diff --git a/src/tools/moc/ppkeywords.cpp b/src/tools/moc/ppkeywords.cpp
index dc13f3db95d..8931f7b5c0b 100644
--- a/src/tools/moc/ppkeywords.cpp
+++ b/src/tools/moc/ppkeywords.cpp
@@ -5,18 +5,18 @@
 // DO NOT EDIT.
 
 static const short pp_keyword_trans[][128] = {
-    {0,0,0,0,0,0,0,0,0,98,12,0,0,0,0,0,
+    {0,0,0,0,0,0,0,0,0,111,13,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
-     98,76,96,13,1,60,62,97,9,10,58,56,11,57,102,59,
-     6,6,6,6,6,6,6,6,6,6,92,0,7,81,8,91,
+     111,89,109,14,1,73,75,110,10,11,71,69,12,70,115,72,
+     7,7,7,7,7,7,7,7,7,7,105,0,8,94,9,104,
      0,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
-     1,1,1,1,1,1,1,1,1,1,1,0,101,0,61,1,
+     1,1,1,1,1,1,1,1,1,1,1,0,114,0,74,6,
      0,1,2,3,4,1,1,1,1,1,1,1,1,1,5,1,
-     1,1,1,1,1,1,1,1,1,1,1,0,68,0,71,0},
+     1,1,1,1,1,1,1,1,1,1,1,0,81,0,84,0},
     {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
-     0,0,0,0,0,0,0,0,0,0,0,0,79,87,0,0,
+     0,0,0,0,0,0,0,0,0,0,0,0,92,100,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
@@ -24,26 +24,26 @@ static const short pp_keyword_trans[][128] = {
     {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
-     0,0,0,0,0,0,0,0,0,0,0,0,0,88,80,0,
+     0,0,0,0,0,0,0,0,0,0,0,0,0,101,93,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0},
     {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
-     0,0,0,93,0,0,0,0,0,0,0,0,0,0,0,0,
+     0,0,0,106,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
-     0,0,0,0,14,34,0,0,0,20,0,0,0,0,0,0,
-     0,0,0,0,0,22,0,0,0,0,0,0,0,0,0,0},
+     0,0,0,0,15,35,0,0,0,21,0,0,0,0,0,0,
+     0,0,0,0,0,23,0,0,0,0,0,0,0,0,0,0},
     {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
-     0,0,0,0,0,0,21,0,0,0,0,0,0,0,44,0,
+     0,0,0,0,0,0,22,0,0,0,0,0,0,0,45,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0},
     {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
@@ -51,7 +51,7 @@ static const short pp_keyword_trans[][128] = {
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
-     0,0,0,0,27,0,0,0,0,0,0,0,0,0,30,0,
+     0,0,0,0,28,0,0,0,0,0,0,0,0,0,31,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0},
     {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
@@ -59,7 +59,7 @@ static const short pp_keyword_trans[][128] = {
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
-     0,0,0,0,0,0,0,0,0,0,0,0,35,0,40,0,
+     0,0,0,0,0,0,0,0,0,0,0,0,36,0,41,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0},
     {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
@@ -67,11 +67,11 @@ static const short pp_keyword_trans[][128] = {
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
-     0,0,0,0,0,0,0,0,0,36,0,0,0,0,0,0,
-     0,0,0,38,0,0,0,0,0,0,0,0,0,0,0,0},
+     0,0,0,0,0,0,0,0,0,37,0,0,0,0,0,0,
+     0,0,0,39,0,0,0,0,0,0,0,0,0,0,0,0},
     {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
-     0,0,0,0,0,0,0,0,0,0,100,0,0,0,0,99,
+     0,0,0,0,0,0,0,0,0,0,113,0,0,0,0,112,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
@@ -83,12 +83,12 @@ static const short pp_keyword_trans[][128] = {
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
-     0,65,0,0,0,0,0,0,0,0,0,0,0,0,0,69,
+     0,78,0,0,0,0,0,0,0,0,0,0,0,0,0,82,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0},
     {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
-     103,103,103,103,103,103,103,103,103,103,0,0,0,0,0,0,
+     116,116,116,116,116,116,116,116,116,116,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
      0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
@@ -105,10 +105,11 @@ static const struct
 } pp_keywords[] = {
     {PP_NOTOKEN, 0, 0, 0, PP_NOTOKEN},
     {PP_CHARACTER, 0, 0, 0, PP_NOTOKEN},
-    {PP_CHARACTER, 0, 105, 63, PP_NOTOKEN},
-    {PP_CHARACTER, 0, 111, 72, PP_NOTOKEN},
-    {PP_CHARACTER, 0, 101, 50, PP_NOTOKEN},
-    {PP_CHARACTER, 0, 111, 77, PP_NOTOKEN},
+    {PP_CHARACTER, 0, 105, 76, PP_NOTOKEN},
+    {PP_CHARACTER, 0, 111, 85, PP_NOTOKEN},
+    {PP_CHARACTER, 0, 101, 63, PP_NOTOKEN},
+    {PP_CHARACTER, 0, 111, 90, PP_NOTOKEN},
+    {PP_CHARACTER, 0, 95, 51, PP_NOTOKEN},
     {PP_DIGIT, 0, 0, 0, PP_NOTOKEN},
     {PP_LANGLE, 1, 0, 0, PP_NOTOKEN},
     {PP_RANGLE, 2, 0, 0, PP_NOTOKEN},
@@ -117,78 +118,90 @@ static const struct
     {PP_COMMA, 0, 0, 0, PP_NOTOKEN},
     {PP_NEWLINE, 0, 0, 0, PP_NOTOKEN},
     {PP_HASH, 3, 0, 0, PP_HASH},
-    {PP_HASH, 0, 101, 15, PP_HASH},
-    {PP_HASH, 0, 102, 16, PP_HASH},
-    {PP_HASH, 0, 105, 17, PP_HASH},
-    {PP_HASH, 0, 110, 18, PP_HASH},
-    {PP_HASH, 0, 101, 19, PP_HASH},
+    {PP_HASH, 0, 101, 16, PP_HASH},
+    {PP_HASH, 0, 102, 17, PP_HASH},
+    {PP_HASH, 0, 105, 18, PP_HASH},
+    {PP_HASH, 0, 110, 19, PP_HASH},
+    {PP_HASH, 0, 101, 20, PP_HASH},
     {PP_DEFINE, 0, 0, 0, PP_HASH},
     {PP_HASH, 4, 0, 0, PP_HASH},
     {PP_IF, 5, 0, 0, PP_HASH},
-    {PP_HASH, 0, 110, 23, PP_HASH},
-    {PP_HASH, 0, 100, 24, PP_HASH},
-    {PP_HASH, 0, 101, 25, PP_HASH},
-    {PP_HASH, 0, 102, 26, PP_HASH},
+    {PP_HASH, 0, 110, 24, PP_HASH},
+    {PP_HASH, 0, 100, 25, PP_HASH},
+    {PP_HASH, 0, 101, 26, PP_HASH},
+    {PP_HASH, 0, 102, 27, PP_HASH},
     {PP_UNDEF, 0, 0, 0, PP_HASH},
-    {PP_HASH, 0, 101, 28, PP_HASH},
-    {PP_HASH, 0, 102, 29, PP_HASH},
+    {PP_HASH, 0, 101, 29, PP_HASH},
+    {PP_HASH, 0, 102, 30, PP_HASH},
     {PP_IFDEF, 0, 0, 0, PP_HASH},
-    {PP_HASH, 0, 100, 31, PP_HASH},
-    {PP_HASH, 0, 101, 32, PP_HASH},
-    {PP_HASH, 0, 102, 33, PP_HASH},
+    {PP_HASH, 0, 100, 32, PP_HASH},
+    {PP_HASH, 0, 101, 33, PP_HASH},
+    {PP_HASH, 0, 102, 34, PP_HASH},
     {PP_IFNDEF, 0, 0, 0, PP_HASH},
     {PP_HASH, 6, 0, 0, PP_HASH},
     {PP_HASH, 7, 0, 0, PP_HASH},
-    {PP_HASH, 0, 102, 37, PP_HASH},
+    {PP_HASH, 0, 102, 38, PP_HASH},
     {PP_ELIF, 0, 0, 0, PP_HASH},
-    {PP_HASH, 0, 101, 39, PP_HASH},
+    {PP_HASH, 0, 101, 40, PP_HASH},
     {PP_ELSE, 0, 0, 0, PP_HASH},
-    {PP_HASH, 0, 100, 41, PP_HASH},
-    {PP_HASH, 0, 105, 42, PP_HASH},
-    {PP_HASH, 0, 102, 43, PP_HASH},
+    {PP_HASH, 0, 100, 42, PP_HASH},
+    {PP_HASH, 0, 105, 43, PP_HASH},
+    {PP_HASH, 0, 102, 44, PP_HASH},
     {PP_ENDIF, 0, 0, 0, PP_HASH},
-    {PP_HASH, 0, 99, 45, PP_HASH},
-    {PP_HASH, 0, 108, 46, PP_HASH},
-    {PP_HASH, 0, 117, 47, PP_HASH},
-    {PP_HASH, 0, 100, 48, PP_HASH},
-    {PP_HASH, 0, 101, 49, PP_HASH},
+    {PP_HASH, 0, 99, 46, PP_HASH},
+    {PP_HASH, 0, 108, 47, PP_HASH},
+    {PP_HASH, 0, 117, 48, PP_HASH},
+    {PP_HASH, 0, 100, 49, PP_HASH},
+    {PP_HASH, 0, 101, 50, PP_HASH},
     {PP_INCLUDE, 0, 0, 0, PP_HASH},
-    {PP_CHARACTER, 0, 102, 51, PP_CHARACTER},
-    {PP_CHARACTER, 0, 105, 52, PP_CHARACTER},
-    {PP_CHARACTER, 0, 110, 53, PP_CHARACTER},
-    {PP_CHARACTER, 0, 101, 54, PP_CHARACTER},
-    {PP_CHARACTER, 0, 100, 55, PP_CHARACTER},
+    {PP_CHARACTER, 0, 104, 52, PP_CHARACTER},
+    {PP_CHARACTER, 0, 97, 53, PP_CHARACTER},
+    {PP_CHARACTER, 0, 115, 54, PP_CHARACTER},
+    {PP_CHARACTER, 0, 95, 55, PP_CHARACTER},
+    {PP_CHARACTER, 0, 105, 56, PP_CHARACTER},
+    {PP_CHARACTER, 0, 110, 57, PP_CHARACTER},
+    {PP_CHARACTER, 0, 99, 58, PP_CHARACTER},
+    {PP_CHARACTER, 0, 108, 59, PP_CHARACTER},
+    {PP_CHARACTER, 0, 117, 60, PP_CHARACTER},
+    {PP_CHARACTER, 0, 100, 61, PP_CHARACTER},
+    {PP_CHARACTER, 0, 101, 62, PP_CHARACTER},
+    {PP_HAS_INCLUDE, 0, 0, 0, PP_CHARACTER},
+    {PP_CHARACTER, 0, 102, 64, PP_CHARACTER},
+    {PP_CHARACTER, 0, 105, 65, PP_CHARACTER},
+    {PP_CHARACTER, 0, 110, 66, PP_CHARACTER},
+    {PP_CHARACTER, 0, 101, 67, PP_CHARACTER},
+    {PP_CHARACTER, 0, 100, 68, PP_CHARACTER},
     {PP_DEFINED, 0, 0, 0, PP_CHARACTER},
     {PP_PLUS, 0, 0, 0, PP_NOTOKEN},
     {PP_MINUS, 0, 0, 0, PP_NOTOKEN},
     {PP_STAR, 0, 0, 0, PP_NOTOKEN},
     {PP_SLASH, 8, 0, 0, PP_NOTOKEN},
-    {PP_PERCENT, 0, 58, 94, PP_NOTOKEN},
+    {PP_PERCENT, 0, 58, 107, PP_NOTOKEN},
     {PP_HAT, 0, 0, 0, PP_NOTOKEN},
-    {PP_AND, 0, 38, 89, PP_NOTOKEN},
-    {PP_CHARACTER, 0, 116, 64, PP_CHARACTER},
+    {PP_AND, 0, 38, 102, PP_NOTOKEN},
+    {PP_CHARACTER, 0, 116, 77, PP_CHARACTER},
     {PP_CHARACTER, 9, 0, 0, PP_CHARACTER},
-    {PP_CHARACTER, 0, 110, 66, PP_CHARACTER},
-    {PP_CHARACTER, 0, 100, 67, PP_CHARACTER},
+    {PP_CHARACTER, 0, 110, 79, PP_CHARACTER},
+    {PP_CHARACTER, 0, 100, 80, PP_CHARACTER},
     {PP_AND, 0, 0, 0, PP_CHARACTER},
-    {PP_OR, 0, 124, 90, PP_NOTOKEN},
-    {PP_CHARACTER, 0, 114, 70, PP_CHARACTER},
+    {PP_OR, 0, 124, 103, PP_NOTOKEN},
+    {PP_CHARACTER, 0, 114, 83, PP_CHARACTER},
     {PP_OR, 0, 0, 0, PP_CHARACTER},
     {PP_TILDE, 0, 0, 0, PP_NOTOKEN},
-    {PP_CHARACTER, 0, 109, 73, PP_CHARACTER},
-    {PP_CHARACTER, 0, 112, 74, PP_CHARACTER},
-    {PP_CHARACTER, 0, 108, 75, PP_CHARACTER},
+    {PP_CHARACTER, 0, 109, 86, PP_CHARACTER},
+    {PP_CHARACTER, 0, 112, 87, PP_CHARACTER},
+    {PP_CHARACTER, 0, 108, 88, PP_CHARACTER},
     {PP_TILDE, 0, 0, 0, PP_CHARACTER},
-    {PP_NOT, 0, 61, 83, PP_NOTOKEN},
-    {PP_CHARACTER, 0, 116, 78, PP_CHARACTER},
-    {PP_NOT, 0, 95, 84, PP_CHARACTER},
+    {PP_NOT, 0, 61, 96, PP_NOTOKEN},
+    {PP_CHARACTER, 0, 116, 91, PP_CHARACTER},
+    {PP_NOT, 0, 95, 97, PP_CHARACTER},
     {PP_LTLT, 0, 0, 0, PP_NOTOKEN},
     {PP_GTGT, 0, 0, 0, PP_NOTOKEN},
-    {PP_INCOMPLETE, 0, 61, 82, PP_NOTOKEN},
+    {PP_INCOMPLETE, 0, 61, 95, PP_NOTOKEN},
     {PP_EQEQ, 0, 0, 0, PP_NOTOKEN},
     {PP_NE, 0, 0, 0, PP_NOTOKEN},
-    {PP_CHARACTER, 0, 101, 85, PP_CHARACTER},
-    {PP_CHARACTER, 0, 113, 86, PP_CHARACTER},
+    {PP_CHARACTER, 0, 101, 98, PP_CHARACTER},
+    {PP_CHARACTER, 0, 113, 99, PP_CHARACTER},
     {PP_NE, 0, 0, 0, PP_CHARACTER},
     {PP_LE, 0, 0, 0, PP_NOTOKEN},
     {PP_GE, 0, 0, 0, PP_NOTOKEN},
@@ -197,8 +210,8 @@ static const struct
     {PP_QUESTION, 0, 0, 0, PP_NOTOKEN},
     {PP_COLON, 0, 0, 0, PP_NOTOKEN},
     {PP_HASHHASH, 0, 0, 0, PP_NOTOKEN},
-    {PP_INCOMPLETE, 0, 37, 95, PP_NOTOKEN},
-    {PP_INCOMPLETE, 0, 58, 93, PP_NOTOKEN},
+    {PP_INCOMPLETE, 0, 37, 108, PP_NOTOKEN},
+    {PP_INCOMPLETE, 0, 58, 106, PP_NOTOKEN},
     {PP_QUOTE, 0, 0, 0, PP_NOTOKEN},
     {PP_SINGLEQUOTE, 0, 0, 0, PP_NOTOKEN},
     {PP_WHITESPACE, 0, 0, 0, PP_NOTOKEN},
diff --git a/src/tools/moc/preprocessor.cpp b/src/tools/moc/preprocessor.cpp
index 11ea8d417e2..721ee2bf519 100644
--- a/src/tools/moc/preprocessor.cpp
+++ b/src/tools/moc/preprocessor.cpp
@@ -706,17 +706,57 @@ void Preprocessor::substituteUntilNewline(Symbols &substituted)
             macroExpand(&substituted, this, symbols, index, symbol().lineNum, true);
         } else if (token == PP_DEFINED) {
             bool braces = test(PP_LPAREN);
-            next(PP_IDENTIFIER);
-            Symbol definedOrNotDefined = symbol();
-            definedOrNotDefined.token = macros.contains(definedOrNotDefined)? PP_MOC_TRUE : PP_MOC_FALSE;
-            substituted += definedOrNotDefined;
+            if (test(PP_HAS_INCLUDE)) {
+                // __has_include is always supported
+                Symbol definedOrNotDefined = symbol();
+                definedOrNotDefined.token = PP_MOC_TRUE;
+                substituted += definedOrNotDefined;
+            } else {
+                next(PP_IDENTIFIER);
+                Symbol definedOrNotDefined = symbol();
+                definedOrNotDefined.token = macros.contains(definedOrNotDefined)? PP_MOC_TRUE : PP_MOC_FALSE;
+                substituted += definedOrNotDefined;
+            }
             if (braces)
                 test(PP_RPAREN);
             continue;
         } else if (token == PP_NEWLINE) {
             substituted += symbol();
             break;
-        } else {
+        } else if (token == PP_HAS_INCLUDE) {
+            next(LPAREN);
+            Token tok = next(); // quote or LANGLE
+            bool usesAngleInclude = false;
+            QByteArray includeAsString;
+            Symbols innerSymbols;
+            if (tok == PP_LANGLE) {
+                usesAngleInclude = true;
+                next();
+                do {
+                    Symbol currentSymbol  = symbol();
+                    includeAsString += currentSymbol.lexem();
+                    if (currentSymbol.token == PP_IDENTIFIER)
+                        macroExpand(&innerSymbols, this, symbols, index, symbol().lineNum, true);
+                    else
+                        innerSymbols.append(currentSymbol);
+                } while (next() != PP_RANGLE);
+            } else {
+                includeAsString = unquotedLexem();
+            }
+            next(RPAREN);
+            const QByteArray &relative  = usesAngleInclude ? QByteArray() : currentFilenames.top();
+            bool result = !resolveInclude(includeAsString, relative).isNull();
+            if (usesAngleInclude && !result) {
+                // try with expansion
+                includeAsString = {};
+                for (const auto &innerSymbol: innerSymbols)
+                    includeAsString.append(innerSymbol.lexem());
+                result = !resolveInclude(includeAsString, relative).isNull();
+            }
+            Symbol definedOrNotDefined = symbol();
+            definedOrNotDefined.token = result ? PP_MOC_TRUE : PP_MOC_FALSE;
+            substituted += definedOrNotDefined;
+        } else  {
             substituted += symbol();
         }
     }
diff --git a/src/tools/moc/token.h b/src/tools/moc/token.h
index 95ef385a797..e07ff56892d 100644
--- a/src/tools/moc/token.h
+++ b/src/tools/moc/token.h
@@ -186,6 +186,7 @@ QT_BEGIN_NAMESPACE
     F(PP_ELSE) \
     F(PP_ENDIF) \
     F(PP_INCLUDE) \
+    F(PP_HAS_INCLUDE) \
     F(PP_HASHHASH) \
     F(PP_HASH) \
     F(PP_DEFINED) \
diff --git a/src/tools/moc/util/generate_keywords.cpp b/src/tools/moc/util/generate_keywords.cpp
index b98914d7177..76e6707fe69 100644
--- a/src/tools/moc/util/generate_keywords.cpp
+++ b/src/tools/moc/util/generate_keywords.cpp
@@ -1,4 +1,4 @@
-// Copyright (C) 2016 The Qt Company Ltd.
+// Copyright (C) 2016 TheQt Company Ltd.
 // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only WITH Qt-GPL-exception-1.0
 #include <stdio.h>
 #include <string.h>
@@ -27,6 +27,7 @@ static const Keyword pp_keywords[] = {
     { "#else", "PP_ELSE"},
     { "#endif", "PP_ENDIF"},
     { "#include", "PP_INCLUDE"},
+    { "__has_include", "PP_HAS_INCLUDE"},
     { "defined", "PP_DEFINED"},
     { "+", "PP_PLUS" },
     { "-", "PP_MINUS" },
diff --git a/tests/auto/tools/moc/tst_moc.cpp b/tests/auto/tools/moc/tst_moc.cpp
index 42846cdfe5c..9c345093854 100644
--- a/tests/auto/tools/moc/tst_moc.cpp
+++ b/tests/auto/tools/moc/tst_moc.cpp
@@ -785,6 +785,7 @@ private slots:
     void initTestCase();
 
     void dontStripNamespaces();
+    void hasIncludeSupport();
     void oldStyleCasts();
     void faultyQmlRegistration_data();
     void faultyQmlRegistration();
@@ -943,6 +944,18 @@ private:
     } while (false)
 
 
+#ifdef __has_include
+class HasIncludeTest {
+    Q_GADGET
+#  if __has_include(<vector>)
+    Q_INVOKABLE void couldFindVector() {}
+#  endif
+#  if __has_include("using-namespaces.h")
+    Q_INVOKABLE void couldFindLocal() {}
+#  endif
+};
+#endif
+
 void tst_Moc::initTestCase()
 {
     QString binpath = QLibraryInfo::path(QLibraryInfo::BinariesPath);
@@ -976,6 +989,14 @@ void tst_Moc::initTestCase()
     QVERIFY(TestPointeeCanBeIncomplete::staticMetaObject.className());
 }
 
+void tst_Moc::hasIncludeSupport()
+{
+    auto hasIncludeTestMo = &HasIncludeTest::staticMetaObject;
+    QVERIFY(hasIncludeTestMo->className());
+    QVERIFY(hasIncludeTestMo->indexOfMethod("couldFindVector()") != -1);
+    QVERIFY(hasIncludeTestMo->indexOfMethod("couldFindLocal()") != -1);
+}
+
 void tst_Moc::dontStripNamespaces()
 {
     Sender sender;