[testsuite] Scan for warning diagnostics, too

..., and update testcases as appropriate.

In addition to (very) few 'unreachable expression', 'unreachable statement', or
'function is never used', most of these are to catch expected 'unused name'
warning diagnostics.  Of the latter, a few are XFAILed for
<https://github.com/Rust-GCC/gccrs/issues/361> "Names prefixed with underscore
shouldn't get 'unused name' diagnostic".

89 files changed, 149 insertions, 8 deletions

diff --git a/gcc/testsuite/lib/rust.exp b/gcc/testsuite/lib/rust.exp
index 3f2bb55..7d2896b 100644
--- a/gcc/testsuite/lib/rust.exp
+++ b/gcc/testsuite/lib/rust.exp
@@ -178,11 +178,10 @@ proc rust_target_compile { source dest type options } {
     set options [concat "$ALWAYS_RUSTFLAGS" $options]
     set options [dg-additional-files-options $options $source]
 
-    ## FIXME: until the compiler is made less verbose, we need to prune its output completely.
-    # Only keep line containing error so that the test will correctly report the error and the test
-    # can FAIL or XFAIL
+    ## FIXME: until the compiler is made less verbose, we need to prune its output almost completely.
+    # Only keep lines containing certain diagnostics so that we can check these.
     global additional_prunes
-    lappend additional_prunes "^((?!error: ).)*$"
+    lappend additional_prunes "^((?!(error: |warning: )).)*$"
 
     return [target_compile $source $dest $type $options]
 }
diff --git a/gcc/testsuite/rust.test/compile/arithmetic_expressions1.rs b/gcc/testsuite/rust.test/compile/arithmetic_expressions1.rs
index efc63f5..4c3ee77 100644
--- a/gcc/testsuite/rust.test/compile/arithmetic_expressions1.rs
+++ b/gcc/testsuite/rust.test/compile/arithmetic_expressions1.rs
@@ -1,3 +1,5 @@
+// { dg-prune-output "warning: unused name" } as there are many of these expected.
+
 fn main() {
     let a: i32 = 1;
     let b: f32 = 5f32;
diff --git a/gcc/testsuite/rust.test/compile/array_type_infer.rs b/gcc/testsuite/rust.test/compile/array_type_infer.rs
index f6a6182..6f21bf2 100644
--- a/gcc/testsuite/rust.test/compile/array_type_infer.rs
+++ b/gcc/testsuite/rust.test/compile/array_type_infer.rs
@@ -1,3 +1,4 @@
 fn main() {
     let arr: [_; 5] = [1, 2, 3, 4, 5];
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/array_zero_length.rs b/gcc/testsuite/rust.test/compile/array_zero_length.rs
index a3acc15..3155b1c 100644
--- a/gcc/testsuite/rust.test/compile/array_zero_length.rs
+++ b/gcc/testsuite/rust.test/compile/array_zero_length.rs
@@ -1,3 +1,4 @@
 fn main() {
     let arr = ["Hello"; 0];
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/arrays1.rs b/gcc/testsuite/rust.test/compile/arrays1.rs
index f7e66af..7250e0f 100644
--- a/gcc/testsuite/rust.test/compile/arrays1.rs
+++ b/gcc/testsuite/rust.test/compile/arrays1.rs
@@ -3,5 +3,7 @@ fn main() {
     let xy = [6, 7, 8];
 
     let a = xs[0];
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let b = xy[2];
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/arrays2.rs b/gcc/testsuite/rust.test/compile/arrays2.rs
index a3c8523..55491f3 100644
--- a/gcc/testsuite/rust.test/compile/arrays2.rs
+++ b/gcc/testsuite/rust.test/compile/arrays2.rs
@@ -2,6 +2,7 @@ fn main() {
     let mut array: [i32; 3] = [0; 3];
 
     let a = array[0];
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let mut c;
     c = array[2];
 }
diff --git a/gcc/testsuite/rust.test/compile/arrays_index1.rs b/gcc/testsuite/rust.test/compile/arrays_index1.rs
index 8dd1c04..1fe5de9 100644
--- a/gcc/testsuite/rust.test/compile/arrays_index1.rs
+++ b/gcc/testsuite/rust.test/compile/arrays_index1.rs
@@ -2,6 +2,7 @@ fn main() {
     let mut array: [i32; 3] = [0; 3];
 
     let a = array[0];
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let x = 0;
     let mut c;
     c = array[x+1];
diff --git a/gcc/testsuite/rust.test/compile/block_expr1.rs b/gcc/testsuite/rust.test/compile/block_expr1.rs
index fe63252..011cc1f 100644
--- a/gcc/testsuite/rust.test/compile/block_expr1.rs
+++ b/gcc/testsuite/rust.test/compile/block_expr1.rs
@@ -20,7 +20,9 @@ fn test5(x: i32) -> i32 {
 
 fn main() {
     let call3: i32 = { test3(3) + 2 };
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let call5 = {
+        // { dg-warning "unused name" "" { target *-*-* } .-1 }
         let a = test5(5);
         a + 1
     };
diff --git a/gcc/testsuite/rust.test/compile/block_expr2.rs b/gcc/testsuite/rust.test/compile/block_expr2.rs
index a66ca7b..7c3ff69 100644
--- a/gcc/testsuite/rust.test/compile/block_expr2.rs
+++ b/gcc/testsuite/rust.test/compile/block_expr2.rs
@@ -5,6 +5,7 @@ fn test() -> i32 {
 fn main() {
     let a = { test() };
     let b = {
+        // { dg-warning "unused name" "" { target *-*-* } .-1 }
         if a > 10 {
             a - 1
         } else {
diff --git a/gcc/testsuite/rust.test/compile/block_expr3.rs b/gcc/testsuite/rust.test/compile/block_expr3.rs
index a8b2f27..6914b63 100644
--- a/gcc/testsuite/rust.test/compile/block_expr3.rs
+++ b/gcc/testsuite/rust.test/compile/block_expr3.rs
@@ -2,6 +2,7 @@ fn main() {
     let x = 111;
 
     let a = {
+        // { dg-warning "unused name" "" { target *-*-* } .-1 }
         if x == 10 {
             123
         } else if x < 10 {
diff --git a/gcc/testsuite/rust.test/compile/block_expr4.rs b/gcc/testsuite/rust.test/compile/block_expr4.rs
index 35a5cd0..da033ef 100644
--- a/gcc/testsuite/rust.test/compile/block_expr4.rs
+++ b/gcc/testsuite/rust.test/compile/block_expr4.rs
@@ -4,4 +4,5 @@ fn foo() -> isize {
 
 fn main() {
     let a = foo();
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/block_expr_parser_bug.rs b/gcc/testsuite/rust.test/compile/block_expr_parser_bug.rs
index e583008..468aace 100644
--- a/gcc/testsuite/rust.test/compile/block_expr_parser_bug.rs
+++ b/gcc/testsuite/rust.test/compile/block_expr_parser_bug.rs
@@ -1,4 +1,5 @@
 fn main() {
     let a = 123;
     let b = if a > 10 { a - 1 } else { a + 1 };
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/cfg_attr.rs b/gcc/testsuite/rust.test/compile/cfg_attr.rs
index 95e636b..1915f34 100644
--- a/gcc/testsuite/rust.test/compile/cfg_attr.rs
+++ b/gcc/testsuite/rust.test/compile/cfg_attr.rs
@@ -2,6 +2,7 @@ use std::env; // Add one line so gccrs doesn't believe we're parsing a shebang
 
 #[cfg_attr(feature = "somefeature", attribute = "someattr")]
 struct Feature;
+// { dg-warning "unused name" "" { target *-*-* } .-1 }
 
 fn main() {
 }
diff --git a/gcc/testsuite/rust.test/compile/comparison_expr1.rs b/gcc/testsuite/rust.test/compile/comparison_expr1.rs
index d3c5263..ed71ec8 100644
--- a/gcc/testsuite/rust.test/compile/comparison_expr1.rs
+++ b/gcc/testsuite/rust.test/compile/comparison_expr1.rs
@@ -28,7 +28,11 @@ fn main() {
     let c: bool = is_positive(3);
     let d: bool = is_negative(4);
     let e: bool = is_positive_or_zero(5);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let f: bool = is_negative_or_zero(6);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let g: bool = a || b;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let h: bool = c && d;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/compile.exp b/gcc/testsuite/rust.test/compile/compile.exp
index 37cfd41..7c92d7a 100644
--- a/gcc/testsuite/rust.test/compile/compile.exp
+++ b/gcc/testsuite/rust.test/compile/compile.exp
@@ -28,7 +28,7 @@ dg-init
 set saved-dg-do-what-default ${dg-do-what-default}
 
 set dg-do-what-default "compile"
-gcc-dg-runtest [lsort [glob -nocomplain $srcdir/$subdir/*.rs]] "" "-w"
+gcc-dg-runtest [lsort [glob -nocomplain $srcdir/$subdir/*.rs]] "" ""
 set dg-do-what-default ${saved-dg-do-what-default}
 
 # All done.
diff --git a/gcc/testsuite/rust.test/compile/constant1.rs b/gcc/testsuite/rust.test/compile/constant1.rs
index e8ef96b..57bcb0b 100644
--- a/gcc/testsuite/rust.test/compile/constant1.rs
+++ b/gcc/testsuite/rust.test/compile/constant1.rs
@@ -5,4 +5,5 @@ fn main() {
     x = x + 1;
 
     let mut y = x + TEST_CONST;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/deadcode1.rs b/gcc/testsuite/rust.test/compile/deadcode1.rs
index ec6e240..1ba646f 100644
--- a/gcc/testsuite/rust.test/compile/deadcode1.rs
+++ b/gcc/testsuite/rust.test/compile/deadcode1.rs
@@ -1,5 +1,6 @@
 fn test1() -> i32 {
     return 2;
+    // { dg-warning "unreachable expression" "" { target *-*-* } .+1 }
     1
 }
 
@@ -9,10 +10,13 @@ fn test2(x: i32) -> i32 {
     } else {
         return 0;
     }
+    // { dg-warning "unreachable statement" "" { target *-*-* } .+1 }
     return 1;
 }
 
 fn main() {
     let call1 = test1();
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let call2 = test2(2);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/deref1.rs b/gcc/testsuite/rust.test/compile/deref1.rs
index 9bf3eb5..d715ce9 100644
--- a/gcc/testsuite/rust.test/compile/deref1.rs
+++ b/gcc/testsuite/rust.test/compile/deref1.rs
@@ -2,4 +2,5 @@ fn main() {
     let a = 123;
     let b = &a;
     let c = *b;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/float1.rs b/gcc/testsuite/rust.test/compile/float1.rs
index 57a746f..fbe8938 100644
--- a/gcc/testsuite/rust.test/compile/float1.rs
+++ b/gcc/testsuite/rust.test/compile/float1.rs
@@ -5,4 +5,5 @@ fn test(x: f32) -> f32 {
 fn main() {
     let a_float = 5.123;
     let call_test = test(a_float + 1.0);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/float_types.rs b/gcc/testsuite/rust.test/compile/float_types.rs
index 50b392e..7d3d298 100644
--- a/gcc/testsuite/rust.test/compile/float_types.rs
+++ b/gcc/testsuite/rust.test/compile/float_types.rs
@@ -1,3 +1,5 @@
+// { dg-prune-output "warning: unused name" } as there are many of these expected.
+
 fn main() {
     let a1: f32 = 1.0f32;
     let a2: f64 = 2.0f64;
diff --git a/gcc/testsuite/rust.test/compile/forward_decl_1.rs b/gcc/testsuite/rust.test/compile/forward_decl_1.rs
index a69c07e..b8403f9 100644
--- a/gcc/testsuite/rust.test/compile/forward_decl_1.rs
+++ b/gcc/testsuite/rust.test/compile/forward_decl_1.rs
@@ -3,6 +3,7 @@ fn main() {
     an_integer = test(1) + 3;
 
     let call_test = test(1);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
 
 fn test(x: i32) -> i32 {
diff --git a/gcc/testsuite/rust.test/compile/forward_decl_2.rs b/gcc/testsuite/rust.test/compile/forward_decl_2.rs
index ba9c963..efc3b0d 100644
--- a/gcc/testsuite/rust.test/compile/forward_decl_2.rs
+++ b/gcc/testsuite/rust.test/compile/forward_decl_2.rs
@@ -1,5 +1,6 @@
 fn main() {
     let y = x + 1;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
 
 static x: i32 = 3;
diff --git a/gcc/testsuite/rust.test/compile/forward_decl_3.rs b/gcc/testsuite/rust.test/compile/forward_decl_3.rs
index 257b0f7..0028ca5 100644
--- a/gcc/testsuite/rust.test/compile/forward_decl_3.rs
+++ b/gcc/testsuite/rust.test/compile/forward_decl_3.rs
@@ -1,5 +1,6 @@
 fn main() {
     let struct_test = Foo { one: 1, two: 2 };
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
 
 struct Foo {
diff --git a/gcc/testsuite/rust.test/compile/forward_decl_4.rs b/gcc/testsuite/rust.test/compile/forward_decl_4.rs
index dd8a725..e1fe51f 100644
--- a/gcc/testsuite/rust.test/compile/forward_decl_4.rs
+++ b/gcc/testsuite/rust.test/compile/forward_decl_4.rs
@@ -3,6 +3,7 @@ fn main() {
     x = x + 1;
 
     let mut y = x + TEST_CONST;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
 
 const TEST_CONST: i32 = 10;
diff --git a/gcc/testsuite/rust.test/compile/function_reference1.rs b/gcc/testsuite/rust.test/compile/function_reference1.rs
index 604bad0..dfbd01b 100644
--- a/gcc/testsuite/rust.test/compile/function_reference1.rs
+++ b/gcc/testsuite/rust.test/compile/function_reference1.rs
@@ -5,4 +5,5 @@ fn test(a: i32) -> i32 {
 fn main() {
     let a = test;
     let b = a(1);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/function_reference2.rs b/gcc/testsuite/rust.test/compile/function_reference2.rs
index 0b963b2..3c3e7c1 100644
--- a/gcc/testsuite/rust.test/compile/function_reference2.rs
+++ b/gcc/testsuite/rust.test/compile/function_reference2.rs
@@ -5,4 +5,5 @@ fn test(a: i32) -> i32 {
 fn main() {
     let a: fn(i32) -> i32 = test;
     let b = a(1);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/function_reference3.rs b/gcc/testsuite/rust.test/compile/function_reference3.rs
index 32f4728..0cb3181 100644
--- a/gcc/testsuite/rust.test/compile/function_reference3.rs
+++ b/gcc/testsuite/rust.test/compile/function_reference3.rs
@@ -9,10 +9,12 @@ fn test(a: i32) -> i32 {
 
 fn main() {
     let a = test(1);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 
     let b: fn(i32) -> i32 = test;
     let c = b(1);
 
     let d = Foo { a: test, b: c };
     let e = (d.a)(d.b);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/function_reference4.rs b/gcc/testsuite/rust.test/compile/function_reference4.rs
index a27f0e4..977e4c9 100644
--- a/gcc/testsuite/rust.test/compile/function_reference4.rs
+++ b/gcc/testsuite/rust.test/compile/function_reference4.rs
@@ -5,4 +5,5 @@ fn test(a: i32) -> i32 {
 fn main() {
     let a: fn(_) -> _ = test;
     let b = a(1);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/generics1.rs b/gcc/testsuite/rust.test/compile/generics1.rs
index 8a2965a..87bcdc8 100644
--- a/gcc/testsuite/rust.test/compile/generics1.rs
+++ b/gcc/testsuite/rust.test/compile/generics1.rs
@@ -13,29 +13,39 @@ fn main() {
     a1 = Foo { a: 1.0, b: false };
 
     let b1: f32 = a1.a;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let c1: bool = a1.b;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 
     let a2: GenericStruct<i8>;
     a2 = GenericStruct::<i8> { a: 1, b: 456 };
 
     let b2: i8 = a2.a;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let c2: usize = a2.b;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 
     let a3;
     a3 = GenericStruct::<i32> { a: 123, b: 456 };
 
     let b3: i32 = a3.a;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let c3: usize = a3.b;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 
     let a4;
     a4 = GenericStruct { a: 1.0, b: 456 };
 
     let b4: f32 = a4.a;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let c4: usize = a4.b;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 
     let a5;
     a5 = GenericStruct::<_> { a: true, b: 456 };
 
     let b5: bool = a5.a;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let c5: usize = a5.b;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/generics10.rs b/gcc/testsuite/rust.test/compile/generics10.rs
index 6307b79..9526149 100644
--- a/gcc/testsuite/rust.test/compile/generics10.rs
+++ b/gcc/testsuite/rust.test/compile/generics10.rs
@@ -15,4 +15,5 @@ fn main() {
         b: true,
     };
     let b: Foo<i32> = test(a);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/generics12.rs b/gcc/testsuite/rust.test/compile/generics12.rs
index 0be8b0e..f31be58 100644
--- a/gcc/testsuite/rust.test/compile/generics12.rs
+++ b/gcc/testsuite/rust.test/compile/generics12.rs
@@ -13,4 +13,5 @@ impl GenericStruct<i32> {
 fn main() {
     let a: GenericStruct<i32> = GenericStruct::<i32>::new(123, 456);
     let aa: i32 = a.get();
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/generics2.rs b/gcc/testsuite/rust.test/compile/generics2.rs
index ee759dd..da0ab99 100644
--- a/gcc/testsuite/rust.test/compile/generics2.rs
+++ b/gcc/testsuite/rust.test/compile/generics2.rs
@@ -7,29 +7,39 @@ fn main() {
     a1 = Foo(1.0, false);
 
     let b1: f32 = a1.0;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let c1: bool = a1.1;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 
     let a2: GenericStruct<i8>;
     a2 = GenericStruct::<i8>(1, 456);
 
     let b2: i8 = a2.0;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let c2: usize = a2.1;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 
     let a3;
     a3 = GenericStruct::<i32>(123, 456);
 
     let b3: i32 = a3.0;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let c3: usize = a3.1;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 
     let a4;
     a4 = GenericStruct(1.0, 456);
 
     let b4: f32 = a4.0;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let c4: usize = a4.1;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 
     let a5;
     a5 = GenericStruct::<_>(true, 456);
 
     let b5: bool = a5.0;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let c5: usize = a5.1;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/generics3.rs b/gcc/testsuite/rust.test/compile/generics3.rs
index 0dc41c3..ceec8f7 100644
--- a/gcc/testsuite/rust.test/compile/generics3.rs
+++ b/gcc/testsuite/rust.test/compile/generics3.rs
@@ -6,8 +6,10 @@ fn main() {
     let a;
     a = test(123);
     let aa: i32 = a;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 
     let b;
     b = test::<u32>(456);
     let bb: u32 = b;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/generics4.rs b/gcc/testsuite/rust.test/compile/generics4.rs
index 81ac4e6..3ae3861 100644
--- a/gcc/testsuite/rust.test/compile/generics4.rs
+++ b/gcc/testsuite/rust.test/compile/generics4.rs
@@ -9,5 +9,7 @@ fn test<T>(a: T) -> Foo<T> {
 
 fn main() {
     let a: Foo<i32> = test(123);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let b: Foo<u32> = test(456);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/generics5.rs b/gcc/testsuite/rust.test/compile/generics5.rs
index 3d7f70d..b7f4302 100644
--- a/gcc/testsuite/rust.test/compile/generics5.rs
+++ b/gcc/testsuite/rust.test/compile/generics5.rs
@@ -4,5 +4,7 @@ fn test<T>(a: T) -> T {
 
 fn main() {
     let a: i32 = test(123);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let b: i32 = test(456);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/generics6.rs b/gcc/testsuite/rust.test/compile/generics6.rs
index da9f167..283a118 100644
--- a/gcc/testsuite/rust.test/compile/generics6.rs
+++ b/gcc/testsuite/rust.test/compile/generics6.rs
@@ -11,4 +11,5 @@ fn main() {
         b: true,
     };
     let b: i32 = a.a.0;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/generics7.rs b/gcc/testsuite/rust.test/compile/generics7.rs
index b534708..2e89ce1 100644
--- a/gcc/testsuite/rust.test/compile/generics7.rs
+++ b/gcc/testsuite/rust.test/compile/generics7.rs
@@ -9,4 +9,5 @@ fn main() {
     let a = Foo::<i32>(123);
     let b: Bar = Bar { a: a, b: true };
     let c: i32 = b.a.0;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/generics8.rs b/gcc/testsuite/rust.test/compile/generics8.rs
index ad5a1f4..036d855 100644
--- a/gcc/testsuite/rust.test/compile/generics8.rs
+++ b/gcc/testsuite/rust.test/compile/generics8.rs
@@ -8,8 +8,11 @@ impl<T> GenericStruct<T> {
 
 fn main() {
     let a: GenericStruct<i32> = GenericStruct::<i32>::new(123, 456);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 
     let b: GenericStruct<u32> = GenericStruct::<_>::new(123, 456);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 
     let c: GenericStruct<f32> = GenericStruct::new(123f32, 456);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/generics9.rs b/gcc/testsuite/rust.test/compile/generics9.rs
index 0399a62..307c34f 100644
--- a/gcc/testsuite/rust.test/compile/generics9.rs
+++ b/gcc/testsuite/rust.test/compile/generics9.rs
@@ -13,10 +13,13 @@ impl<T> GenericStruct<T> {
 fn main() {
     let a: GenericStruct<i32> = GenericStruct::<i32>::new(123, 456);
     let aa: i32 = a.get();
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 
     let b: GenericStruct<u32> = GenericStruct::<_>::new(123, 456);
     let bb: u32 = b.get();
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 
     let c: GenericStruct<f32> = GenericStruct::new(123f32, 456);
     let cc: f32 = c.get();
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/if_elif_else_expr1.rs b/gcc/testsuite/rust.test/compile/if_elif_else_expr1.rs
index eda6d17..65ed7f7 100644
--- a/gcc/testsuite/rust.test/compile/if_elif_else_expr1.rs
+++ b/gcc/testsuite/rust.test/compile/if_elif_else_expr1.rs
@@ -10,4 +10,5 @@ fn test(x: i32) -> i32 {
 
 fn main() {
     let a = test(1);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/impl_block3.rs b/gcc/testsuite/rust.test/compile/impl_block3.rs
index 3093a6c..78ec459 100644
--- a/gcc/testsuite/rust.test/compile/impl_block3.rs
+++ b/gcc/testsuite/rust.test/compile/impl_block3.rs
@@ -28,4 +28,5 @@ fn main() {
     let p1 = Point::origin();
     let p2 = Point::new(3.0, 4.0);
     let rect = Rectangle::from(p1, p2);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/implicit_returns1.rs b/gcc/testsuite/rust.test/compile/implicit_returns1.rs
index 49457c6..54cc8b3 100644
--- a/gcc/testsuite/rust.test/compile/implicit_returns1.rs
+++ b/gcc/testsuite/rust.test/compile/implicit_returns1.rs
@@ -55,11 +55,19 @@ fn test8() -> i32 {
 
 fn main() {
     let call1 = test1();
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let call2 = test2();
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let call3 = test3(3);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let call4 = test4(4);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let call5 = test5(5);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let call6 = test6(6);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let call7 = test7(7);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let call8 = test8();
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/infer_type1.rs b/gcc/testsuite/rust.test/compile/infer_type1.rs
index 38bd8ae..aabfcef 100644
--- a/gcc/testsuite/rust.test/compile/infer_type1.rs
+++ b/gcc/testsuite/rust.test/compile/infer_type1.rs
@@ -1,3 +1,4 @@
 fn main() {
     let array: [_; 2] = [111, 222];
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/integer_inference_var3.rs b/gcc/testsuite/rust.test/compile/integer_inference_var3.rs
index 858c5d3..582ae77 100644
--- a/gcc/testsuite/rust.test/compile/integer_inference_var3.rs
+++ b/gcc/testsuite/rust.test/compile/integer_inference_var3.rs
@@ -7,4 +7,5 @@ fn main() {
     param = 123;
 
     let a = test(param);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/integer_inference_var5.rs b/gcc/testsuite/rust.test/compile/integer_inference_var5.rs
index 6b97de5..051de1d 100644
--- a/gcc/testsuite/rust.test/compile/integer_inference_var5.rs
+++ b/gcc/testsuite/rust.test/compile/integer_inference_var5.rs
@@ -6,6 +6,7 @@ fn test(x: u32) -> u32 {
 
 fn main() {
     let x = TEST_CONST;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 
     let a = 1u32;
     let b = a;
@@ -20,4 +21,5 @@ fn main() {
     param = 123;
 
     let test_call = test(param);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/integer_types.rs b/gcc/testsuite/rust.test/compile/integer_types.rs
index 22a9164..95a7378 100644
--- a/gcc/testsuite/rust.test/compile/integer_types.rs
+++ b/gcc/testsuite/rust.test/compile/integer_types.rs
@@ -1,3 +1,5 @@
+// { dg-prune-output "warning: unused name" } as there are many of these expected.
+
 fn main() {
     let a1: i8 = 1i8;
     let a2: i16 = 2i16;
diff --git a/gcc/testsuite/rust.test/compile/literals1.rs b/gcc/testsuite/rust.test/compile/literals1.rs
index cd48e83..cf021e2 100644
--- a/gcc/testsuite/rust.test/compile/literals1.rs
+++ b/gcc/testsuite/rust.test/compile/literals1.rs
@@ -1,3 +1,5 @@
+// { dg-prune-output "warning: unused name" } as there are many of these expected.
+
 fn main() {
     let hex: i32 = 0xFF;
     let binary: i32 = 0b11110000;
diff --git a/gcc/testsuite/rust.test/compile/loop5.rs b/gcc/testsuite/rust.test/compile/loop5.rs
index 4004cd3..06f5f9e 100644
--- a/gcc/testsuite/rust.test/compile/loop5.rs
+++ b/gcc/testsuite/rust.test/compile/loop5.rs
@@ -4,6 +4,7 @@ fn main() {
 
     // first number in Fibonacci sequence over 10:
     let _fib = loop {
+        // { dg-bogus "unused name" "#361" { xfail *-*-* } .-1 }
         if b > 10 {
             break b;
         }
diff --git a/gcc/testsuite/rust.test/compile/loop7.rs b/gcc/testsuite/rust.test/compile/loop7.rs
index 0cd8445..647df13 100644
--- a/gcc/testsuite/rust.test/compile/loop7.rs
+++ b/gcc/testsuite/rust.test/compile/loop7.rs
@@ -3,6 +3,7 @@ fn main() {
     let mut b = 1;
 
     let _fib = loop {
+        // { dg-bogus "unused name" "#361" { xfail *-*-* } .-1 }
         if (a % 2 == 0) {
             continue;
         }
diff --git a/gcc/testsuite/rust.test/compile/methods1.rs b/gcc/testsuite/rust.test/compile/methods1.rs
index cffa02e..df3663f 100644
--- a/gcc/testsuite/rust.test/compile/methods1.rs
+++ b/gcc/testsuite/rust.test/compile/methods1.rs
@@ -36,4 +36,5 @@ fn main() {
     let rect = Rectangle::from(p1, p2);
 
     let sum = rect.sum_x();
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/methods2.rs b/gcc/testsuite/rust.test/compile/methods2.rs
index 96a3211..72ba29c 100644
--- a/gcc/testsuite/rust.test/compile/methods2.rs
+++ b/gcc/testsuite/rust.test/compile/methods2.rs
@@ -30,6 +30,7 @@ fn main() {
     let rect = Rectangle::from(p1, p2);
 
     let sum = rect.sum_x();
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
 
 impl Rectangle {
diff --git a/gcc/testsuite/rust.test/compile/methods3.rs b/gcc/testsuite/rust.test/compile/methods3.rs
index a71d045..b0cb78f 100644
--- a/gcc/testsuite/rust.test/compile/methods3.rs
+++ b/gcc/testsuite/rust.test/compile/methods3.rs
@@ -36,6 +36,8 @@ fn main() {
     let rect = Rectangle::from(p1, p2);
 
     let sum = rect.sum_x();
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     // multiple MethodCallExpr were causing issue #310
     let sum = rect.sum_x();
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/nested_struct1.rs b/gcc/testsuite/rust.test/compile/nested_struct1.rs
index 3880be0..56ce053 100644
--- a/gcc/testsuite/rust.test/compile/nested_struct1.rs
+++ b/gcc/testsuite/rust.test/compile/nested_struct1.rs
@@ -14,4 +14,5 @@ fn main() {
     let rect = Rectangle { p1, p2 };
 
     let a = rect.p1.x;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/parameter_usage1.rs b/gcc/testsuite/rust.test/compile/parameter_usage1.rs
index 7bba6c6..448e960 100644
--- a/gcc/testsuite/rust.test/compile/parameter_usage1.rs
+++ b/gcc/testsuite/rust.test/compile/parameter_usage1.rs
@@ -4,4 +4,5 @@ fn test(a: i32, b: i32) -> i32 {
 
 fn main() {
     let a = test(1, 4);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/parens1.rs b/gcc/testsuite/rust.test/compile/parens1.rs
index 33d9d86..795eb96 100644
--- a/gcc/testsuite/rust.test/compile/parens1.rs
+++ b/gcc/testsuite/rust.test/compile/parens1.rs
@@ -1,4 +1,5 @@
 fn main() {
     let a = 123;
     let b = a + (a * 2);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/recursive_fn1.rs b/gcc/testsuite/rust.test/compile/recursive_fn1.rs
index 89c21d0..e13b41f 100644
--- a/gcc/testsuite/rust.test/compile/recursive_fn1.rs
+++ b/gcc/testsuite/rust.test/compile/recursive_fn1.rs
@@ -8,4 +8,5 @@ fn gcd(x: i32, y: i32) -> i32 {
 
 fn main() {
     let a = gcd(100, 5);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/scoping1.rs b/gcc/testsuite/rust.test/compile/scoping1.rs
index 74af41e..8bc8ede 100644
--- a/gcc/testsuite/rust.test/compile/scoping1.rs
+++ b/gcc/testsuite/rust.test/compile/scoping1.rs
@@ -7,4 +7,5 @@ fn main() {
         }
     }
     let x = x + 1;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/shadow1.rs b/gcc/testsuite/rust.test/compile/shadow1.rs
index 3cb1ec5..b60e793 100644
--- a/gcc/testsuite/rust.test/compile/shadow1.rs
+++ b/gcc/testsuite/rust.test/compile/shadow1.rs
@@ -1,5 +1,6 @@
 fn main() {
     let mut x = 5;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let mut x;
     x = true;
 }
diff --git a/gcc/testsuite/rust.test/compile/shadow2.rs b/gcc/testsuite/rust.test/compile/shadow2.rs
index fbac8c0..161dc38 100644
--- a/gcc/testsuite/rust.test/compile/shadow2.rs
+++ b/gcc/testsuite/rust.test/compile/shadow2.rs
@@ -1,4 +1,5 @@
 fn main() {
     let x = 1;
     let x = x + 1;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/static_function.rs b/gcc/testsuite/rust.test/compile/static_function.rs
index 7a564af..8e3a379 100644
--- a/gcc/testsuite/rust.test/compile/static_function.rs
+++ b/gcc/testsuite/rust.test/compile/static_function.rs
@@ -4,4 +4,5 @@ fn test(x: i32) -> i32 {
 
 fn main() {
     let call_test = test(1);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/static_var1.rs b/gcc/testsuite/rust.test/compile/static_var1.rs
index 8464f41..5be0e75 100644
--- a/gcc/testsuite/rust.test/compile/static_var1.rs
+++ b/gcc/testsuite/rust.test/compile/static_var1.rs
@@ -2,4 +2,5 @@ static x:i32 = 3;
 
 fn main() {
     let y = x +1;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/struct_access1.rs b/gcc/testsuite/rust.test/compile/struct_access1.rs
index bc12b93..ec85d28 100644
--- a/gcc/testsuite/rust.test/compile/struct_access1.rs
+++ b/gcc/testsuite/rust.test/compile/struct_access1.rs
@@ -6,5 +6,7 @@ struct Foo {
 fn main() {
     let struct_test = Foo { one: 1, two: 2 };
     let a = struct_test.one;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let b = struct_test.two;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/struct_base_init_1.rs b/gcc/testsuite/rust.test/compile/struct_base_init_1.rs
index 3c0b24a..781265a 100644
--- a/gcc/testsuite/rust.test/compile/struct_base_init_1.rs
+++ b/gcc/testsuite/rust.test/compile/struct_base_init_1.rs
@@ -9,4 +9,5 @@ fn foo() -> Foo {
 
 fn main() {
     let _f = Foo { a: 10, ..foo() };
+    // { dg-bogus "unused name" "#361" { xfail *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/struct_init.rs b/gcc/testsuite/rust.test/compile/struct_init.rs
index 6081476..be0b963 100644
--- a/gcc/testsuite/rust.test/compile/struct_init.rs
+++ b/gcc/testsuite/rust.test/compile/struct_init.rs
@@ -5,4 +5,5 @@ struct Foo {
 
 fn main() {
     let struct_test = Foo { one: 1, two: 2 };
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/struct_init_2.rs b/gcc/testsuite/rust.test/compile/struct_init_2.rs
index 8d210b8..d7040d3 100644
--- a/gcc/testsuite/rust.test/compile/struct_init_2.rs
+++ b/gcc/testsuite/rust.test/compile/struct_init_2.rs
@@ -2,4 +2,5 @@ struct Foo(f32, f32);
 
 fn main() {
     let a = Foo { 0: 10.0, 1: 20.0 };
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/struct_init_3.rs b/gcc/testsuite/rust.test/compile/struct_init_3.rs
index fb1e58e..5e52d09 100644
--- a/gcc/testsuite/rust.test/compile/struct_init_3.rs
+++ b/gcc/testsuite/rust.test/compile/struct_init_3.rs
@@ -7,4 +7,5 @@ fn main() {
     let a = 1;
     let b = 2;
     let c = Foo { a, b };
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/struct_init_4.rs b/gcc/testsuite/rust.test/compile/struct_init_4.rs
index 2cc8a19..57b6bd4 100644
--- a/gcc/testsuite/rust.test/compile/struct_init_4.rs
+++ b/gcc/testsuite/rust.test/compile/struct_init_4.rs
@@ -6,4 +6,5 @@ struct Foo {
 fn main() {
     let a = Foo { a: 1, b: 2 };
     let b = Foo { a: 3, b: 4, ..a };
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/struct_init_5.rs b/gcc/testsuite/rust.test/compile/struct_init_5.rs
index c79ea71..891f645 100644
--- a/gcc/testsuite/rust.test/compile/struct_init_5.rs
+++ b/gcc/testsuite/rust.test/compile/struct_init_5.rs
@@ -6,4 +6,5 @@ struct Foo {
 fn main() {
     let a = Foo { a: 1, b: 2 };
     let b = Foo { ..a };
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/struct_init_6.rs b/gcc/testsuite/rust.test/compile/struct_init_6.rs
index 51b90bc..e7f8a12 100644
--- a/gcc/testsuite/rust.test/compile/struct_init_6.rs
+++ b/gcc/testsuite/rust.test/compile/struct_init_6.rs
@@ -6,4 +6,5 @@ struct Foo {
 fn main() {
     let a = Foo { a: 1, b: 2 };
     let b = Foo { a: 1, ..a };
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/struct_init_7.rs b/gcc/testsuite/rust.test/compile/struct_init_7.rs
index 615eae7..a8c8050 100644
--- a/gcc/testsuite/rust.test/compile/struct_init_7.rs
+++ b/gcc/testsuite/rust.test/compile/struct_init_7.rs
@@ -6,4 +6,5 @@ struct Foo {
 fn main() {
     let a = Foo { a: 1, b: 2f32 };
     let b = Foo { b: 4f32, ..a };
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/struct_init_8.rs b/gcc/testsuite/rust.test/compile/struct_init_8.rs
index e62f40a..411ff7d 100644
--- a/gcc/testsuite/rust.test/compile/struct_init_8.rs
+++ b/gcc/testsuite/rust.test/compile/struct_init_8.rs
@@ -3,4 +3,5 @@ struct Foo(f32, i32);
 fn main() {
     let a = Foo { 1: 1, 0: 2f32 };
     let b = Foo { ..a };
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/tuple1.rs b/gcc/testsuite/rust.test/compile/tuple1.rs
index 8b89601..9e6f613 100644
--- a/gcc/testsuite/rust.test/compile/tuple1.rs
+++ b/gcc/testsuite/rust.test/compile/tuple1.rs
@@ -1,5 +1,6 @@
 fn main() {
     let a: (i32, bool) = (123, true);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let b;
     b = (456, 5f32);
 }
diff --git a/gcc/testsuite/rust.test/compile/tuple2.rs b/gcc/testsuite/rust.test/compile/tuple2.rs
index 51333d8..ab3d0b8 100644
--- a/gcc/testsuite/rust.test/compile/tuple2.rs
+++ b/gcc/testsuite/rust.test/compile/tuple2.rs
@@ -1,4 +1,5 @@
 fn main() {
     let a = 123;
     let b = (a,);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/tuple_struct1.rs b/gcc/testsuite/rust.test/compile/tuple_struct1.rs
index 65e29f7..0ac19b1 100644
--- a/gcc/testsuite/rust.test/compile/tuple_struct1.rs
+++ b/gcc/testsuite/rust.test/compile/tuple_struct1.rs
@@ -2,4 +2,5 @@ struct Foo(i32, i32, bool);
 
 fn main() {
     let a = Foo(1, 2, true);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/type-alias2.rs b/gcc/testsuite/rust.test/compile/type-alias2.rs
index b1ac205..a3e3f4e 100644
--- a/gcc/testsuite/rust.test/compile/type-alias2.rs
+++ b/gcc/testsuite/rust.test/compile/type-alias2.rs
@@ -2,5 +2,7 @@ type x = u32;
 
 fn main() {
     let x: x = 1;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let y: x = 2;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/type_infer1.rs b/gcc/testsuite/rust.test/compile/type_infer1.rs
index bc4b09a..b6502b5 100644
--- a/gcc/testsuite/rust.test/compile/type_infer1.rs
+++ b/gcc/testsuite/rust.test/compile/type_infer1.rs
@@ -9,11 +9,14 @@ fn test(x: i32) -> i32 {
 
 fn main() {
     let logical: bool = true;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let an_integer = 5;
     let mut default_integer = 7;
 
     default_integer = 1 + an_integer;
 
     let call_test = test(1);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let struct_test = Foo { one: 1, two: 2 };
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/type_infer2.rs b/gcc/testsuite/rust.test/compile/type_infer2.rs
index 614c67d..dcddda4 100644
--- a/gcc/testsuite/rust.test/compile/type_infer2.rs
+++ b/gcc/testsuite/rust.test/compile/type_infer2.rs
@@ -5,4 +5,5 @@ fn test(x: i32) -> i32 {
 fn main() {
     let an_integer = 5;
     let call_test = test(an_integer + 1);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/type_infer3.rs b/gcc/testsuite/rust.test/compile/type_infer3.rs
index b20b565..303dd3d 100644
--- a/gcc/testsuite/rust.test/compile/type_infer3.rs
+++ b/gcc/testsuite/rust.test/compile/type_infer3.rs
@@ -10,4 +10,5 @@ fn main() {
     x = 1;
 
     let call_test = test(1);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/type_infer4.rs b/gcc/testsuite/rust.test/compile/type_infer4.rs
index 8e123e2..77a919f 100644
--- a/gcc/testsuite/rust.test/compile/type_infer4.rs
+++ b/gcc/testsuite/rust.test/compile/type_infer4.rs
@@ -3,7 +3,9 @@ fn main() {
     let xy = [6, 7, 8];
 
     let a = xs[0];
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let b = xy[2];
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let mut c;
     c = xs[0];
 }
diff --git a/gcc/testsuite/rust.test/compile/type_infer5.rs b/gcc/testsuite/rust.test/compile/type_infer5.rs
index 65c7058..1bccb4c 100644
--- a/gcc/testsuite/rust.test/compile/type_infer5.rs
+++ b/gcc/testsuite/rust.test/compile/type_infer5.rs
@@ -8,4 +8,5 @@ fn main() {
     a = Foo { a: 1, b: 2 };
 
     let b = a.a;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/type_infer6.rs b/gcc/testsuite/rust.test/compile/type_infer6.rs
index f6eac9e..6f5863f 100644
--- a/gcc/testsuite/rust.test/compile/type_infer6.rs
+++ b/gcc/testsuite/rust.test/compile/type_infer6.rs
@@ -6,7 +6,9 @@ fn main() {
     let a;
     a = 1;
     let b = test(a);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 
     let c = 1;
     let d = test(c + 1);
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/unary_operators.rs b/gcc/testsuite/rust.test/compile/unary_operators.rs
index 1ed9666..9be729c 100644
--- a/gcc/testsuite/rust.test/compile/unary_operators.rs
+++ b/gcc/testsuite/rust.test/compile/unary_operators.rs
@@ -1,3 +1,5 @@
+// { dg-prune-output "warning: unused name" } as there are many of these expected.
+
 fn main() {
     let a: i32 = -1;
     let b: i32 = 3 - -1;
diff --git a/gcc/testsuite/rust.test/compile/unit_type1.rs b/gcc/testsuite/rust.test/compile/unit_type1.rs
index ea1ebb3..d5f7357 100644
--- a/gcc/testsuite/rust.test/compile/unit_type1.rs
+++ b/gcc/testsuite/rust.test/compile/unit_type1.rs
@@ -1,5 +1,6 @@
 fn main() {
     let a: () = ();
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 
     let b;
     b = ();
diff --git a/gcc/testsuite/rust.test/compile/unused.rs b/gcc/testsuite/rust.test/compile/unused.rs
index c5ba0a9..a4987b5 100644
--- a/gcc/testsuite/rust.test/compile/unused.rs
+++ b/gcc/testsuite/rust.test/compile/unused.rs
@@ -1,8 +1,9 @@
-
+// { dg-warning "function is never used: `bar`" "" { target *-*-* } .+1 }
 fn bar() {
     foo();
 }
 
+// { dg-warning "function is never used: `foo`" "" { target *-*-* } .+1 }
 fn foo() {
     bar();
 }
diff --git a/gcc/testsuite/rust.test/compile/unused1.rs b/gcc/testsuite/rust.test/compile/unused1.rs
index cb50188..3b4873c 100644
--- a/gcc/testsuite/rust.test/compile/unused1.rs
+++ b/gcc/testsuite/rust.test/compile/unused1.rs
@@ -3,10 +3,14 @@ fn test() -> i32 {
 }
 
 fn unused() -> i32 {
+    // { dg-warning "function is never used: `unused`" "" { target *-*-* } .-1 }
+    // { dg-warning "unused name" "" { target *-*-* } .-2 }
     2
 }
 
 fn main() {
     let a = 1;
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
     let b = test();
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/compile/usize1.rs b/gcc/testsuite/rust.test/compile/usize1.rs
index 0df0a85..ba1d5c6 100644
--- a/gcc/testsuite/rust.test/compile/usize1.rs
+++ b/gcc/testsuite/rust.test/compile/usize1.rs
@@ -2,4 +2,5 @@ fn main() {
     let a = [1, 2, 3];
     let b: usize = 1;
     let c = a[b];
+    // { dg-warning "unused name" "" { target *-*-* } .-1 }
 }
diff --git a/gcc/testsuite/rust.test/execute/execute.exp b/gcc/testsuite/rust.test/execute/execute.exp
index d4e9949..f4deaa1 100644
--- a/gcc/testsuite/rust.test/execute/execute.exp
+++ b/gcc/testsuite/rust.test/execute/execute.exp
@@ -28,7 +28,7 @@ dg-init
 set saved-dg-do-what-default ${dg-do-what-default}
 
 set dg-do-what-default "run"
-gcc-dg-runtest [lsort [glob -nocomplain $srcdir/$subdir/*.rs]] "" "-w"
+gcc-dg-runtest [lsort [glob -nocomplain $srcdir/$subdir/*.rs]] "" ""
 set dg-do-what-default ${saved-dg-do-what-default}
 
 # All done.
diff --git a/gcc/testsuite/rust.test/xfail_compile/implicit_returns_err2.rs b/gcc/testsuite/rust.test/xfail_compile/implicit_returns_err2.rs
index 3b9a402..75f4db4 100644
--- a/gcc/testsuite/rust.test/xfail_compile/implicit_returns_err2.rs
+++ b/gcc/testsuite/rust.test/xfail_compile/implicit_returns_err2.rs
@@ -2,6 +2,7 @@
 
 fn test(x: i32) -> i32 {
     return 1;
+    // { dg-warning "unreachable expression" "" { target *-*-* } .+1 }
     true
 }
 
diff --git a/gcc/testsuite/rust.test/xfail_compile/xfail_compile.exp b/gcc/testsuite/rust.test/xfail_compile/xfail_compile.exp
index 68453a1..1936587 100644
--- a/gcc/testsuite/rust.test/xfail_compile/xfail_compile.exp
+++ b/gcc/testsuite/rust.test/xfail_compile/xfail_compile.exp
@@ -29,7 +29,7 @@ dg-init
 set saved-dg-do-what-default ${dg-do-what-default}
 
 set dg-do-what-default "compile"
-dg-runtest [lsort [glob -nocomplain $srcdir/$subdir/*.rs]] "" "-w"
+dg-runtest [lsort [glob -nocomplain $srcdir/$subdir/*.rs]] "" ""
 set dg-do-what-default ${saved-dg-do-what-default}
 
 # All done.