Ignore unrelated attributes in the default-hidden-visibility test.

Before this commit the difference between `internal constant` vs
`constant` could lead to a test failure, even though both of these
combinations have no `hidden` attribute (and presence of the `hidden`
attribute is ultimately the only aspect that the test should care
about).

Author: anforowicz

tests/codegen/default-hidden-visibility.rs

@@ -18,6 +18,16 @@
 //
 //     ignore-wasm32
 
+// We verify that using the command line marks the `exported_symbol` as `hidden`
+// and that it is not `hidden` otherwise.  We don't verify other attributes of
+// the symbol, because they vary depending on the target (e.g. in the `DEFAULT`
+// behavior on `i686-unknown-linux-musl` the symbol is `internal constant` while
+// on `x86_64-unknown-linux-gnu` it is just `constant`).
+//
+// DEFAULT-NOT: @{{.*}}default_hidden_visibility{{.*}}exported_symbol{{.*}} ={{.*}} hidden
+// NO-NOT:      @{{.*}}default_hidden_visibility{{.*}}exported_symbol{{.*}} ={{.*}} hidden
+// YES:         @{{.*}}default_hidden_visibility{{.*}}exported_symbol{{.*}} ={{.*}} hidden
+
 // The test scenario is specifically about visibility of symbols exported out of dynamically linked
 // libraries.
 #![crate_type = "dylib"]
@@ -26,11 +36,5 @@
 // (e.g. the test doesn't use `#[no_mangle]`, because currently it implies that
 // the symbol should be exported;  we don't want that - we want to test the *default*
 // export setting instead).
-// .
-// We want to verify that the cmdline flag affects the visibility of this symbol:
-//
-// DEFAULT: @{{.*}}default_hidden_visibility{{.*}}exported_symbol{{.*}} = constant
-// YES:     @{{.*}}default_hidden_visibility{{.*}}exported_symbol{{.*}} = hidden constant
-// NO:      @{{.*}}default_hidden_visibility{{.*}}exported_symbol{{.*}} = constant
 #[used]
 pub static exported_symbol: [u8; 6] = *b"foobar";