rustc_codegen_utils: test demangler output, not just symbol names.

Cargo.lock

@@ -2688,6 +2688,7 @@ dependencies = [
  "flate2 1.0.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc 0.0.0",
+ "rustc-demangle 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc_data_structures 0.0.0",
  "rustc_metadata 0.0.0",
  "rustc_mir 0.0.0",

src/librustc_codegen_utils/Cargo.toml

@@ -13,6 +13,7 @@ test = false
 [dependencies]
 flate2 = "1.0"
 log = "0.4"
+rustc-demangle = "0.1.15"
 
 syntax = { path = "../libsyntax" }
 syntax_pos = { path = "../libsyntax_pos" }

src/librustc_codegen_utils/symbol_names_test.rs

@@ -39,8 +39,12 @@ impl<'a, 'tcx> SymbolNamesTest<'a, 'tcx> {
             if attr.check_name(SYMBOL_NAME) {
                 // for now, can only use on monomorphic names
                 let instance = Instance::mono(tcx, def_id);
-                let name = self.tcx.symbol_name(instance);
+                let mangled = self.tcx.symbol_name(instance);
-                tcx.sess.span_err(attr.span, &format!("symbol-name({})", name));
+                tcx.sess.span_err(attr.span, &format!("symbol-name({})", mangled));
+                if let Ok(demangling) = rustc_demangle::try_demangle(&mangled.as_str()) {
+                    tcx.sess.span_err(attr.span, &format!("demangling({})", demangling));
+                    tcx.sess.span_err(attr.span, &format!("demangling-alt({:#})", demangling));
+                }
             } else if attr.check_name(DEF_PATH) {
                 let path = tcx.def_path_str(def_id);
                 tcx.sess.span_err(attr.span, &format!("def-path({})", path));

src/test/ui/symbol-names/basic.rs

@@ -1,6 +1,9 @@
 #![feature(rustc_attrs)]
 
-#[rustc_symbol_name] //~ ERROR _ZN5basic4main
+#[rustc_symbol_name]
+//~^ ERROR symbol-name(_ZN5basic4main
+//~| ERROR demangling(basic::main
+//~| ERROR demangling-alt(basic::main)
 #[rustc_def_path] //~ ERROR def-path(main)
 fn main() {
 }

src/test/ui/symbol-names/basic.stderr

@@ -4,11 +4,23 @@ error: symbol-name(_ZN5basic4main17hd72940ef9669d526E)
 LL | #[rustc_symbol_name]
    | ^^^^^^^^^^^^^^^^^^^^
 
+error: demangling(basic::main::hd72940ef9669d526)
+  --> $DIR/basic.rs:3:1
+   |
+LL | #[rustc_symbol_name]
+   | ^^^^^^^^^^^^^^^^^^^^
+
+error: demangling-alt(basic::main)
+  --> $DIR/basic.rs:3:1
+   |
+LL | #[rustc_symbol_name]
+   | ^^^^^^^^^^^^^^^^^^^^
+
 error: def-path(main)
-  --> $DIR/basic.rs:4:1
+  --> $DIR/basic.rs:7:1
    |
 LL | #[rustc_def_path]
    | ^^^^^^^^^^^^^^^^^
 
-error: aborting due to 2 previous errors
+error: aborting due to 4 previous errors
 

src/test/ui/symbol-names/impl1.rs

@@ -5,7 +5,10 @@ mod foo {
     pub struct Foo { x: u32 }
 
     impl Foo {
-        #[rustc_symbol_name] //~ ERROR _ZN5impl13foo3Foo3bar
+        #[rustc_symbol_name]
+        //~^ ERROR symbol-name(_ZN5impl13foo3Foo3bar
+        //~| ERROR demangling(impl1::foo::Foo::bar
+        //~| ERROR demangling-alt(impl1::foo::Foo::bar)
         #[rustc_def_path] //~ ERROR def-path(foo::Foo::bar)
         fn bar() { }
     }
@@ -15,7 +18,10 @@ mod bar {
     use foo::Foo;
 
     impl Foo {
-        #[rustc_symbol_name] //~ ERROR _ZN5impl13bar33_$LT$impl$u20$impl1..foo..Foo$GT$3baz
+        #[rustc_symbol_name]
+        //~^ ERROR symbol-name(_ZN5impl13bar33_$LT$impl$u20$impl1..foo..Foo$GT$3baz
+        //~| ERROR demangling(impl1::bar::<impl impl1::foo::Foo>::baz
+        //~| ERROR demangling-alt(impl1::bar::<impl impl1::foo::Foo>::baz)
         #[rustc_def_path] //~ ERROR def-path(bar::<impl foo::Foo>::baz)
         fn baz() { }
     }

src/test/ui/symbol-names/impl1.stderr

@@ -4,23 +4,47 @@ error: symbol-name(_ZN5impl13foo3Foo3bar17he53b9bee7600ed8dE)
 LL |         #[rustc_symbol_name]
    |         ^^^^^^^^^^^^^^^^^^^^
 
+error: demangling(impl1::foo::Foo::bar::he53b9bee7600ed8d)
+  --> $DIR/impl1.rs:8:9
+   |
+LL |         #[rustc_symbol_name]
+   |         ^^^^^^^^^^^^^^^^^^^^
+
+error: demangling-alt(impl1::foo::Foo::bar)
+  --> $DIR/impl1.rs:8:9
+   |
+LL |         #[rustc_symbol_name]
+   |         ^^^^^^^^^^^^^^^^^^^^
+
 error: def-path(foo::Foo::bar)
-  --> $DIR/impl1.rs:9:9
+  --> $DIR/impl1.rs:12:9
    |
 LL |         #[rustc_def_path]
    |         ^^^^^^^^^^^^^^^^^
 
 error: symbol-name(_ZN5impl13bar33_$LT$impl$u20$impl1..foo..Foo$GT$3baz17h86c41f0462d901d4E)
-  --> $DIR/impl1.rs:18:9
+  --> $DIR/impl1.rs:21:9
+   |
+LL |         #[rustc_symbol_name]
+   |         ^^^^^^^^^^^^^^^^^^^^
+
+error: demangling(impl1::bar::<impl impl1::foo::Foo>::baz::h86c41f0462d901d4)
+  --> $DIR/impl1.rs:21:9
+   |
+LL |         #[rustc_symbol_name]
+   |         ^^^^^^^^^^^^^^^^^^^^
+
+error: demangling-alt(impl1::bar::<impl impl1::foo::Foo>::baz)
+  --> $DIR/impl1.rs:21:9
    |
 LL |         #[rustc_symbol_name]
    |         ^^^^^^^^^^^^^^^^^^^^
 
 error: def-path(bar::<impl foo::Foo>::baz)
-  --> $DIR/impl1.rs:19:9
+  --> $DIR/impl1.rs:25:9
    |
 LL |         #[rustc_def_path]
    |         ^^^^^^^^^^^^^^^^^
 
-error: aborting due to 4 previous errors
+error: aborting due to 8 previous errors
 

src/test/ui/symbol-names/issue-60925.rs

@@ -14,7 +14,9 @@ mod foo {
 
     impl Foo<::llvm::Foo> {
         #[rustc_symbol_name]
-//~^ ERROR _ZN11issue_609253foo36Foo$LT$issue_60925..llv$6d$..Foo$GT$3foo17h059a991a004536adE
+        //~^ ERROR symbol-name(_ZN11issue_609253foo36Foo$LT$issue_60925..llv$6d$..Foo$GT$3foo
+        //~| ERROR demangling(issue_60925::foo::Foo<issue_60925::llv$6d$..Foo$GT$::foo
+        //~| ERROR demangling-alt(issue_60925::foo::Foo<issue_60925::llv$6d$..Foo$GT$::foo)
         pub(crate) fn foo() {
             for _ in 0..0 {
                 for _ in &[::dummy()] {

src/test/ui/symbol-names/issue-60925.stderr

@@ -4,5 +4,17 @@ error: symbol-name(_ZN11issue_609253foo36Foo$LT$issue_60925..llv$6d$..Foo$GT$3fo
 LL |         #[rustc_symbol_name]
    |         ^^^^^^^^^^^^^^^^^^^^
 
-error: aborting due to previous error
+error: demangling(issue_60925::foo::Foo<issue_60925::llv$6d$..Foo$GT$::foo::h059a991a004536ad)
+  --> $DIR/issue-60925.rs:16:9
+   |
+LL |         #[rustc_symbol_name]
+   |         ^^^^^^^^^^^^^^^^^^^^
+
+error: demangling-alt(issue_60925::foo::Foo<issue_60925::llv$6d$..Foo$GT$::foo)
+  --> $DIR/issue-60925.rs:16:9
+   |
+LL |         #[rustc_symbol_name]
+   |         ^^^^^^^^^^^^^^^^^^^^
+
+error: aborting due to 3 previous errors