rewrite output-with-hyphens to rmake format

src/tools/tidy/src/allowed_run_make_makefiles.txt

@@ -157,7 +157,6 @@ run-make/optimization-remarks-dir/Makefile
 run-make/output-filename-conflicts-with-directory/Makefile
 run-make/output-filename-overwrites-input/Makefile
 run-make/output-type-permutations/Makefile
-run-make/output-with-hyphens/Makefile
 run-make/override-aliased-flags/Makefile
 run-make/overwrite-input/Makefile
 run-make/panic-abort-eh_frame/Makefile

tests/run-make/output-with-hyphens/rmake.rs

@@ -0,0 +1,18 @@
+// Rust files with hyphens in their filename should
+// not result in compiled libraries keeping that hyphen -
+// it should become an underscore. Only bin executables
+// should keep the hyphen. This test ensures that this rule
+// remains enforced.
+// See https://github.com/rust-lang/rust/pull/23786
+
+//@ ignore-cross-compile
+
+use run_make_support::rustc;
+use std::path::Path;
+
+fn main() {
+    rustc().input("foo-bar.rs").crate_type("bin").run();
+    Path::new(bin_name("foo-bar")).exists();
+    rustc().input("foo-bar.rs").crate_type("lib").run();
+    Path::new(bin_name("libfoo_bar.rlib")).exists();
+}