moved building to lib with Once

crates/valgrind/Cargo.toml

@@ -2,22 +2,10 @@
 name = "valgrind"
 version = "0.1.0"
 edition = "2021"
+authors = ["The Roc Contributors"]
+license = "UPL-1.0"
 
-# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
-[dependencies]
-roc_cli = { path = "../cli" }
-cli_utils = { path = "../cli_utils" }
-roc_build = { path = "../compiler/build" }
-roc_mono = { path = "../compiler/mono" }
-roc_load = { path = "../compiler/load" }
-roc_reporting = { path = "../reporting" }
-roc_packaging = { path = "../packaging" }
-bumpalo.workspace = true
-target-lexicon.workspace = true
-tempfile.workspace = true
-indoc.workspace = true
-
-[build-dependencies]
+[dev-dependencies]
 roc_cli = { path = "../cli" }
 cli_utils = { path = "../cli_utils" }
 roc_build = { path = "../compiler/build" }

crates/valgrind/build.rs

@@ -1,28 +0,0 @@
-#[cfg(all(target_os = "linux"))]
-fn main() {
-    use roc_build::link::preprocessed_host_filename;
-    use roc_linker::build_and_preprocess_host;
-
-    let platform_main_roc = std::env::current_dir()
-        .unwrap()
-        .join("zig-platform/main.roc");
-
-    // tests always run on the host
-    let target = target_lexicon::Triple::host();
-
-    // the preprocessed host is stored beside the platform's main.roc
-    let preprocessed_host_path =
-        platform_main_roc.with_file_name(preprocessed_host_filename(&target).unwrap());
-
-    build_and_preprocess_host(
-        roc_mono::ir::OptLevel::Normal,
-        &target,
-        &platform_main_roc,
-        &preprocessed_host_path,
-        vec![String::from("mainForHost")],
-        vec![],
-    );
-}
-
-#[cfg(not(all(target_os = "linux")))]
-fn main() {}

crates/valgrind/src/lib.rs

@@ -1,6 +1,35 @@
 #![cfg(test)]
 
 use indoc::indoc;
+use std::sync::Once;
+
+static BUILD_ONCE: Once = Once::new();
+
+#[cfg(all(target_os = "linux"))]
+fn build_host() {
+    use roc_build::link::preprocessed_host_filename;
+    use roc_linker::build_and_preprocess_host;
+
+    let platform_main_roc = std::env::current_dir()
+        .unwrap()
+        .join("zig-platform/main.roc");
+
+    // tests always run on the host
+    let target = target_lexicon::Triple::host();
+
+    // the preprocessed host is stored beside the platform's main.roc
+    let preprocessed_host_path =
+        platform_main_roc.with_file_name(preprocessed_host_filename(&target).unwrap());
+
+    build_and_preprocess_host(
+        roc_mono::ir::OptLevel::Normal,
+        &target,
+        &platform_main_roc,
+        &preprocessed_host_path,
+        vec![String::from("mainForHost")],
+        vec![],
+    );
+}
 
 fn valgrind_test(source: &str) {
     #[cfg(target_os = "linux")]
@@ -18,6 +47,9 @@ fn valgrind_test(source: &str) {
 fn valgrind_test_linux(source: &str) {
     use roc_cli::build::BuiltFile;
 
+    // the host is identical for all tests so we only want to build it once
+    BUILD_ONCE.call_once(build_host);
+
     let pf = std::env::current_dir()
         .unwrap()
         .join("zig-platform/main.roc");

crates/valgrind/zig-platform/.gitignore

@@ -0,0 +1,2 @@
+dynhost
+libapp.so