Rollup merge of #66880 - aDotInTheVoid:add-E0203-long, r=GuillaumeGomez

Add long error code explanation message for E0203

Addressed some of #61137

r? @GuillaumeGomez

1 files changed, 18 insertions, 0 deletions

diff --git a/src/librustc_error_codes/error_codes/E0203.md b/src/librustc_error_codes/error_codes/E0203.md
new file mode 100644
index 00000000000..1edb519275f
--- /dev/null
+++ b/src/librustc_error_codes/error_codes/E0203.md
@@ -0,0 +1,18 @@
+Having multiple relaxed default bounds is unsupported.
+
+Erroneous code example:
+
+```compile_fail,E0203
+struct Bad<T: ?Sized + ?Send>{
+    inner: T
+}
+```
+
+Here the type `T` cannot have a relaxed bound for multiple default traits
+(`Sized` and `Send`). This can be fixed by only using one relaxed bound.
+
+```
+struct Good<T: ?Sized>{
+    inner: T
+}
+```