diff --git a/clang/lib/Format/ContinuationIndenter.cpp b/clang/lib/Format/ContinuationIndenter.cpp
--- a/clang/lib/Format/ContinuationIndenter.cpp
+++ b/clang/lib/Format/ContinuationIndenter.cpp
@@ -1682,8 +1682,12 @@
         (State.Line->Type != LT_ObjCDecl && Style.BinPackParameters) ||
         (State.Line->Type == LT_ObjCDecl && ObjCBinPackProtocolList);
 
+    bool GenericSelection =
+        Current.getPreviousNonComment() &&
+        Current.getPreviousNonComment()->is(tok::kw__Generic);
+
     AvoidBinPacking =
-        (CurrentState.IsCSharpGenericTypeConstraint) ||
+        (CurrentState.IsCSharpGenericTypeConstraint) || GenericSelection ||
         (Style.isJavaScript() && EndsInComma) ||
         (State.Line->MustBeDeclaration && !BinPackDeclaration) ||
         (!State.Line->MustBeDeclaration && !Style.BinPackArguments) ||
diff --git a/clang/lib/Format/FormatToken.h b/clang/lib/Format/FormatToken.h
--- a/clang/lib/Format/FormatToken.h
+++ b/clang/lib/Format/FormatToken.h
@@ -70,6 +70,8 @@
   TYPE(FunctionLBrace)                                                         \
   TYPE(FunctionLikeOrFreestandingMacro)                                        \
   TYPE(FunctionTypeLParen)                                                     \
+  /* The colons as part of a C11 _Generic selection */                         \
+  TYPE(GenericSelectionColon)                                                  \
   /* The colon at the end of a goto label or a case label. Currently only used \
    * for Verilog. */                                                           \
   TYPE(GotoLabelColon)                                                         \
diff --git a/clang/lib/Format/TokenAnnotator.cpp b/clang/lib/Format/TokenAnnotator.cpp
--- a/clang/lib/Format/TokenAnnotator.cpp
+++ b/clang/lib/Format/TokenAnnotator.cpp
@@ -321,6 +321,10 @@
     } else if (isLambdaParameterList(&OpeningParen)) {
       // This is a parameter list of a lambda expression.
       Contexts.back().IsExpression = false;
+    } else if (OpeningParen.Previous &&
+               OpeningParen.Previous->is(tok::kw__Generic)) {
+      Contexts.back().ContextType = Context::C11GenericSelection;
+      Contexts.back().IsExpression = true;
     } else if (Line.InPPDirective &&
                (!OpeningParen.Previous ||
                 !OpeningParen.Previous->is(tok::identifier))) {
@@ -1026,6 +1030,8 @@
         }
       } else if (Contexts.back().ColonIsForRangeExpr) {
         Tok->setType(TT_RangeBasedForLoopColon);
+      } else if (Contexts.back().ContextType == Context::C11GenericSelection) {
+        Tok->setType(TT_GenericSelectionColon);
       } else if (CurrentToken && CurrentToken->is(tok::numeric_constant)) {
         Tok->setType(TT_BitFieldColon);
       } else if (Contexts.size() == 1 &&
@@ -1621,6 +1627,8 @@
       StructArrayInitializer,
       // Like in `static_cast<int>`.
       TemplateArgument,
+      // C11 _Generic selection
+      C11GenericSelection,
     } ContextType = Unknown;
   };
 
@@ -4170,6 +4178,8 @@
       return false;
     if (Right.is(TT_CSharpNamedArgumentColon))
       return false;
+    if (Right.is(TT_GenericSelectionColon))
+      return false;
     if (Right.is(TT_BitFieldColon)) {
       return Style.BitFieldColonSpacing == FormatStyle::BFCS_Both ||
              Style.BitFieldColonSpacing == FormatStyle::BFCS_Before;
diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -22909,6 +22909,18 @@
   verifyFormat("x = (_Atomic( uint64_t ))&a;", Style);
 }
 
+TEST_F(FormatTest, C11Generic) {
+  verifyFormat("_Generic(x, int: 1, default: 0)");
+  verifyFormat("#define cbrt(X) _Generic((X), float: cbrtf, default: cbrt)(X)");
+  verifyFormat("_Generic(x,\n"
+               "         float: f,\n"
+               "         default: d,\n"
+               "         long double: ld,\n"
+               "         float _Complex: fc,\n"
+               "         double _Complex: dc,\n"
+               "         long double _Complex: ldc)");
+}
+
 TEST_F(FormatTest, AmbersandInLamda) {
   // Test case reported in https://bugs.llvm.org/show_bug.cgi?id=41899
   FormatStyle AlignStyle = getLLVMStyle();
diff --git a/clang/unittests/Format/TokenAnnotatorTest.cpp b/clang/unittests/Format/TokenAnnotatorTest.cpp
--- a/clang/unittests/Format/TokenAnnotatorTest.cpp
+++ b/clang/unittests/Format/TokenAnnotatorTest.cpp
@@ -1105,6 +1105,14 @@
   EXPECT_TOKEN(Tokens[1], tok::identifier, TT_FunctionDeclarationName);
 }
 
+TEST_F(TokenAnnotatorTest, UnderstandsC11GenericSelection) {
+  auto Tokens = annotate("_Generic(x, int: 1, default: 0)");
+  ASSERT_EQ(Tokens.size(), 13u) << Tokens;
+  EXPECT_TOKEN(Tokens[0], tok::kw__Generic, TT_Unknown);
+  EXPECT_TOKEN(Tokens[5], tok::colon, TT_GenericSelectionColon);
+  EXPECT_TOKEN(Tokens[9], tok::colon, TT_GenericSelectionColon);
+}
+
 TEST_F(TokenAnnotatorTest, UnderstandsVerilogOperators) {
   auto Annotate = [this](llvm::StringRef Code) {
     return annotate(Code, getLLVMStyle(FormatStyle::LK_Verilog));