Add workaround for unexpected libclang behaviour

`clang_tokenize(tu, clang_getCursorExtent(cursor), ...)` doesn't seem
to work properly when cursor points to expanded macro:
the result includes too many tokens

backend.native/tests/build.gradle

@@ -2733,6 +2733,10 @@ kotlinNativeInterop {
         defFile 'interop/basics/cmacros.def'
     }
 
+    cunsupported {
+        defFile 'interop/basics/cunsupported.def'
+    }
+
     if (isMac()) {
         objcSmoke {
             defFile 'interop/objc/objcSmoke.def'
@@ -2820,6 +2824,12 @@ task interop_macros(type: RunInteropKonanTest) {
     interop = 'cmacros'
 }
 
+task interop_unsupported(type: RunInteropKonanTest) {
+    disabled = (project.testTarget == 'wasm32') // No interop for wasm yet.
+    source = "interop/basics/unsupported.kt"
+    interop = 'cunsupported'
+}
+
 task interop_echo_server(type: RunInteropKonanTest) {
     disabled = (project.testTarget == 'wasm32') // No interop for wasm yet.
     if (!isMac()) {

backend.native/tests/interop/basics/cunsupported.def

@@ -0,0 +1,27 @@
+compilerOpts = -mno-xsave
+
+---
+
+static void noAttr() {}
+__attribute__((always_inline)) noTargetAttr() {}
+
+__attribute__((always_inline, __target__("xsave"))) void plainAttrs1() {}
+__attribute__((__target__("xsave"), always_inline)) void plainAttrs2() {}
+
+#define TARGET __target__
+
+__attribute__((always_inline, TARGET("xsave"))) void macroAttr1() {}
+__attribute__((TARGET("xsave"), always_inline)) void macroAttr2() {}
+
+#define TARGET_ATTR __target__("xsave")
+
+__attribute__((TARGET_ATTR, always_inline)) void macroAttr3() {}
+__attribute__((always_inline, TARGET_ATTR)) void macroAttr4() {}
+
+#define ALL_ATTRS1 __attribute__((always_inline, __target__("xsave")))
+
+ALL_ATTRS1 void macroAttr5() {}
+
+#define ALL_ATTRS2 __attribute__((always_inline, __target__("xsave")))
+
+ALL_ATTRS2 void macroAttr6() {}

backend.native/tests/interop/basics/unsupported.kt

@@ -0,0 +1,12 @@
+/*
+ * Copyright 2010-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
+ * that can be found in the LICENSE file.
+ */
+
+import kotlin.test.*
+import cunsupported.*
+
+fun main(args: Array<String>) {
+    noAttr()
+    noTargetAttr()
+}