[Metadata] Define _objc_empty_cache under SWIF_OBJC_INTEROP.

Davide Italiano · Davide Italiano · commit a59d82188f0d · 2018-03-04T12:29:09.000-08:00
Later code uses the variable under this macro, so defining it
under NDEBUG breaks debug builds of stdlib.
diff --git a/stdlib/public/runtime/Metadata.cpp b/stdlib/public/runtime/Metadata.cpp
@@ -226,7 +226,7 @@ static GenericMetadataCache &unsafeGetInitializedCache(
   return lazyCache->unsafeGetAlreadyInitialized();
 }
 
-#ifndef NDEBUG
+#if SWIFT_OBJC_INTEROP
 extern "C" void *_objc_empty_cache;
 #endif
 

Original file line number	Diff line number	Diff line change
`@@ -226,7 +226,7 @@ static GenericMetadataCache &unsafeGetInitializedCache(`
`226`	`226`	`return lazyCache->unsafeGetAlreadyInitialized();`
`227`	`227`	`}`
`228`	`228`
`229`		`-#ifndef NDEBUG`
	`229`	`+#if SWIFT_OBJC_INTEROP`
`230`	`230`	`extern "C" void *_objc_empty_cache;`
`231`	`231`	`#endif`
`232`	`232`