[Frontend] -Isystem doesn't work everywhere -I does

ian-twilightcoder · ian-twilightcoder · commit a1d10ed6e73b · 2025-06-02T15:06:32.000-07:00
We missed a spot where we need to pass -Isystem along with -I.

rdar://152267441
diff --git a/lib/Driver/ToolChains.cpp b/lib/Driver/ToolChains.cpp
@@ -261,7 +261,7 @@ void ToolChain::addCommonFrontendArgs(const OutputInfo &OI,
     arguments.push_back("-color-diagnostics");
   }
 
-  inputArgs.AddAllArgs(arguments, options::OPT_I);
+  inputArgs.addAllArgs(arguments, {options::OPT_I, options::OPT_Isystem});
   inputArgs.addAllArgs(arguments, {options::OPT_F, options::OPT_Fsystem});
   inputArgs.AddAllArgs(arguments, options::OPT_vfsoverlay);
 

Original file line number	Diff line number	Diff line change
`@@ -261,7 +261,7 @@ void ToolChain::addCommonFrontendArgs(const OutputInfo &OI,`
`261`	`261`	`arguments.push_back("-color-diagnostics");`
`262`	`262`	`}`
`263`	`263`
`264`		`- inputArgs.AddAllArgs(arguments, options::OPT_I);`
	`264`	`+ inputArgs.addAllArgs(arguments, {options::OPT_I, options::OPT_Isystem});`
`265`	`265`	`inputArgs.addAllArgs(arguments, {options::OPT_F, options::OPT_Fsystem});`
`266`	`266`	`inputArgs.AddAllArgs(arguments, options::OPT_vfsoverlay);`
`267`	`267`