diff --git a/ide/buildmanager.pas b/ide/buildmanager.pas
index dae0dc47e6..eff57d63e5 100644
--- a/ide/buildmanager.pas
+++ b/ide/buildmanager.pas
@@ -67,6 +67,8 @@ type
                                 var Abort: boolean): string;
     function MacroFuncTargetOS(const Param: string; const Data: PtrInt;
                                var Abort: boolean): string;
+    function MacroFuncSrcOS(const Param: string; const Data: PtrInt;
+                            var Abort: boolean): string;
     function MacroFuncFPCVer(const Param: string; const Data: PtrInt;
                              var Abort: boolean): string;
     function MacroFuncParams(const Param: string; const Data: PtrInt;
@@ -231,6 +233,8 @@ begin
                     lisTargetCPU,@MacroFuncTargetCPU,[]));
   GlobalMacroList.Add(TTransferMacro.Create('TargetOS','',
                     lisTargetOS,@MacroFuncTargetOS,[]));
+  GlobalMacroList.Add(TTransferMacro.Create('SrcOS','',
+                    lisSrcOS,@MacroFuncSrcOS,[]));
   GlobalMacroList.Add(TTransferMacro.Create('FPCVer','',
                     lisFPCVersionEG222, @MacroFuncFPCVer, []));
   GlobalMacroList.Add(TTransferMacro.Create('Params','',
@@ -1089,6 +1093,15 @@ begin
     Result:=GetTargetOS(true);
 end;
 
+function TBuildManager.MacroFuncSrcOS(const Param: string; const Data: PtrInt;
+  var Abort: boolean): string;
+begin
+  if Data=CompilerOptionMacroPlatformIndependent then
+    Result:='%(OS_TARGET)'
+  else
+    Result:=GetDefaultSrcOSForTargetOS(GetTargetOS(true));
+end;
+
 function TBuildManager.MacroFuncFPCVer(const Param: string; const Data: PtrInt;
   var Abort: boolean): string;
 var
diff --git a/ide/lazarusidestrconsts.pas b/ide/lazarusidestrconsts.pas
index 01e5759ce5..403ed1a47f 100644
--- a/ide/lazarusidestrconsts.pas
+++ b/ide/lazarusidestrconsts.pas
@@ -101,6 +101,7 @@ resourcestring
   lisCOVarious = '%s (various)';
   lisTargetCPU = 'Target CPU';
   lisTargetOS = 'Target OS';
+  lisSrcOS = 'Src OS';
   lisCommandLineParamsOfProgram = 'Command line parameters of program';
   lisPromptForValue = 'Prompt for value';
   lisProjectFilename = 'Project filename';
diff --git a/ide/startlazarus.lpi b/ide/startlazarus.lpi
index 2f137888ec..121b3878be 100644
--- a/ide/startlazarus.lpi
+++ b/ide/startlazarus.lpi
@@ -53,7 +53,7 @@
       <Filename Value="../startlazarus$(ExeExt)"/>
     </Target>
     <SearchPaths>
-      <IncludeFiles Value="include/$(TargetOS)/;include/$(SrcOS)/"/>
+      <IncludeFiles Value="include/;include/$(TargetOS)/;include/$(SrcOS)/"/>
       <OtherUnitFiles Value="../designer/;../packager/;../components/codetools/units/$(TargetCPU)-$(TargetOS)/"/>
       <UnitOutputDirectory Value="../units/$(TargetCPU)-$(TargetOS)"/>
     </SearchPaths>