From 9a2efd9db7becdcb5c55f9abc6c70b835a5352be Mon Sep 17 00:00:00 2001
From: Bert Belder <bertbelder@gmail.com>
Date: Thu, 6 Sep 2018 19:53:13 +0200
Subject: [PATCH] nt: squelch novelty GCC 8 cast-function-type warnings

---
 src/nt.c | 22 ++++++++++++++++++----
 1 file changed, 18 insertions(+), 4 deletions(-)

diff --git a/src/nt.c b/src/nt.c
index 2b5fd44..408d0d4 100644
--- a/src/nt.c
+++ b/src/nt.c
@@ -3,6 +3,18 @@
 #include "nt.h"
 #include "win.h"
 
+/* Set up a workaround for the following problem:
+ *   FARPROC addr = GetProcAddress(...);
+ *   MY_FUNC func = (MY_FUNC) addr;          <-- GCC 8 warning/error.
+ *   MY_FUNC func = (MY_FUNC) (void*) addr;  <-- MSVC  warning/error.
+ * To compile cleanly with either compiler, do casts with this "bridge" type:
+ *   MY_FUNC func = (MY_FUNC) (nt__fn_ptr_cast_t) addr; */
+#ifdef __GNUC__
+typedef void* nt__fn_ptr_cast_t;
+#else
+typedef FARPROC nt__fn_ptr_cast_t;
+#endif
+
 #define X(return_type, attributes, name, parameters) \
   WEPOLL_INTERNAL return_type(attributes* name) parameters = NULL;
 NT_NTDLL_IMPORT_LIST(X)
@@ -10,15 +22,17 @@ NT_NTDLL_IMPORT_LIST(X)
 
 int nt_global_init(void) {
   HMODULE ntdll;
+  FARPROC fn_ptr;
 
   ntdll = GetModuleHandleW(L"ntdll.dll");
   if (ntdll == NULL)
     return -1;
 
-#define X(return_type, attributes, name, parameters)                         \
-  name = (return_type(attributes*) parameters) GetProcAddress(ntdll, #name); \
-  if (name == NULL)                                                          \
-    return -1;
+#define X(return_type, attributes, name, parameters) \
+  fn_ptr = GetProcAddress(ntdll, #name);             \
+  if (fn_ptr == NULL)                                \
+    return -1;                                       \
+  name = (return_type(attributes*) parameters)(nt__fn_ptr_cast_t) fn_ptr;
   NT_NTDLL_IMPORT_LIST(X)
 #undef X