refactor: remove disable-build-script, prefer-* features

Simplifies downstream usage in libraries using docs.rs.

`prefer-*` had to be removed because I could not for the life of me get
rust-analyzer to **not** enable all Cargo features.
No matter what, it always wanted to compile ORT from source after
removing the `disable-build-script` feature. I gave up and decided
the features were not useful anyways.

Cargo.toml

@@ -21,12 +21,10 @@ strip = true
 codegen-units = 1
 
 [package.metadata.docs.rs]
-features = [ "half", "fetch-models", "copy-dylibs", "disable-build-script" ]
+features = [ "half", "fetch-models", "copy-dylibs" ]
 
 [features]
 default = [ "half", "fetch-models", "copy-dylibs" ]
-# used to prevent issues with docs.rs
-disable-build-script = []
 
 profiling = [ "widestring" ]
 
@@ -35,9 +33,6 @@ generate-bindings = [ "bindgen" ]
 copy-dylibs = []
 
 # ONNX compile flags
-prefer-compile-strategy = []
-prefer-system-strategy = []
-prefer-dynamic-libs = []
 minimal-build = []
 experimental = []
 mimalloc = []

README.md

@@ -11,10 +11,7 @@ See [the docs](https://docs.rs/ort) and [`examples/`](https://github.com/pykeio/
 - `fetch-models`: Enables fetching models from the ONNX Model Zoo; not recommended for production.
 - `generate-bindings`: Update/generate ONNX Runtime bindings with `bindgen`. Requires [libclang](https://clang.llvm.org/doxygen/group__CINDEX.html).
 - `copy-dylibs`: Copy dynamic libraries to the Cargo `target` folder.
-- `prefer-system-strategy`: Uses the `system` compile [strategy](#strategies) by default; requires users to provide ONNX Runtime libraries.
-    - `prefer-dynamic-libs`: By default, if the path pointed to by `ORT_LIB_LOCATION` contains static libraries, `ort` will link to them rather than dynamic libraries. This feature prefers linking to dynamic libraries instead.
-- `prefer-compile-strategy`: Uses the `compile` [strategy](#strategies) by default; will take a *very* long time, but allows for easy static linking, avoiding [the DLL hell](#shared-library-hell).
-    - *These features only apply when using the compile strategy:*
+- **Compile strategy features** - *These features only apply when using the compile strategy.*
     - `compile-static`: Compiles ONNX Runtime as a static library.
     - `mimalloc`: Uses the (usually) faster mimalloc memory allocation library instead of the platform default.
     - `experimental`: Compiles Microsoft experimental operators.

build.rs

@@ -1,4 +1,4 @@
-#![allow(dead_code)]
+#![allow(unused)]
 
 use std::{
 	borrow::Cow,
@@ -312,10 +312,7 @@ fn prepare_libort_dir() -> (PathBuf, bool) {
 
 	println!("cargo:rerun-if-env-changed={}", ORT_ENV_STRATEGY);
 
-	match strategy
-		.as_ref()
-		.map_or_else(|_| if cfg!(feature = "prefer-compile-strategy") { "compile" } else { "download" }, String::as_str)
-	{
+	match strategy.as_ref().map_or("download", String::as_str) {
 		"download" => {
 			if target.contains("macos") {
 				incompatible_providers![cuda, onednn, openvino, openmp, vitis_ai, tvm, tensorrt, migraphx, directml, winml, acl, armnn, rocm];
@@ -498,12 +495,6 @@ fn prepare_libort_dir() -> (PathBuf, bool) {
 	}
 }
 
-#[cfg(not(feature = "generate-bindings"))]
-fn generate_bindings(_include_dir: &Path) {
-	println!("[ort] bindings not generated automatically; using committed bindings instead.");
-	println!("[ort] enable the `generate-bindings` feature to generate fresh bindings.");
-}
-
 #[cfg(feature = "generate-bindings")]
 fn generate_bindings(include_dir: &Path) {
 	let clang_args = &[
@@ -538,23 +529,22 @@ fn generate_bindings(include_dir: &Path) {
 	bindings.write_to_file(&generated_file).expect("Couldn't write bindings!");
 }
 
-#[cfg(feature = "disable-build-script")]
-fn main() {}
-
-#[cfg(not(feature = "disable-build-script"))]
 fn main() {
-	let (install_dir, needs_link) = prepare_libort_dir();
+	if !std::env::var("DOCS_RS").is_ok() {
+		let (install_dir, needs_link) = prepare_libort_dir();
 
-	let include_dir = install_dir.join("include");
-	let lib_dir = install_dir.join("lib");
+		let include_dir = install_dir.join("include");
+		let lib_dir = install_dir.join("lib");
 
-	if needs_link {
-		println!("cargo:rustc-link-lib=onnxruntime");
-		println!("cargo:rustc-link-search=native={}", lib_dir.display());
+		if needs_link {
+			println!("cargo:rustc-link-lib=onnxruntime");
+			println!("cargo:rustc-link-search=native={}", lib_dir.display());
+		}
+
+		println!("cargo:rerun-if-env-changed={}", ORT_ENV_STRATEGY);
+		println!("cargo:rerun-if-env-changed={}", ORT_ENV_SYSTEM_LIB_LOCATION);
+
+		#[cfg(feature = "generate-bindings")]
+		generate_bindings(&include_dir);
 	}
-
-	println!("cargo:rerun-if-env-changed={}", ORT_ENV_STRATEGY);
-	println!("cargo:rerun-if-env-changed={}", ORT_ENV_SYSTEM_LIB_LOCATION);
-
-	generate_bindings(&include_dir);
 }