diff --git a/library/core/src/macros/mod.rs b/library/core/src/macros/mod.rs
index 7c93c93b4a019..e3bb0c1102df4 100644
--- a/library/core/src/macros/mod.rs
+++ b/library/core/src/macros/mod.rs
@@ -38,11 +38,11 @@ macro_rules! assert_eq {
         match (&$left, &$right) {
             (left_val, right_val) => {
                 if !(*left_val == *right_val) {
-                    let kind = $crate::panicking::AssertKind::Eq;
+                    let assert = $crate::concat!($crate::stringify!($left), " == ", $crate::stringify!($right));
                     // The reborrows below are intentional. Without them, the stack slot for the
                     // borrow is initialized even before the values are compared, leading to a
                     // noticeable slow down.
-                    $crate::panicking::assert_failed(kind, &*left_val, &*right_val, $crate::option::Option::None);
+                    $crate::panicking::assert_failed(assert, &*left_val, &*right_val, $crate::option::Option::None);
                 }
             }
         }
@@ -51,11 +51,11 @@ macro_rules! assert_eq {
         match (&$left, &$right) {
             (left_val, right_val) => {
                 if !(*left_val == *right_val) {
-                    let kind = $crate::panicking::AssertKind::Eq;
+                    let assert = $crate::concat!($crate::stringify!($left), " == ", $crate::stringify!($right));
                     // The reborrows below are intentional. Without them, the stack slot for the
                     // borrow is initialized even before the values are compared, leading to a
                     // noticeable slow down.
-                    $crate::panicking::assert_failed(kind, &*left_val, &*right_val, $crate::option::Option::Some($crate::format_args!($($arg)+)));
+                    $crate::panicking::assert_failed(assert, &*left_val, &*right_val, $crate::option::Option::Some($crate::format_args!($($arg)+)));
                 }
             }
         }
@@ -88,11 +88,11 @@ macro_rules! assert_ne {
         match (&$left, &$right) {
             (left_val, right_val) => {
                 if *left_val == *right_val {
-                    let kind = $crate::panicking::AssertKind::Ne;
+                    let assert = $crate::concat!($crate::stringify!($left), " != ", $crate::stringify!($right));
                     // The reborrows below are intentional. Without them, the stack slot for the
                     // borrow is initialized even before the values are compared, leading to a
                     // noticeable slow down.
-                    $crate::panicking::assert_failed(kind, &*left_val, &*right_val, $crate::option::Option::None);
+                    $crate::panicking::assert_failed(assert, &*left_val, &*right_val, $crate::option::Option::None);
                 }
             }
         }
@@ -101,11 +101,11 @@ macro_rules! assert_ne {
         match (&($left), &($right)) {
             (left_val, right_val) => {
                 if *left_val == *right_val {
-                    let kind = $crate::panicking::AssertKind::Ne;
+                    let assert = $crate::concat!($crate::stringify!($left), " != ", $crate::stringify!($right));
                     // The reborrows below are intentional. Without them, the stack slot for the
                     // borrow is initialized even before the values are compared, leading to a
                     // noticeable slow down.
-                    $crate::panicking::assert_failed(kind, &*left_val, &*right_val, $crate::option::Option::Some($crate::format_args!($($arg)+)));
+                    $crate::panicking::assert_failed(assert, &*left_val, &*right_val, $crate::option::Option::Some($crate::format_args!($($arg)+)));
                 }
             }
         }
@@ -146,10 +146,12 @@ pub macro assert_matches {
         match $left {
             $( $pattern )|+ $( if $guard )? => {}
             ref left_val => {
+                let assert = $crate::concat!($crate::stringify!($left), " matches ", $crate::stringify!($($pattern)|+ $(if $guard)?));
                 $crate::panicking::assert_matches_failed(
                     left_val,
                     $crate::stringify!($($pattern)|+ $(if $guard)?),
-                    $crate::option::Option::None
+                    $crate::option::Option::None,
+                    assert,
                 );
             }
         }
@@ -158,10 +160,12 @@ pub macro assert_matches {
         match $left {
             $( $pattern )|+ $( if $guard )? => {}
             ref left_val => {
+                let assert = $crate::concat!($crate::stringify!($left), " matches ", $crate::stringify!($($pattern)|+ $(if $guard)?));
                 $crate::panicking::assert_matches_failed(
                     left_val,
                     $crate::stringify!($($pattern)|+ $(if $guard)?),
-                    $crate::option::Option::Some($crate::format_args!($($arg)+))
+                    $crate::option::Option::Some($crate::format_args!($($arg)+)),
+                    assert,
                 );
             }
         }
diff --git a/library/core/src/panicking.rs b/library/core/src/panicking.rs
index 81be3fb22eec4..304dc214b1a13 100644
--- a/library/core/src/panicking.rs
+++ b/library/core/src/panicking.rs
@@ -202,21 +202,13 @@ pub const fn const_panic_fmt(fmt: fmt::Arguments<'_>) -> ! {
     }
 }
 
-#[derive(Debug)]
-#[doc(hidden)]
-pub enum AssertKind {
-    Eq,
-    Ne,
-    Match,
-}
-
 /// Internal function for `assert_eq!` and `assert_ne!` macros
 #[cfg_attr(not(feature = "panic_immediate_abort"), inline(never), cold)]
 #[cfg_attr(feature = "panic_immediate_abort", inline)]
 #[track_caller]
 #[doc(hidden)]
 pub fn assert_failed<T, U>(
-    kind: AssertKind,
+    assert_msg: &'static str,
     left: &T,
     right: &U,
     args: Option<fmt::Arguments<'_>>,
@@ -225,7 +217,7 @@ where
     T: fmt::Debug + ?Sized,
     U: fmt::Debug + ?Sized,
 {
-    assert_failed_inner(kind, &left, &right, args)
+    assert_failed_inner(assert_msg, &left, &right, args)
 }
 
 /// Internal function for `assert_match!`
@@ -237,6 +229,7 @@ pub fn assert_matches_failed<T: fmt::Debug + ?Sized>(
     left: &T,
     right: &str,
     args: Option<fmt::Arguments<'_>>,
+    assert_msg: &'static str,
 ) -> ! {
     // The pattern is a string so it can be displayed directly.
     struct Pattern<'a>(&'a str);
@@ -245,7 +238,7 @@ pub fn assert_matches_failed<T: fmt::Debug + ?Sized>(
             f.write_str(self.0)
         }
     }
-    assert_failed_inner(AssertKind::Match, &left, &Pattern(right), args);
+    assert_failed_inner(assert_msg, &left, &Pattern(right), args);
 }
 
 /// Non-generic version of the above functions, to avoid code bloat.
@@ -253,29 +246,22 @@ pub fn assert_matches_failed<T: fmt::Debug + ?Sized>(
 #[cfg_attr(feature = "panic_immediate_abort", inline)]
 #[track_caller]
 fn assert_failed_inner(
-    kind: AssertKind,
+    assert_msg: &'static str,
     left: &dyn fmt::Debug,
     right: &dyn fmt::Debug,
     args: Option<fmt::Arguments<'_>>,
 ) -> ! {
-    let op = match kind {
-        AssertKind::Eq => "==",
-        AssertKind::Ne => "!=",
-        AssertKind::Match => "matches",
-    };
-
     match args {
         Some(args) => panic!(
-            r#"assertion failed: `(left {} right)`
-  left: `{:?}`,
- right: `{:?}`: {}"#,
-            op, left, right, args
+            r#"assertion failed: `{assert_msg}`
+ error: {args}
+  left: `{left:?}`
+ right: `{right:?}`"#
         ),
         None => panic!(
-            r#"assertion failed: `(left {} right)`
-  left: `{:?}`,
- right: `{:?}`"#,
-            op, left, right,
+            r#"assertion failed: `{assert_msg}`
+  left: `{left:?}`
+ right: `{right:?}`"#
         ),
     }
 }
diff --git a/library/std/src/panicking.rs b/library/std/src/panicking.rs
index a46a29cbad608..6bcbcb6e800cf 100644
--- a/library/std/src/panicking.rs
+++ b/library/std/src/panicking.rs
@@ -257,7 +257,11 @@ fn default_hook(info: &PanicInfo<'_>) {
     let name = thread.as_ref().and_then(|t| t.name()).unwrap_or("<unnamed>");
 
     let write = |err: &mut dyn crate::io::Write| {
-        let _ = writeln!(err, "thread '{name}' panicked at '{msg}', {location}");
+        if msg.contains('\n') {
+            let _ = writeln!(err, "thread '{name}' panicked at {location}:\n{msg}");
+        } else {
+            let _ = writeln!(err, "thread '{name}' panicked at '{msg}', {location}");
+        }
 
         static FIRST_PANIC: AtomicBool = AtomicBool::new(true);
 
diff --git a/src/tools/clippy/clippy_utils/src/macros.rs b/src/tools/clippy/clippy_utils/src/macros.rs
index 62d388a5ece8d..9273bdbb5bdc5 100644
--- a/src/tools/clippy/clippy_utils/src/macros.rs
+++ b/src/tools/clippy/clippy_utils/src/macros.rs
@@ -238,6 +238,7 @@ impl<'a> PanicExpn<'a> {
             "assert_failed" => {
                 // It should have 4 arguments in total (we already matched with the first argument,
                 // so we're just checking for 3)
+                // Since Rust 1.70, `assert_failed` has two additional args.
                 if rest.len() != 3 {
                     return None;
                 }
diff --git a/tests/mir-opt/issue_99325.main.built.after.mir b/tests/mir-opt/issue_99325.main.built.after.mir
index f0c9ef419bd89..483c45e60de21 100644
--- a/tests/mir-opt/issue_99325.main.built.after.mir
+++ b/tests/mir-opt/issue_99325.main.built.after.mir
@@ -21,7 +21,7 @@ fn main() -> () {
     let mut _13: &&[u8; 4];              // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
     let mut _14: !;                      // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
     let _16: !;                          // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-    let mut _17: core::panicking::AssertKind; // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
+    let mut _17: &str;                   // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
     let mut _18: &&[u8];                 // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
     let _19: &&[u8];                     // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
     let mut _20: &&[u8; 4];              // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
@@ -41,7 +41,7 @@ fn main() -> () {
     let mut _34: &&[u8; 4];              // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
     let mut _35: !;                      // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
     let _37: !;                          // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-    let mut _38: core::panicking::AssertKind; // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
+    let mut _38: &str;                   // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
     let mut _39: &&[u8];                 // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
     let _40: &&[u8];                     // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
     let mut _41: &&[u8; 4];              // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
@@ -50,17 +50,17 @@ fn main() -> () {
     scope 1 {
         debug left_val => _8;            // in scope 1 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         debug right_val => _9;           // in scope 1 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-        let _15: core::panicking::AssertKind; // in scope 1 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
+        let _15: &str;                   // in scope 1 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         scope 2 {
-            debug kind => _15;           // in scope 2 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
+            debug assert => _15;         // in scope 2 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         }
     }
     scope 3 {
         debug left_val => _29;           // in scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         debug right_val => _30;          // in scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-        let _36: core::panicking::AssertKind; // in scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
+        let _36: &str;                   // in scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         scope 4 {
-            debug kind => _36;           // in scope 4 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
+            debug assert => _36;         // in scope 4 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         }
     }
 
@@ -114,11 +114,14 @@ fn main() -> () {
 
     bb3: {
         StorageLive(_15);                // scope 1 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-        _15 = core::panicking::AssertKind::Eq; // scope 1 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
+        _15 = const "function_with_bytes::<b\"AAAA\">() == &[0x41, 0x41, 0x41, 0x41]"; // scope 1 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
+                                         // mir::Constant
+                                         // + span: $SRC_DIR/core/src/macros/mod.rs:LL:COL
+                                         // + literal: Const { ty: &str, val: Value(Slice(..)) }
         FakeRead(ForLet(None), _15);     // scope 1 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         StorageLive(_16);                // scope 2 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         StorageLive(_17);                // scope 2 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-        _17 = move _15;                  // scope 2 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
+        _17 = &(*_15);                   // scope 2 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         StorageLive(_18);                // scope 2 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         StorageLive(_19);                // scope 2 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         _19 = &(*_8);                    // scope 2 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
@@ -132,7 +135,7 @@ fn main() -> () {
         _16 = core::panicking::assert_failed::<&[u8], &[u8; 4]>(move _17, move _18, move _20, move _22) -> bb19; // scope 2 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
                                          // mir::Constant
                                          // + span: $SRC_DIR/core/src/macros/mod.rs:LL:COL
-                                         // + literal: Const { ty: for<'a, 'b, 'c> fn(core::panicking::AssertKind, &'a &[u8], &'b &[u8; 4], Option<Arguments<'c>>) -> ! {core::panicking::assert_failed::<&[u8], &[u8; 4]>}, val: Value(<ZST>) }
+                                         // + literal: Const { ty: for<'a, 'b, 'c> fn(&'static str, &'a &[u8], &'b &[u8; 4], Option<Arguments<'c>>) -> ! {core::panicking::assert_failed::<&[u8], &[u8; 4]>}, val: Value(<ZST>) }
     }
 
     bb4: {
@@ -223,11 +226,14 @@ fn main() -> () {
 
     bb12: {
         StorageLive(_36);                // scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-        _36 = core::panicking::AssertKind::Eq; // scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
+        _36 = const "function_with_bytes::<{ &[0x41, 0x41, 0x41, 0x41] }>() == b\"AAAA\""; // scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
+                                         // mir::Constant
+                                         // + span: $SRC_DIR/core/src/macros/mod.rs:LL:COL
+                                         // + literal: Const { ty: &str, val: Value(Slice(..)) }
         FakeRead(ForLet(None), _36);     // scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         StorageLive(_37);                // scope 4 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         StorageLive(_38);                // scope 4 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-        _38 = move _36;                  // scope 4 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
+        _38 = &(*_36);                   // scope 4 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         StorageLive(_39);                // scope 4 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         StorageLive(_40);                // scope 4 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         _40 = &(*_29);                   // scope 4 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
@@ -241,7 +247,7 @@ fn main() -> () {
         _37 = core::panicking::assert_failed::<&[u8], &[u8; 4]>(move _38, move _39, move _41, move _43) -> bb19; // scope 4 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
                                          // mir::Constant
                                          // + span: $SRC_DIR/core/src/macros/mod.rs:LL:COL
-                                         // + literal: Const { ty: for<'a, 'b, 'c> fn(core::panicking::AssertKind, &'a &[u8], &'b &[u8; 4], Option<Arguments<'c>>) -> ! {core::panicking::assert_failed::<&[u8], &[u8; 4]>}, val: Value(<ZST>) }
+                                         // + literal: Const { ty: for<'a, 'b, 'c> fn(&'static str, &'a &[u8], &'b &[u8; 4], Option<Arguments<'c>>) -> ! {core::panicking::assert_failed::<&[u8], &[u8; 4]>}, val: Value(<ZST>) }
     }
 
     bb13: {
diff --git a/tests/mir-opt/retag.array_casts.SimplifyCfg-elaborate-drops.after.mir b/tests/mir-opt/retag.array_casts.SimplifyCfg-elaborate-drops.after.mir
index 3b479710b4f2d..2e84e8d1e5750 100644
--- a/tests/mir-opt/retag.array_casts.SimplifyCfg-elaborate-drops.after.mir
+++ b/tests/mir-opt/retag.array_casts.SimplifyCfg-elaborate-drops.after.mir
@@ -24,7 +24,7 @@ fn array_casts() -> () {
     let mut _25: usize;                  // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
     let mut _26: !;                      // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
     let _28: !;                          // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-    let mut _29: core::panicking::AssertKind; // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
+    let mut _29: &str;                   // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
     let mut _30: &usize;                 // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
     let _31: &usize;                     // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
     let mut _32: &usize;                 // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
@@ -51,9 +51,9 @@ fn array_casts() -> () {
                     scope 7 {
                         debug left_val => _20; // in scope 7 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
                         debug right_val => _21; // in scope 7 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-                        let _27: core::panicking::AssertKind; // in scope 7 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
+                        let _27: &str;   // in scope 7 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
                         scope 8 {
-                            debug kind => _27; // in scope 8 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
+                            debug assert => _27; // in scope 8 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
                         }
                     }
                 }
@@ -148,10 +148,14 @@ fn array_casts() -> () {
 
     bb3: {
         StorageLive(_27);                // scope 7 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-        _27 = core::panicking::AssertKind::Eq; // scope 7 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
+        _27 = const "unsafe { *p.add(1) } == 1"; // scope 7 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
+                                         // mir::Constant
+                                         // + span: $SRC_DIR/core/src/macros/mod.rs:LL:COL
+                                         // + literal: Const { ty: &str, val: Value(Slice(..)) }
+        Retag(_27);                      // scope 7 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         StorageLive(_28);                // scope 8 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         StorageLive(_29);                // scope 8 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-        _29 = move _27;                  // scope 8 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
+        _29 = &(*_27);                   // scope 8 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         StorageLive(_30);                // scope 8 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         StorageLive(_31);                // scope 8 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         _31 = &(*_20);                   // scope 8 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
@@ -166,7 +170,7 @@ fn array_casts() -> () {
         _28 = core::panicking::assert_failed::<usize, usize>(move _29, move _30, move _32, move _34); // scope 8 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
                                          // mir::Constant
                                          // + span: $SRC_DIR/core/src/macros/mod.rs:LL:COL
-                                         // + literal: Const { ty: for<'a, 'b, 'c> fn(core::panicking::AssertKind, &'a usize, &'b usize, Option<Arguments<'c>>) -> ! {core::panicking::assert_failed::<usize, usize>}, val: Value(<ZST>) }
+                                         // + literal: Const { ty: for<'a, 'b, 'c> fn(&'static str, &'a usize, &'b usize, Option<Arguments<'c>>) -> ! {core::panicking::assert_failed::<usize, usize>}, val: Value(<ZST>) }
     }
 
     bb4: {
diff --git a/tests/ui/macros/assert-eq-macro-msg.rs b/tests/ui/macros/assert-eq-macro-msg.rs
index accbd2d1e7f50..7657d9c14375f 100644
--- a/tests/ui/macros/assert-eq-macro-msg.rs
+++ b/tests/ui/macros/assert-eq-macro-msg.rs
@@ -1,7 +1,5 @@
 // run-fail
-// error-pattern:panicked at 'assertion failed: `(left == right)`
-// error-pattern: left: `2`
-// error-pattern:right: `3`: 1 + 1 definitely should be 3'
+// check-run-results
 // ignore-emscripten no processes
 
 fn main() {
diff --git a/tests/ui/macros/assert-eq-macro-msg.run.stderr b/tests/ui/macros/assert-eq-macro-msg.run.stderr
new file mode 100644
index 0000000000000..3283734dcd4cd
--- /dev/null
+++ b/tests/ui/macros/assert-eq-macro-msg.run.stderr
@@ -0,0 +1,6 @@
+thread 'main' panicked at $DIR/assert-eq-macro-msg.rs:6:5:
+assertion failed: `1 + 1 == 3`
+ error: 1 + 1 definitely should be 3
+  left: `2`
+ right: `3`
+note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
diff --git a/tests/ui/macros/assert-eq-macro-panic.rs b/tests/ui/macros/assert-eq-macro-panic.rs
index 5e505c30b3503..72cf184afeaaf 100644
--- a/tests/ui/macros/assert-eq-macro-panic.rs
+++ b/tests/ui/macros/assert-eq-macro-panic.rs
@@ -1,7 +1,5 @@
 // run-fail
-// error-pattern:assertion failed: `(left == right)`
-// error-pattern: left: `14`
-// error-pattern:right: `15`
+// check-run-results
 // ignore-emscripten no processes
 
 fn main() {
diff --git a/tests/ui/macros/assert-eq-macro-panic.run.stderr b/tests/ui/macros/assert-eq-macro-panic.run.stderr
new file mode 100644
index 0000000000000..065576dd05286
--- /dev/null
+++ b/tests/ui/macros/assert-eq-macro-panic.run.stderr
@@ -0,0 +1,5 @@
+thread 'main' panicked at $DIR/assert-eq-macro-panic.rs:6:5:
+assertion failed: `14 == 15`
+  left: `14`
+ right: `15`
+note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
diff --git a/tests/ui/macros/assert-eq-macro-vars.rs b/tests/ui/macros/assert-eq-macro-vars.rs
new file mode 100644
index 0000000000000..18253bd4c73b3
--- /dev/null
+++ b/tests/ui/macros/assert-eq-macro-vars.rs
@@ -0,0 +1,8 @@
+// run-fail
+// check-run-results
+// ignore-emscripten no processes
+
+fn main() {
+    let var = 2;
+    assert_eq!(var * 2, 3);
+}
diff --git a/tests/ui/macros/assert-eq-macro-vars.run.stderr b/tests/ui/macros/assert-eq-macro-vars.run.stderr
new file mode 100644
index 0000000000000..09d70fd7425ea
--- /dev/null
+++ b/tests/ui/macros/assert-eq-macro-vars.run.stderr
@@ -0,0 +1,5 @@
+thread 'main' panicked at $DIR/assert-eq-macro-vars.rs:7:5:
+assertion failed: `var * 2 == 3`
+  left: `4`
+ right: `3`
+note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
diff --git a/tests/ui/macros/assert-matches-macro-msg.rs b/tests/ui/macros/assert-matches-macro-msg.rs
index fd8cd5a1a0566..8beb7346cf187 100644
--- a/tests/ui/macros/assert-matches-macro-msg.rs
+++ b/tests/ui/macros/assert-matches-macro-msg.rs
@@ -1,7 +1,5 @@
 // run-fail
-// error-pattern:panicked at 'assertion failed: `(left matches right)`
-// error-pattern: left: `2`
-// error-pattern:right: `3`: 1 + 1 definitely should be 3'
+// check-run-results
 // ignore-emscripten no processes
 
 #![feature(assert_matches)]
diff --git a/tests/ui/macros/assert-matches-macro-msg.run.stderr b/tests/ui/macros/assert-matches-macro-msg.run.stderr
new file mode 100644
index 0000000000000..2cfc4da8c7701
--- /dev/null
+++ b/tests/ui/macros/assert-matches-macro-msg.run.stderr
@@ -0,0 +1,6 @@
+thread 'main' panicked at $DIR/assert-matches-macro-msg.rs:10:5:
+assertion failed: `1 + 1 matches 3`
+ error: 1 + 1 definitely should be 3
+  left: `2`
+ right: `3`
+note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
diff --git a/tests/ui/macros/assert-ne-macro-msg.rs b/tests/ui/macros/assert-ne-macro-msg.rs
index fc0472b99b428..5ddf5527f82b4 100644
--- a/tests/ui/macros/assert-ne-macro-msg.rs
+++ b/tests/ui/macros/assert-ne-macro-msg.rs
@@ -1,7 +1,5 @@
 // run-fail
-// error-pattern:panicked at 'assertion failed: `(left != right)`
-// error-pattern: left: `2`
-// error-pattern:right: `2`: 1 + 1 definitely should not be 2'
+// check-run-results
 // ignore-emscripten no processes
 
 fn main() {
diff --git a/tests/ui/macros/assert-ne-macro-msg.run.stderr b/tests/ui/macros/assert-ne-macro-msg.run.stderr
new file mode 100644
index 0000000000000..15b3de651ea01
--- /dev/null
+++ b/tests/ui/macros/assert-ne-macro-msg.run.stderr
@@ -0,0 +1,6 @@
+thread 'main' panicked at $DIR/assert-ne-macro-msg.rs:6:5:
+assertion failed: `1 + 1 != 2`
+ error: 1 + 1 definitely should not be 2
+  left: `2`
+ right: `2`
+note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
diff --git a/tests/ui/macros/assert-ne-macro-panic.rs b/tests/ui/macros/assert-ne-macro-panic.rs
index 4f507d7b54d99..137b27ee9e121 100644
--- a/tests/ui/macros/assert-ne-macro-panic.rs
+++ b/tests/ui/macros/assert-ne-macro-panic.rs
@@ -1,7 +1,5 @@
 // run-fail
-// error-pattern:assertion failed: `(left != right)`
-// error-pattern: left: `14`
-// error-pattern:right: `14`
+// check-run-results
 // ignore-emscripten no processes
 
 fn main() {
diff --git a/tests/ui/macros/assert-ne-macro-panic.run.stderr b/tests/ui/macros/assert-ne-macro-panic.run.stderr
new file mode 100644
index 0000000000000..9216d2077e88f
--- /dev/null
+++ b/tests/ui/macros/assert-ne-macro-panic.run.stderr
@@ -0,0 +1,5 @@
+thread 'main' panicked at $DIR/assert-ne-macro-panic.rs:6:5:
+assertion failed: `14 != 14`
+  left: `14`
+ right: `14`
+note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
diff --git a/tests/ui/test-attrs/test-panic-abort-nocapture.run.stderr b/tests/ui/test-attrs/test-panic-abort-nocapture.run.stderr
index 727e9691c53a1..580aedff79077 100644
--- a/tests/ui/test-attrs/test-panic-abort-nocapture.run.stderr
+++ b/tests/ui/test-attrs/test-panic-abort-nocapture.run.stderr
@@ -1,9 +1,11 @@
-thread 'main' panicked at 'assertion failed: `(left == right)`
-  left: `2`,
- right: `4`', $DIR/test-panic-abort-nocapture.rs:33:5
+thread 'main' panicked at $DIR/test-panic-abort-nocapture.rs:33:5:
+assertion failed: `1 + 1 == 4`
+  left: `2`
+ right: `4`
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
-thread 'main' panicked at 'assertion failed: `(left == right)`
-  left: `2`,
- right: `4`', $DIR/test-panic-abort-nocapture.rs:27:5
+thread 'main' panicked at $DIR/test-panic-abort-nocapture.rs:27:5:
+assertion failed: `1 + 1 == 4`
+  left: `2`
+ right: `4`
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
 testing321
diff --git a/tests/ui/test-attrs/test-panic-abort.run.stdout b/tests/ui/test-attrs/test-panic-abort.run.stdout
index f608a8cdc5569..e83d6a091b0ed 100644
--- a/tests/ui/test-attrs/test-panic-abort.run.stdout
+++ b/tests/ui/test-attrs/test-panic-abort.run.stdout
@@ -16,9 +16,10 @@ hello, world
 testing123
 ---- it_fails stderr ----
 testing321
-thread 'main' panicked at 'assertion failed: `(left == right)`
-  left: `2`,
- right: `5`', $DIR/test-panic-abort.rs:34:5
+thread 'main' panicked at $DIR/test-panic-abort.rs:34:5:
+assertion failed: `1 + 1 == 5`
+  left: `2`
+ right: `5`
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace