7754ef6b Mon Sep 17 00:00:00 2001
From: Steven Malis <stevenmalis@microsoft.com>
Date: Fri, 11 Aug 2023 11:30:50 -0400
Subject: [PATCH 3/4] Rework unused_imports allow.

---
 src/lib.rs | 38 +++++++++++++++++++++++++++++++++++++-
 1 file changed, 37 insertions(+), 1 deletion(-)

diff --git a/src/lib.rs b/src/lib.rs
index 8649a34d44..af0c67b0f3 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -47,7 +47,43 @@
 #![recursion_limit = "500"]
 #![deny(unused)]
 #![allow(unused_macros)]
-#![cfg_attr(not(feature = "default"), allow(unused_imports))]
+#![cfg_attr(
+    not(all(
+        feature = "acct",
+        feature = "aio",
+        feature = "dir",
+        feature = "env",
+        feature = "event",
+        feature = "feature",
+        feature = "fs",
+        feature = "hostname",
+        feature = "inotify",
+        feature = "ioctl",
+        feature = "kmod",
+        feature = "mman",
+        feature = "mount",
+        feature = "mqueue",
+        feature = "net",
+        feature = "personality",
+        feature = "poll",
+        feature = "process",
+        feature = "pthread",
+        feature = "ptrace",
+        feature = "quota",
+        feature = "reboot",
+        feature = "resource",
+        feature = "sched",
+        feature = "socket",
+        feature = "signal",
+        feature = "term",
+        feature = "time",
+        feature = "ucontext",
+        feature = "uio",
+        feature = "user",
+        feature = "zerocopy",
+    )),
+    allow(unused_imports)
+)]
 #![deny(unstable_features)]
 #![deny(missing_copy_implementations)]
 #![deny(missing_debug_implementations)]

From fa71f33eee1e9a69c7383f6390b255f7256b5a85 Mon Sep 17 00:00:00 2001
From: Steven Malis <stevenmalis@microsoft.com>
Date: Fri, 11 Aug 2023 11:34:52 -0400
Subject: [PATCH 4/4] Add changelog entry.

---
 CHANGELOG.md | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 308f929025..283aa183f8 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -43,6 +43,9 @@ This project adheres to [Semantic Versioning](https://semver.org/).
   ([#1943](https://github.com/nix-rust/nix/pull/1943))
 - `nix::socket` and `nix::select` are now available on Redox.
   ([#2012](https://github.com/nix-rust/nix/pull/2012))
+- All features have been removed from the default set. Users will need to specify
+  which features they depend on in their Cargo.toml.
+  ([#2091](https://github.com/nix-rust/nix/pull/2091))
 
 ### Fixed
 - Fix: send `ETH_P_ALL` in htons format