Auto merge of #142843 - dpaoliello:reproducible-build-2, r=<try>

Enable reproducible-build-2 for Windows

Works with MSVC if instructing the linker to avoid timestamps and deleting the PDB between compilations.

Addresses item in #128602

---

try-job: x86_64-mingw-*
try-job: x86_64-msvc-*
try-job: i686-msvc-*

Author: rust-bors[bot]

src/tools/run-make-support/src/lib.rs

@@ -83,7 +83,7 @@ pub use run::{cmd, run, run_fail, run_with_args};
 
 /// Helpers for checking target information.
 pub use targets::{
-    apple_os, is_aix, is_darwin, is_msvc, is_windows, is_windows_gnu, is_win7, llvm_components_contain,
+    apple_os, is_aix, is_darwin, is_msvc, is_windows, is_windows_gnu, is_windows_msvc, is_win7, llvm_components_contain,
     target, uname,
 };
 

src/tools/run-make-support/src/targets.rs

@@ -28,6 +28,12 @@ pub fn is_windows_gnu() -> bool {
     target().ends_with("windows-gnu")
 }
 
+/// Check if target is windows-gnu.
+#[must_use]
+pub fn is_windows_msvc() -> bool {
+    target().ends_with("windows-msvc")
+}
+
 /// Check if target is win7.
 #[must_use]
 pub fn is_win7() -> bool {

tests/run-make/reproducible-build-2/rmake.rs

@@ -7,21 +7,32 @@
 // See https://github.com/rust-lang/rust/issues/34902
 
 //@ ignore-cross-compile
-//@ ignore-windows
-// Reasons:
-// 1. The object files are reproducible, but their paths are not, which causes
-// the first assertion in the test to fail.
-// 2. When the sysroot gets copied, some symlinks must be re-created,
-// which is a privileged action on Windows.
 
-use run_make_support::{rfs, rust_lib_name, rustc};
+use run_make_support::{is_windows_msvc, rfs, rust_lib_name, rustc};
 
 fn main() {
     // test 1: fat lto
     rustc().input("reproducible-build-aux.rs").run();
-    rustc().input("reproducible-build.rs").arg("-Clto=fat").output("reproducible-build").run();
+    let make_reproducible_build = || {
+        let mut reproducible_build = rustc();
+        reproducible_build
+            .input("reproducible-build.rs")
+            .arg("-Clto=fat")
+            .output("reproducible-build");
+        if is_windows_msvc() {
+            // Avoids timestamps, etc. when linking.
+            reproducible_build.arg("-Clink-arg=/Brepro");
+        }
+        reproducible_build.run();
+    };
+    make_reproducible_build();
     rfs::rename("reproducible-build", "reproducible-build-a");
-    rustc().input("reproducible-build.rs").arg("-Clto=fat").output("reproducible-build").run();
+    if is_windows_msvc() {
+        // Linker acts differently if there is already a PDB file with the same
+        // name.
+        rfs::remove_file("reproducible-build.pdb");
+    }
+    make_reproducible_build();
     assert_eq!(rfs::read("reproducible-build"), rfs::read("reproducible-build-a"));
 
     // test 2: sysroot