rewrite stable-symbol-names to rmake

Author: Oneirical

src/tools/tidy/src/allowed_run_make_makefiles.txt

@@ -168,7 +168,6 @@ run-make/share-generics-dylib/Makefile
 run-make/silly-file-names/Makefile
 run-make/simd-ffi/Makefile
 run-make/split-debuginfo/Makefile
-run-make/stable-symbol-names/Makefile
 run-make/static-dylib-by-default/Makefile
 run-make/static-extern-type/Makefile
 run-make/staticlib-blank-lib/Makefile

tests/run-make/stable-symbol-names/Makefile

@@ -0,0 +1,63 @@
+// A typo in rustc caused generic symbol names to be non-deterministic -
+// that is, it was possible to compile the same file twice with no changes
+// and get outputs with different symbol names.
+// This test compiles each of the two crates twice, and checks that each output
+// contains exactly the same symbol names.
+// Additionally, both crates should agree on the same symbol names for monomorphic
+// functions.
+// See https://github.com/rust-lang/rust/issues/32554
+
+use run_make_support::{fs_wrapper, llvm_readobj, regex, rust_lib_name, rustc};
+use std::collections::HashSet;
+
+fn main() {
+    // test 1: first file
+    rustc().input("stable-symbol-names1.rs").run();
+    let sym1 = process_symbols("stable_symbol_names1", "generic_|mono_");
+    fs_wrapper::remove_file(rust_lib_name("stable_symbol_names1"));
+    rustc().input("stable-symbol-names1.rs").run();
+    let sym2 = process_symbols("stable_symbol_names1", "generic_|mono_");
+    assert_eq!(sym1, sym2);
+
+    // test 2: second file
+    rustc().input("stable-symbol-names2.rs").run();
+    let sym1 = process_symbols("stable_symbol_names2", "generic_|mono_");
+    fs_wrapper::remove_file(rust_lib_name("stable_symbol_names2"));
+    rustc().input("stable-symbol-names2.rs").run();
+    let sym2 = process_symbols("stable_symbol_names2", "generic_|mono_");
+    assert_eq!(sym1, sym2);
+
+    // test 3: crossed files
+    let sym1 = process_symbols("stable_symbol_names1", "mono_");
+    let sym2 = process_symbols("stable_symbol_names2", "mono_");
+    assert_eq!(sym1, sym2);
+}
+
+#[track_caller]
+fn process_symbols(path: &str, symbol: &str) -> Vec<String> {
+    // Dump all symbols.
+    let out = llvm_readobj().input(rust_lib_name(path)).arg("--symbols").run().stdout_utf8();
+    // Extract only lines containing `symbol`.
+    let out = out.lines().filter(|&x| x.contains(symbol));
+    // From those lines, extract just the symbol name via `regex`, which:
+    //   * always starts with "_ZN" and ends with "E" (`legacy` mangling)
+    //   * always starts with "_R" (`v0` mangling)
+    let legacy_pattern = regex::Regex::new(r"_ZN.*E").unwrap();
+    let v0_pattern = regex::Regex::new(r"_R[a-zA-Z0-9_]*").unwrap();
+
+    // HashSet - duplicates should be excluded!
+    let mut symbols: HashSet<String> = HashSet::new();
+    for line in out {
+        if let Some(mat) = legacy_pattern.find(line) {
+            symbols.insert(mat.as_str().to_string());
+        }
+        if let Some(mat) = v0_pattern.find(line) {
+            symbols.insert(mat.as_str().to_string());
+        }
+    }
+
+    let mut symbols: Vec<String> = symbols.into_iter().collect();
+    // Sort those symbol names for deterministic comparison.
+    symbols.sort();
+    symbols
+}