migrate fmt-write-bloat to rmake

Author: lolbinarycat

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

@@ -21,7 +21,7 @@ pub mod run;
 pub mod scoped_run;
 pub mod string;
 pub mod targets;
-
+pub mod symbols;
 // Internally we call our fs-related support module as `fs`, but re-export its content as `rfs`
 // to tests to avoid colliding with commonly used `use std::fs;`.
 mod fs;

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

@@ -0,0 +1,18 @@
+use std::path::Path;
+use std::fs;
+use object::{self, Object, SymbolIterator};
+
+/// iterate through the symbols in an object file.
+///
+/// uses a callback because SymbolIterator does not own its data
+pub fn with_symbol_iter<P, F, R>(path: P, func: F) -> R where
+    P: AsRef<Path>,
+    //I: Iterator + 'a,
+    F: FnOnce(&mut SymbolIterator<'_, '_>) -> R,
+{
+    let raw_bytes = fs::read(path).expect("unable to read file");
+    let f = object::File::parse(raw_bytes.as_slice())
+        .expect("unable to parse file");
+    let mut iter = f.symbols();
+    func(&mut iter)
+}

tests/run-make/fmt-write-bloat/Makefile

@@ -0,0 +1,23 @@
+//@ ignore-windows
+//@ ignore-cross-compile
+
+use run_make_support::{rustc, symbols::with_symbol_iter, object::ObjectSymbol};
+
+fn main() {
+    rustc().input("main.rs").run();
+    // panic machinery identifiers, these should not appear in the final binary
+    let mut panic_syms = vec!["panic_bounds_check", "Debug"];
+    if !cfg!(debug_assertions) {
+        // if debug assertions are allowed, we need to allow these,
+        // otherwise, add them to the list of symbols to deny.
+        panic_syms.extend_from_slice(&["panicking", "panic_fmt", "pad_integral", "Display"]);
+    }
+    with_symbol_iter("main", |syms| for sym in syms {
+        dbg!(&sym);
+        for panic_sym in &panic_syms {
+            if sym.name().unwrap().contains(panic_sym) {
+                panic!("{:?} contains {}", sym, panic_sym);
+            }
+        }
+    });
+}