---

yaml
---
r: 343481
b: refs/heads/master-rebranch
c: 6b1f0c9
h: refs/heads/master
i:
  343479: cf684a0

Author: theblixguy

[refs]

@@ -1455,7 +1455,7 @@ refs/tags/swift-DEVELOPMENT-SNAPSHOT-2019-08-02-a: ddd2b2976aa9bfde5f20fe37f6bd2
 refs/tags/swift-DEVELOPMENT-SNAPSHOT-2019-08-03-a: 171cc166f2abeb5ca2a4003700a8a78a108bd300
 refs/heads/benlangmuir-patch-1: baaebaf39d52f3bf36710d4fe40cf212e996b212
 refs/heads/i-do-redeclare: 8c4e6d5de5c1e3f0a2cedccf319df713ea22c48e
-refs/heads/master-rebranch: 8c3cb7111a60141b73e976c194aec0983775ec3d
+refs/heads/master-rebranch: 6b1f0c9bae7f9f788afc2740e3db581c421a90c2
 refs/heads/rdar-53901732: 9bd06af3284e18a109cdbf9aa59d833b24eeca7b
 refs/heads/revert-26776-subst-always-returns-a-type: 1b8e18fdd391903a348970a4c848995d4cdd789c
 refs/heads/tensorflow-merge: 8b854f62f80d4476cb383d43c4aac2001dde3cec

branches/master-rebranch/lib/Sema/TypeCheckProtocol.cpp

@@ -2072,10 +2072,9 @@ diagnoseMatch(ModuleDecl *module, NormalProtocolConformance *conformance,
                    (unsigned)match.MissingRequirement->getKind());
     break;
 
-  case MatchKind::ThrowsConflict: {
+  case MatchKind::ThrowsConflict:
     diags.diagnose(match.Witness, diag::protocol_witness_throws_conflict);
     break;
-  }
 
   case MatchKind::OptionalityConflict: {
     auto &adjustments = match.OptionalAdjustments;
@@ -2146,24 +2145,20 @@ diagnoseMatch(ModuleDecl *module, NormalProtocolConformance *conformance,
     }
     break;
   }
-  case MatchKind::MutatingConflict: {
+  case MatchKind::MutatingConflict:
     diags.diagnose(match.Witness,
                    diag::protocol_witness_mutation_modifier_conflict,
                    SelfAccessKind::Mutating);
     break;
-  }
-  case MatchKind::NonMutatingConflict: {
-    diags.diagnose(match.Witness,
-                   diag::protocol_witness_mutation_modifier_conflict,
-                   SelfAccessKind::NonMutating);
+  case MatchKind::NonMutatingConflict:
+    // Don't bother about this, because a non-mutating witness can satisfy
+    // a mutating requirement.
     break;
-  }
-  case MatchKind::ConsumingConflict: {
+  case MatchKind::ConsumingConflict:
     diags.diagnose(match.Witness,
                    diag::protocol_witness_mutation_modifier_conflict,
                    SelfAccessKind::Consuming);
     break;
-  }
   case MatchKind::RethrowsConflict: {
     auto witness = match.Witness;
     auto diag =