Index: clang/lib/Format/UnwrappedLineParser.cpp
===================================================================
--- clang/lib/Format/UnwrappedLineParser.cpp
+++ clang/lib/Format/UnwrappedLineParser.cpp
@@ -539,7 +539,7 @@
       break;
     case tok::r_brace:
       if (OpeningBrace) {
-        if (!Style.RemoveBracesLLVM ||
+        if (!Style.RemoveBracesLLVM || Line->InPPDirective ||
             !OpeningBrace->isOneOf(TT_ControlStatementLBrace, TT_ElseLBrace)) {
           return false;
         }
Index: clang/unittests/Format/FormatTest.cpp
===================================================================
--- clang/unittests/Format/FormatTest.cpp
+++ clang/unittests/Format/FormatTest.cpp
@@ -25803,6 +25803,13 @@
 
   Style.ColumnLimit = 20;
 
+  verifyFormat("int i;\n"
+               "#define FOO(a, b)  \\\n"
+               "  while (a) {      \\\n"
+               "    b;             \\\n"
+               "  }",
+               Style);
+
   verifyFormat("int ab = [](int i) {\n"
                "  if (i > 0) {\n"
                "    i = 12345678 -\n"