Index: include/clang/Format/Format.h
===================================================================
--- include/clang/Format/Format.h
+++ include/clang/Format/Format.h
@@ -1201,6 +1201,18 @@
   /// \endcode
   bool SpaceBeforeAssignmentOperators;
 
+  /// \brief If ``false``, spaces will be removed before colon.
+  /// This affects C++11 loop, initializer list, inheritance list and container
+  /// literals.
+  /// \code
+  ///    true:                                  false:
+  ///    class Foo : Bar {}             vs.     class Foo: Bar {}
+  ///    Foo::Foo() : a(a) {}                   Foo::Foo(): a(a) {}
+  ///    for (auto i : myList) {}               for (auto i: myList) {}
+  ///    f({a : 1, b : 2, c : 3});              f({a: 1, b: 2, c: 3});
+  /// \endcode
+  bool SpaceBeforeColon;
+
   /// \brief Different ways to put a space before opening parentheses.
   enum SpaceBeforeParensOptions {
     /// Never put a space before opening parentheses.
@@ -1414,6 +1426,7 @@
            SpaceAfterCStyleCast == R.SpaceAfterCStyleCast &&
            SpaceAfterTemplateKeyword == R.SpaceAfterTemplateKeyword &&
            SpaceBeforeAssignmentOperators == R.SpaceBeforeAssignmentOperators &&
+           SpaceBeforeColon == R.SpaceBeforeColon &&
            SpaceBeforeParens == R.SpaceBeforeParens &&
            SpaceInEmptyParentheses == R.SpaceInEmptyParentheses &&
            SpacesBeforeTrailingComments == R.SpacesBeforeTrailingComments &&
Index: lib/Format/Format.cpp
===================================================================
--- lib/Format/Format.cpp
+++ lib/Format/Format.cpp
@@ -346,6 +346,7 @@
     IO.mapOptional("SpaceAfterTemplateKeyword", Style.SpaceAfterTemplateKeyword);
     IO.mapOptional("SpaceBeforeAssignmentOperators",
                    Style.SpaceBeforeAssignmentOperators);
+    IO.mapOptional("SpaceBeforeColon", Style.SpaceBeforeColon);
     IO.mapOptional("SpaceBeforeParens", Style.SpaceBeforeParens);
     IO.mapOptional("SpaceInEmptyParentheses", Style.SpaceInEmptyParentheses);
     IO.mapOptional("SpacesBeforeTrailingComments",
@@ -565,6 +566,7 @@
   LLVMStyle.SpacesInCStyleCastParentheses = false;
   LLVMStyle.SpaceAfterCStyleCast = false;
   LLVMStyle.SpaceAfterTemplateKeyword = true;
+  LLVMStyle.SpaceBeforeColon = true;
   LLVMStyle.SpaceBeforeParens = FormatStyle::SBPO_ControlStatements;
   LLVMStyle.SpaceBeforeAssignmentOperators = true;
   LLVMStyle.SpacesInAngles = false;
Index: lib/Format/TokenAnnotator.cpp
===================================================================
--- lib/Format/TokenAnnotator.cpp
+++ lib/Format/TokenAnnotator.cpp
@@ -2341,8 +2341,10 @@
   if (Right.is(tok::comma))
     return false;
   if (Right.isOneOf(TT_CtorInitializerColon, TT_ObjCBlockLParen))
-    return true;
+    return Style.SpaceBeforeColon;
   if (Right.is(tok::colon)) {
+    if (!Style.SpaceBeforeColon && Right.isNot(TT_ConditionalExpr))
+      return false;
     if (Line.First->isOneOf(tok::kw_case, tok::kw_default) ||
         !Right.getNextNonComment() || Right.getNextNonComment()->is(tok::semi))
       return false;
Index: unittests/Format/FormatTest.cpp
===================================================================
--- unittests/Format/FormatTest.cpp
+++ unittests/Format/FormatTest.cpp
@@ -7519,6 +7519,20 @@
   verifyFormat("a or_eq 8;", Spaces);
 }
 
+TEST_F(FormatTest, ConfigurableSpaceBeforeColon) {
+  verifyFormat("class Foo : public Bar {};");
+  verifyFormat("Foo::Foo() : foo(1) {}");
+  verifyFormat("for (auto a : b) {\n}");
+  verifyFormat("int x = a ? b : c;");
+
+  FormatStyle Spaces = getLLVMStyle();
+  Spaces.SpaceBeforeColon = false;
+  verifyFormat("class Foo: public Bar {};", Spaces);
+  verifyFormat("Foo::Foo(): foo(1) {}", Spaces);
+  verifyFormat("for (auto a: b) {\n}", Spaces);
+  verifyFormat("int x = a ? b : c;", Spaces);
+}
+
 TEST_F(FormatTest, AlignConsecutiveAssignments) {
   FormatStyle Alignment = getLLVMStyle();
   Alignment.AlignConsecutiveAssignments = false;
@@ -8703,6 +8717,7 @@
   CHECK_PARSE_BOOL(SpaceAfterCStyleCast);
   CHECK_PARSE_BOOL(SpaceAfterTemplateKeyword);
   CHECK_PARSE_BOOL(SpaceBeforeAssignmentOperators);
+  CHECK_PARSE_BOOL(SpaceBeforeColon);
 
   CHECK_PARSE_NESTED_BOOL(BraceWrapping, AfterClass);
   CHECK_PARSE_NESTED_BOOL(BraceWrapping, AfterControlStatement);