Index: docs/ClangFormatStyleOptions.rst
===================================================================
--- docs/ClangFormatStyleOptions.rst	(revision 190620)
+++ docs/ClangFormatStyleOptions.rst	(working copy)
@@ -249,6 +249,9 @@
   If ``true``, spaces will be inserted between 'for'/'if'/'while'/...
   and '('.
 
+**SpaceBeforeAssignmentOperators** (``bool``)
+  If ``false``, spaces will be removed before '=', '+=', etc.
+
 **SpaceInEmptyParentheses** (``bool``)
   If ``false``, spaces may be inserted into '()'.
 
Index: include/clang/Format/Format.h
===================================================================
--- include/clang/Format/Format.h	(revision 190620)
+++ include/clang/Format/Format.h	(working copy)
@@ -222,6 +222,9 @@
   /// and '('.
   bool SpaceAfterControlStatementKeyword;
 
+  /// \brief If \c false, spaces will be removed before assignment operators.
+  bool SpaceBeforeAssignmentOperators;
+
   bool operator==(const FormatStyle &R) const {
     return AccessModifierOffset == R.AccessModifierOffset &&
            ConstructorInitializerIndentWidth ==
@@ -265,7 +268,9 @@
            SpacesInCStyleCastParentheses ==
                R.SpacesInCStyleCastParentheses &&
            SpaceAfterControlStatementKeyword ==
-               R.SpaceAfterControlStatementKeyword;
+               R.SpaceAfterControlStatementKeyword &&
+		   SpaceBeforeAssignmentOperators ==
+		       R.SpaceBeforeAssignmentOperators;
   }
 };
 
Index: lib/Format/Format.cpp
===================================================================
--- lib/Format/Format.cpp	(revision 190620)
+++ lib/Format/Format.cpp	(working copy)
@@ -147,6 +147,8 @@
                    Style.SpacesInCStyleCastParentheses);
     IO.mapOptional("SpaceAfterControlStatementKeyword",
                    Style.SpaceAfterControlStatementKeyword);
+    IO.mapOptional("SpaceBeforeAssignmentOperators",
+                   Style.SpaceBeforeAssignmentOperators);
   }
 };
 }
@@ -197,6 +199,7 @@
   LLVMStyle.SpaceInEmptyParentheses = false;
   LLVMStyle.SpacesInCStyleCastParentheses = false;
   LLVMStyle.SpaceAfterControlStatementKeyword = true;
+  LLVMStyle.SpaceBeforeAssignmentOperators = true;
 
   setDefaultPenalties(LLVMStyle);
   LLVMStyle.PenaltyReturnTypeOnItsOwnLine = 60;
@@ -239,6 +242,7 @@
   GoogleStyle.SpaceInEmptyParentheses = false;
   GoogleStyle.SpacesInCStyleCastParentheses = false;
   GoogleStyle.SpaceAfterControlStatementKeyword = true;
+  GoogleStyle.SpaceBeforeAssignmentOperators = true;
 
   setDefaultPenalties(GoogleStyle);
   GoogleStyle.PenaltyReturnTypeOnItsOwnLine = 200;
Index: lib/Format/TokenAnnotator.cpp
===================================================================
--- lib/Format/TokenAnnotator.cpp	(revision 190620)
+++ lib/Format/TokenAnnotator.cpp	(working copy)
@@ -1334,6 +1334,9 @@
   if (Tok.isOneOf(tok::arrowstar, tok::periodstar) ||
       Tok.Previous->isOneOf(tok::arrowstar, tok::periodstar))
     return false;
+  if (!Style.SpaceBeforeAssignmentOperators &&
+	  Tok.getPrecedence() == prec::Assignment)	
+    return false;
   if ((Tok.Type == TT_BinaryOperator && !Tok.Previous->is(tok::l_paren)) ||
       Tok.Previous->Type == TT_BinaryOperator)
     return true;
Index: unittests/Format/FormatTest.cpp
===================================================================
--- unittests/Format/FormatTest.cpp	(revision 190620)
+++ unittests/Format/FormatTest.cpp	(working copy)
@@ -5909,6 +5909,19 @@
                "}", Spaces);
 }
 
+TEST_F(FormatTest, ConfigurableSpaceBeforeAssignmentOperators) {
+  FormatStyle Spaces = getLLVMStyle();
+  
+  verifyFormat("int a = 5;", Spaces);
+  verifyFormat("a += 42;", Spaces);
+  verifyFormat("a or_eq 8;", Spaces);
+
+  Spaces.SpaceBeforeAssignmentOperators = false;
+  verifyFormat("int a= 5;", Spaces);
+  verifyFormat("a+= 42;", Spaces);
+  verifyFormat("a or_eq 8;", Spaces);
+}
+
 TEST_F(FormatTest, LinuxBraceBreaking) {
   FormatStyle BreakBeforeBrace = getLLVMStyle();
   BreakBeforeBrace.BreakBeforeBraces = FormatStyle::BS_Linux;
@@ -6150,6 +6163,7 @@
   CHECK_PARSE_BOOL(SpaceInEmptyParentheses);
   CHECK_PARSE_BOOL(SpacesInCStyleCastParentheses);
   CHECK_PARSE_BOOL(SpaceAfterControlStatementKeyword);
+  CHECK_PARSE_BOOL(SpaceBeforeAssignmentOperators);
 
   CHECK_PARSE("AccessModifierOffset: -1234", AccessModifierOffset, -1234);
   CHECK_PARSE("ConstructorInitializerIndentWidth: 1234",