WIP test for new build system design

Author: emmatyping

Cargo.lock

@@ -1,6 +1,6 @@
 [workspace]
 resolver = "3"
 members = [
-    "Modules/_base64",
+    "Modules/_base64", "Modules/cpython-build-helper", "Modules/cpython-rust-staticlib",
     "Modules/cpython-sys"
 ]

Cargo.toml

@@ -178,7 +178,8 @@ CONFINCLUDEPY=	$(CONFINCLUDEDIR)/python$(LDVERSION)
 SHLIB_SUFFIX=	@SHLIB_SUFFIX@
 EXT_SUFFIX=	@EXT_SUFFIX@
 LDSHARED=	@LDSHARED@ $(PY_LDFLAGS)
-BLDSHARED=	@BLDSHARED@ $(PY_CORE_LDFLAGS)
+BLDSHARED_EXE= @BLDSHARED_EXE@
+BLDSHARED_ARGS=	@BLDSHARED_ARGS@ $(PY_CORE_LDFLAGS)
 LDCXXSHARED=	@LDCXXSHARED@ $(PY_LDFLAGS)
 DESTSHARED=	$(BINLIBDEST)/lib-dynload
 

Makefile.pre.in

@@ -6,6 +6,10 @@ edition = "2024"
 [dependencies]
 cpython-sys ={ path = "../cpython-sys" }
 
+[build-dependencies]
+cpython-build-helper = { path = "../cpython-build-helper" }
+
 [lib]
 name = "_base64"
-crate-type = ["staticlib"]
+# For shared builds, we generate a c dynamic library. Static builds use the rlib
+crate-type = ["cdylib", "rlib"]

Modules/_base64/Cargo.toml

@@ -0,0 +1,5 @@
+use cpython_build_helper::print_linker_args;
+
+fn main() {
+    print_linker_args();
+}

Modules/_base64/build.rs

@@ -0,0 +1,7 @@
+[package]
+name = "cpython-build-helper"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
+shlex = "1.3"

Modules/cpython-build-helper/Cargo.toml

@@ -0,0 +1,4 @@
+# cpython-build-helper
+
+This crate is used in Rust modules `build.rs` files to help do common tasks such
+as passing necessary link arguments.

Modules/cpython-build-helper/README.md

@@ -0,0 +1,17 @@
+use std::env;
+
+/// Print necessary link arguments for the library depending on the build
+/// configuration (static or shared)
+pub fn print_linker_args() {
+    let shared_build = env::var("RUST_SHARED_BUILD").expect("RUST_SHARED_BUILD not set in Makefile?");
+    if shared_build == "1" {
+        let build_shared_args =
+            env::var("BLDSHARED_ARGS").expect("BLDSHARED_ARGS not set in Makefile?");
+        // TODO(emmatyping): Ideally, we would not need to split the args here and take shlex
+        // as a dependency.
+        for arg in shlex::split(&build_shared_args).expect("Invalid BUILDSHARED_ARGS") {
+            println!("cargo:rustc-link-arg={}", arg);
+        }
+    }
+    // Static linker configuration is in cpython-rust-staticlib
+}

Modules/cpython-build-helper/src/lib.rs

@@ -0,0 +1,11 @@
+[package]
+name = "cpython-rust-staticlib"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
+_base64 ={ path = "../_base64" }
+
+[lib]
+name = "cpython_rust_staticlib"
+crate-type = ["staticlib"]

Modules/cpython-rust-staticlib/Cargo.toml

@@ -0,0 +1 @@
+pub use _base64::PyInit__base64;