diff --git a/lib/SIL/IR/AbstractionPattern.cpp b/lib/SIL/IR/AbstractionPattern.cpp
index 59fe0da628ed0..e7913e3b735ca 100644
--- a/lib/SIL/IR/AbstractionPattern.cpp
+++ b/lib/SIL/IR/AbstractionPattern.cpp
@@ -1366,7 +1366,14 @@ AbstractionPattern::getFunctionThrownErrorType(
     if (!substErrorType)
       return std::nullopt;
 
-    return std::make_pair(AbstractionPattern(*substErrorType),
+    // FIXME: This is actually unsound. The most opaque form of
+    // `(T) throws(U) -> V` should actually be
+    // `(T) throws(any Error) -> V`.
+    auto pattern = ((*substErrorType)->isErrorExistentialType()
+                    ? AbstractionPattern(*substErrorType)
+                    : AbstractionPattern::getOpaque());
+
+    return std::make_pair(pattern,
                           (*substErrorType)->getCanonicalType());
   }
 
diff --git a/test/SILGen/keypath_typed_throws.swift b/test/SILGen/keypath_typed_throws.swift
new file mode 100644
index 0000000000000..4fc9e02be99b5
--- /dev/null
+++ b/test/SILGen/keypath_typed_throws.swift
@@ -0,0 +1,8 @@
+// RUN: %target-swift-emit-silgen %s
+// RUN: %target-swift-emit-silgen %s -enable-library-evolution
+// RUN: %target-swift-emit-silgen %s -enable-testing
+// RUN: %target-swift-emit-silgen %s -enable-library-evolution -enable-testing
+
+public struct Visitor<Node, Failure: Error> {
+  public var visit: (Node) throws(Failure) -> Void
+}