rtasm: fix void * / func * casting warnings

src/gallium/auxiliary/rtasm/rtasm_x86sse.c

@@ -1743,20 +1743,35 @@ void x86_release_func( struct x86_function *p )
 }
 
 
-void (*x86_get_func( struct x86_function *p ))(void)
+static INLINE x86_func
+voidptr_to_x86_func(void *v)
+{
+   union {
+      void *v;
+      x86_func f;
+   } u;
+   assert(sizeof(u.v) == sizeof(u.f));
+   u.v = v;
+   return u.f;
+}
+
+
+x86_func x86_get_func( struct x86_function *p )
 {
    DUMP_END();
    if (DISASSEM && p->store)
       debug_printf("disassemble %p %p\n", p->store, p->csr);
 
    if (p->store == p->error_overflow)
-      return (void (*)(void)) NULL;
+      return voidptr_to_x86_func(NULL);
    else
-      return (void (*)(void)) p->store;
+      return voidptr_to_x86_func(p->store);
 }
 
 #else
 
+void x86sse_dummy( void );
+
 void x86sse_dummy( void )
 {
 }

src/gallium/auxiliary/rtasm/rtasm_x86sse.h

@@ -102,6 +102,11 @@ enum sse_cc {
 #define cc_Z  cc_E
 #define cc_NZ cc_NE
 
+
+/** generic pointer to function */
+typedef void (*x86_func)(void);
+
+
 /* Begin/end/retrieve function creation:
  */
 
@@ -109,7 +114,7 @@ enum sse_cc {
 void x86_init_func( struct x86_function *p );
 void x86_init_func_size( struct x86_function *p, unsigned code_size );
 void x86_release_func( struct x86_function *p );
-void (*x86_get_func( struct x86_function *p ))( void );
+x86_func x86_get_func( struct x86_function *p );
 
 /* Debugging:
  */