diff --git a/src/test/ui/async-await/issues/issue-62097.nll.stderr b/src/test/ui/async-await/issues/issue-62097.nll.stderr
index 2a399540e52..ab10e5f1810 100644
--- a/src/test/ui/async-await/issues/issue-62097.nll.stderr
+++ b/src/test/ui/async-await/issues/issue-62097.nll.stderr
@@ -26,4 +26,5 @@ LL |         foo(|| self.bar()).await;
 
 error: aborting due to 2 previous errors
 
-For more information about this error, try `rustc --explain E0373`.
+Some errors have detailed explanations: E0373, E0521.
+For more information about an error, try `rustc --explain E0373`.
diff --git a/src/test/ui/impl-header-lifetime-elision/dyn-trait.nll.stderr b/src/test/ui/impl-header-lifetime-elision/dyn-trait.nll.stderr
index 8e660d6814c..d72435bc631 100644
--- a/src/test/ui/impl-header-lifetime-elision/dyn-trait.nll.stderr
+++ b/src/test/ui/impl-header-lifetime-elision/dyn-trait.nll.stderr
@@ -10,3 +10,4 @@ LL |     static_val(x);
 
 error: aborting due to previous error
 
+For more information about this error, try `rustc --explain E0521`.
diff --git a/src/test/ui/issues/issue-16683.nll.stderr b/src/test/ui/issues/issue-16683.nll.stderr
index b82b0b552e2..51d86eaf9e6 100644
--- a/src/test/ui/issues/issue-16683.nll.stderr
+++ b/src/test/ui/issues/issue-16683.nll.stderr
@@ -8,3 +8,4 @@ LL |         self.a();
 
 error: aborting due to previous error
 
+For more information about this error, try `rustc --explain E0521`.
diff --git a/src/test/ui/issues/issue-17758.nll.stderr b/src/test/ui/issues/issue-17758.nll.stderr
index 23557b4d956..075c141ed7a 100644
--- a/src/test/ui/issues/issue-17758.nll.stderr
+++ b/src/test/ui/issues/issue-17758.nll.stderr
@@ -8,3 +8,4 @@ LL |         self.foo();
 
 error: aborting due to previous error
 
+For more information about this error, try `rustc --explain E0521`.
diff --git a/src/test/ui/lifetimes/lifetime-bound-will-change-warning.nll.stderr b/src/test/ui/lifetimes/lifetime-bound-will-change-warning.nll.stderr
index 60420973e1e..57dab46df6b 100644
--- a/src/test/ui/lifetimes/lifetime-bound-will-change-warning.nll.stderr
+++ b/src/test/ui/lifetimes/lifetime-bound-will-change-warning.nll.stderr
@@ -22,3 +22,4 @@ LL |     lib::ref_obj(x)
 
 error: aborting due to 2 previous errors
 
+For more information about this error, try `rustc --explain E0521`.
diff --git a/src/test/ui/object-lifetime/object-lifetime-default-mybox.nll.stderr b/src/test/ui/object-lifetime/object-lifetime-default-mybox.nll.stderr
index d871eb5327d..42dae7e40db 100644
--- a/src/test/ui/object-lifetime/object-lifetime-default-mybox.nll.stderr
+++ b/src/test/ui/object-lifetime/object-lifetime-default-mybox.nll.stderr
@@ -23,3 +23,4 @@ LL |     load0(ss)
 
 error: aborting due to 2 previous errors
 
+For more information about this error, try `rustc --explain E0521`.
diff --git a/src/test/ui/regions/region-invariant-static-error-reporting.nll.stderr b/src/test/ui/regions/region-invariant-static-error-reporting.nll.stderr
index d941030d824..89a22adc8f0 100644
--- a/src/test/ui/regions/region-invariant-static-error-reporting.nll.stderr
+++ b/src/test/ui/regions/region-invariant-static-error-reporting.nll.stderr
@@ -11,3 +11,4 @@ LL |         x.unwrap()
 
 error: aborting due to previous error
 
+For more information about this error, try `rustc --explain E0521`.
diff --git a/src/test/ui/regions/regions-bounded-method-type-parameters-trait-bound.nll.stderr b/src/test/ui/regions/regions-bounded-method-type-parameters-trait-bound.nll.stderr
index 92a3942c916..ed7b17c207c 100644
--- a/src/test/ui/regions/regions-bounded-method-type-parameters-trait-bound.nll.stderr
+++ b/src/test/ui/regions/regions-bounded-method-type-parameters-trait-bound.nll.stderr
@@ -13,3 +13,4 @@ LL |     f.method(b);
 
 error: aborting due to previous error
 
+For more information about this error, try `rustc --explain E0521`.
diff --git a/src/test/ui/regions/regions-nested-fns.nll.stderr b/src/test/ui/regions/regions-nested-fns.nll.stderr
index 9d966486f98..60754f4c228 100644
--- a/src/test/ui/regions/regions-nested-fns.nll.stderr
+++ b/src/test/ui/regions/regions-nested-fns.nll.stderr
@@ -50,4 +50,5 @@ LL |         if false { return x; }
 
 error: aborting due to 4 previous errors
 
-For more information about this error, try `rustc --explain E0597`.
+Some errors have detailed explanations: E0521, E0597.
+For more information about an error, try `rustc --explain E0521`.
diff --git a/src/test/ui/suggestions/impl-on-dyn-trait-with-implicit-static-bound.nll.stderr b/src/test/ui/suggestions/impl-on-dyn-trait-with-implicit-static-bound.nll.stderr
index 697467dc3a6..6c235ae8f02 100644
--- a/src/test/ui/suggestions/impl-on-dyn-trait-with-implicit-static-bound.nll.stderr
+++ b/src/test/ui/suggestions/impl-on-dyn-trait-with-implicit-static-bound.nll.stderr
@@ -40,3 +40,4 @@ LL |         MyTrait::use_self(val)
 
 error: aborting due to 4 previous errors
 
+For more information about this error, try `rustc --explain E0521`.