diff --git a/clang/lib/Sema/SemaOverload.cpp b/clang/lib/Sema/SemaOverload.cpp
--- a/clang/lib/Sema/SemaOverload.cpp
+++ b/clang/lib/Sema/SemaOverload.cpp
@@ -3346,7 +3346,10 @@
     bool Usable = !Info.Constructor->isInvalidDecl() &&
                   S.isInitListConstructor(Info.Constructor);
     if (Usable) {
-      bool SuppressUserConversions = false;
+      // If the first argument is (a reference to) the target type,
+      // suppress conversions.
+      bool SuppressUserConversions = isFirstArgumentCompatibleWithType(
+          S.Context, Info.Constructor, ToType);
       if (Info.ConstructorTmpl)
         S.AddTemplateOverloadCandidate(Info.ConstructorTmpl, Info.FoundDecl,
                                        /*ExplicitArgs*/ nullptr, From,
@@ -3470,18 +3473,14 @@
                                  /*AllowExplicit*/ true);
         if (Usable) {
           bool SuppressUserConversions = !ConstructorsOnly;
-          // C++20 [over.best.ics.general]/4.5:
-          //   if the target is the first parameter of a constructor [of class
-          //   X] and the constructor [...] is a candidate by [...] the second
-          //   phase of [over.match.list] when the initializer list has exactly
-          //   one element that is itself an initializer list, [...] and the
-          //   conversion is to X or reference to cv X, user-defined conversion
-          //   sequences are not cnosidered.
           if (SuppressUserConversions && ListInitializing) {
-            SuppressUserConversions =
-                NumArgs == 1 && isa<InitListExpr>(Args[0]) &&
-                isFirstArgumentCompatibleWithType(S.Context, Info.Constructor,
-                                                  ToType);
+            SuppressUserConversions = false;
+            if (NumArgs == 1) {
+              // If the first argument is (a reference to) the target type,
+              // suppress conversions.
+              SuppressUserConversions = isFirstArgumentCompatibleWithType(
+                  S.Context, Info.Constructor, ToType);
+            }
           }
           if (Info.ConstructorTmpl)
             S.AddTemplateOverloadCandidate(
diff --git a/clang/test/CXX/drs/dr14xx.cpp b/clang/test/CXX/drs/dr14xx.cpp
--- a/clang/test/CXX/drs/dr14xx.cpp
+++ b/clang/test/CXX/drs/dr14xx.cpp
@@ -296,9 +296,6 @@
 } // std
 
 namespace dr1467 {  // dr1467: 3.7 c++11
-  // Note that the change to [over.best.ics] was partially undone by DR2076;
-  // the resulting rule is tested with the tests for that change.
-
   // List-initialization of aggregate from same-type object
 
   namespace basic0 {
@@ -422,7 +419,7 @@
     void f() { Value{{{1,2},{3,4}}}; }
   }
   namespace NonAmbiguous {
-  // The original implementation made this case ambiguous due to the special
+  // The original implementation made this case ambigious due to the special
   // handling of one element initialization lists.
   void f(int(&&)[1]);
   void f(unsigned(&&)[1]);
diff --git a/clang/test/CXX/drs/dr20xx.cpp b/clang/test/CXX/drs/dr20xx.cpp
--- a/clang/test/CXX/drs/dr20xx.cpp
+++ b/clang/test/CXX/drs/dr20xx.cpp
@@ -49,47 +49,6 @@
   }
 }
 
-namespace dr2076 { // dr2076: 13
-#if __cplusplus >= 201103L
-  namespace std_example {
-    struct A { A(int); };
-    struct B { B(A); };
-    B b{{0}};
-
-    struct Params { int a; int b; };
-    struct Foo {
-      Foo(Params);
-    };
-    Foo foo{{1, 2}};
-  }
-
-  struct string_view {
-    string_view(int); // not an aggregate
-  };
-  struct string {
-    string(int); // not an aggregate
-    operator string_view() const;
-  };
-
-  void foo(const string &); // expected-note {{cannot convert initializer list}}
-  void bar(string_view); // expected-note 2{{cannot convert initializer list}}
-
-  void func(const string &arg) {
-    // An argument in one set of braces is subject to user-defined conversions;
-    // an argument in two sets of braces is not, but an identity conversion is
-    // still OK.
-    foo(arg);
-    foo({arg});
-    foo({{arg}});
-    foo({{{arg}}}); // expected-error {{no matching function}}
-    bar(arg);
-    bar({arg});
-    bar({{arg}}); // expected-error {{no matching function}}
-    bar({{{arg}}}); // expected-error {{no matching function}}
-  }
-#endif
-}
-
 namespace dr2082 { // dr2082: 11
   void test1(int x, int = sizeof(x)); // ok
 #if __cplusplus >= 201103L
diff --git a/libcxx/utils/ci/buildkite-pipeline.yml b/libcxx/utils/ci/buildkite-pipeline.yml
--- a/libcxx/utils/ci/buildkite-pipeline.yml
+++ b/libcxx/utils/ci/buildkite-pipeline.yml
@@ -18,294 +18,6 @@
 #
 
 steps:
-  #
-  # Light pre-commit tests for things like formatting or when people forget
-  # to update generated files.
-  #
-  - label: "Format"
-    command: "libcxx/utils/ci/run-buildbot check-format"
-    artifact_paths:
-      - "**/clang-format.patch"
-    agents:
-      queue: "libcxx-builders"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    soft_fail:
-        - exit_status: 1
-
-  - label: "Generated output"
-    command: "libcxx/utils/ci/run-buildbot check-generated-output"
-    artifact_paths:
-      - "**/generated_output.patch"
-    agents:
-      queue: "libcxx-builders"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  #
-  # General testing with the default configuration, under all the supported
-  # Standard modes, with Clang and GCC. This catches most issues upfront.
-  # The goal of this step is to catch most issues while being very fast.
-  #
-  - wait
-
-  - label: "C++03"
-    command: "libcxx/utils/ci/run-buildbot generic-cxx03"
-    artifact_paths:
-      - "**/test-results.xml"
-      - "**/*.abilist"
-    agents:
-      queue: "libcxx-builders"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  - label: "C++11"
-    command: "libcxx/utils/ci/run-buildbot generic-cxx11"
-    artifact_paths:
-      - "**/test-results.xml"
-      - "**/*.abilist"
-    agents:
-      queue: "libcxx-builders"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  - label: "C++14"
-    command: "libcxx/utils/ci/run-buildbot generic-cxx14"
-    artifact_paths:
-      - "**/test-results.xml"
-      - "**/*.abilist"
-    agents:
-      queue: "libcxx-builders"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  - label: "C++17"
-    command: "libcxx/utils/ci/run-buildbot generic-cxx17"
-    artifact_paths:
-      - "**/test-results.xml"
-      - "**/*.abilist"
-    agents:
-      queue: "libcxx-builders"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  - label: "C++20"
-    command: "libcxx/utils/ci/run-buildbot generic-cxx20"
-    artifact_paths:
-      - "**/test-results.xml"
-      - "**/*.abilist"
-    agents:
-      queue: "libcxx-builders"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  - label: "C++2b"
-    command: "libcxx/utils/ci/run-buildbot generic-cxx2b"
-    artifact_paths:
-      - "**/test-results.xml"
-      - "**/*.abilist"
-    agents:
-      queue: "libcxx-builders"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  - label: "GCC/C++20"
-    command: "libcxx/utils/ci/run-buildbot generic-gcc"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  #
-  # All other supported configurations of libc++.
-  #
-  - wait
-
-  - label: "-fno-exceptions"
-    command: "libcxx/utils/ci/run-buildbot generic-noexceptions"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  - label: "Static libraries"
-    command: "libcxx/utils/ci/run-buildbot generic-static"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  - label: "ASAN"
-    command: "libcxx/utils/ci/run-buildbot generic-asan"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  - label: "TSAN"
-    command: "libcxx/utils/ci/run-buildbot generic-tsan"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  - label: "UBSAN"
-    command: "libcxx/utils/ci/run-buildbot generic-ubsan"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  - label: "With LLVM's libunwind"
-    command: "libcxx/utils/ci/run-buildbot generic-with_llvm_unwinder"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  - label: "Single-threaded"
-    command: "libcxx/utils/ci/run-buildbot generic-singlethreaded"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  - label: "No debug mode"
-    command: "libcxx/utils/ci/run-buildbot generic-no-debug"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  - label: "No Filesystem"
-    command: "libcxx/utils/ci/run-buildbot generic-no-filesystem"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  - label: "No random device"
-    command: "libcxx/utils/ci/run-buildbot generic-no-random_device"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  - label: "No locale"
-    command: "libcxx/utils/ci/run-buildbot generic-no-localization"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  - label: "Benchmarks"
-    command: "libcxx/utils/ci/run-buildbot benchmarks"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  - label: "Documentation"
-    command: "libcxx/utils/ci/run-buildbot documentation"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  - label: "Legacy standalone build"
-    command: "libcxx/utils/ci/run-buildbot legacy-standalone"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  - label: "Unified standalone build"
-    command: "libcxx/utils/ci/run-buildbot unified-standalone"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
   - label: "Runtimes build"
     command: "libcxx/utils/ci/run-buildbot runtimes-build"
     artifact_paths:
@@ -316,146 +28,3 @@
       automatic:
         - exit_status: -1  # Agent was lost
           limit: 2
-
-  - label: "Windows"
-    # TODO: The CI runner doesn't have bash in the path currently. Once it
-    # has that, remove the absolute path and just call 'bash' here.
-    command: "\"\\Program Files\\Git\\usr\\bin\\bash\" libcxx/utils/ci/run-buildbot generic-win"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "windows"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  - label: "MacOS C++20"
-    command: "libcxx/utils/ci/run-buildbot generic-cxx20"
-    artifact_paths:
-      - "**/test-results.xml"
-      - "**/*.abilist"
-    agents:
-      queue: "libcxx-builders-macos"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  # Build with the configuration we use to generate libc++.dylib on Apple platforms
-  - label: "Apple system"
-    command: "libcxx/utils/ci/run-buildbot x86_64-apple-system"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders-macos"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  - label: "Apple system -fno-exceptions"
-    command: "libcxx/utils/ci/run-buildbot x86_64-apple-system-noexceptions"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders-macos"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  # Test back-deployment to older Apple platforms
-  - label: "Apple back-deployment macosx10.9"
-    command: "libcxx/utils/ci/run-buildbot x86_64-apple-system-backdeployment-10.9"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders-macos10.15" # TODO: For now, we're running the back-deployment tests for 10.9 on 10.15, because we don't have proper 10.9 machines
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  - label: "Apple back-deployment macosx10.15"
-    command: "libcxx/utils/ci/run-buildbot x86_64-apple-system-backdeployment-10.15"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders-macos10.15"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  - label: "AArch64"
-    command: "libcxx/utils/ci/run-buildbot aarch64"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders-linaro-arm"
-      arch: "aarch64"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  - label: "AArch64 -fno-exceptions"
-    command: "libcxx/utils/ci/run-buildbot aarch64-noexceptions"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders-linaro-arm"
-      arch: "aarch64"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  - label: "Armv8"
-    command: "libcxx/utils/ci/run-buildbot armv8"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders-linaro-arm"
-      arch: "armv8l"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  - label: "Armv8 -fno-exceptions"
-    command: "libcxx/utils/ci/run-buildbot armv8-noexceptions"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders-linaro-arm"
-      arch: "armv8l"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  - label: "Armv7"
-    command: "libcxx/utils/ci/run-buildbot armv7"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders-linaro-arm"
-      arch: "armv8l" # Compiling for v7, running on v8 hardware
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-
-  - label: "Armv7 -fno-exceptions"
-    command: "libcxx/utils/ci/run-buildbot armv7-noexceptions"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders-linaro-arm"
-      arch: "armv8l" # Compiling for v7, running on v8 hardware
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2