Auto merge of #128787 - Oneirical:infohazardous-deprogram, r=<try>

Coalesce `dep-info`, `dep-info-spaces` and `dep-info-doesnt-run-much` `run-make` tests into `dep-info` rmake.rs

Part of #121876 and the associated [Google Summer of Code project](https://blog.rust-lang.org/2024/05/01/gsoc-2024-selected-projects.html).

This is one of the most ancient tests in the `run-make` directory and its Makefile does some unexpected things, like creating and deleting a `done` directory over and over, sleeping at certain times (this is the [commit](0d9fd8e) that added the `sleep`).

I tried to preserve the intent of the test, which is smoke-testing that `dep-info` works.

try-job: x86_64-msvc
try-job: i686-mingw
try-job: aarch64-gnu
try-job: aarch64-apple
try-job: test-various
try-job: armhf-gnu
try-job: dist-various-1

Author: bors

src/tools/tidy/src/allowed_run_make_makefiles.txt

@@ -1,8 +1,5 @@
 run-make/branch-protection-check-IBT/Makefile
 run-make/cat-and-grep-sanity-check/Makefile
-run-make/dep-info-doesnt-run-much/Makefile
-run-make/dep-info-spaces/Makefile
-run-make/dep-info/Makefile
 run-make/emit-to-stdout/Makefile
 run-make/extern-fn-reachable/Makefile
 run-make/incr-add-rust-src-component/Makefile

tests/run-make/dep-info-doesnt-run-much/Makefile

@@ -0,0 +1,36 @@
+// This is a simple smoke test for rustc's `--emit dep-info` feature. It prints out
+// information about dependencies in a Makefile-compatible format, as a `.d` file.
+
+// This test first checks that emitting dep-info disables static analysis, preventing
+// compilation of `erroneous.rs` from causing a compilation failure.
+// Then, it checks that compilation using the flag is successful in general, even with
+// empty source files or source files that contain a whitespace character.
+
+// Finally, it removes one dependency and checks that compilation is still successful.
+// See https://github.com/rust-lang/rust/pull/10698
+
+use run_make_support::{rfs, rustc};
+
+fn main() {
+    // We're only emitting dep info, so we shouldn't be running static analysis to
+    // figure out that this program is erroneous.
+    rustc().input("erroneous.rs").emit("dep-info").run();
+
+    rustc().input("lib.rs").emit("dep-info,link").crate_type("lib").run();
+    rfs::remove_file("foo.rs");
+    rfs::create_file("foo.rs");
+    // Compilation should succeed even if `foo.rs` is empty.
+    rustc().input("lib.rs").emit("dep-info,link").crate_type("lib").run();
+
+    // Again, with a space in the filename this time around.
+    rustc().input("lib_foofoo.rs").emit("dep-info,link").crate_type("lib").run();
+    rfs::remove_file("foo foo.rs");
+    rfs::create_file("foo foo.rs");
+    // Compilation should succeed even if `foo foo.rs` is empty.
+    rustc().input("lib_foofoo.rs").emit("dep-info,link").crate_type("lib").run();
+
+    // When a source file is deleted, compilation should still succeed if the library
+    // also loses this source file dependency.
+    rfs::remove_file("bar.rs");
+    rustc().input("lib2.rs").emit("dep-info,link").crate_type("lib").run();
+}