diff --git a/coroutine/win32/Context.h b/coroutine/win32/Context.h
index 243ae5a43b..c1c8fbcd13 100644
--- a/coroutine/win32/Context.h
+++ b/coroutine/win32/Context.h
@@ -16,6 +16,7 @@
 #include <string.h>
 
 #define COROUTINE __declspec(noreturn) void __fastcall
+#define COROUTINE_DECL void __fastcall
 #define COROUTINE_LIMITED_ADDRESS_SPACE
 
 /* This doesn't include thread information block */
diff --git a/coroutine/win64/Context.h b/coroutine/win64/Context.h
index c5cab729f8..23b21b5c1c 100644
--- a/coroutine/win64/Context.h
+++ b/coroutine/win64/Context.h
@@ -16,6 +16,7 @@
 #include <string.h>
 
 #define COROUTINE __declspec(noreturn) void
+#define COROUTINE_DECL void
 
 enum {
     COROUTINE_REGISTERS = 8,