CryptoPkg SysCall Lib: Fix warning with GCC in CrtWrapper.c

Exit is declared to be 'noreturn' function, but GCC sees
that the empty function will return.  Therefore, GCC flags
a warning.

To work-around this, we use a function pointer, along with
a cast to force the code to think that a 'noreturn' function
is being called.

Signed-off-by: jljusten
Reviewed-by: qlong

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@11609 6f19259b-4bc3-4df7-8a09-765794883524

CryptoPkg/Library/BaseCryptLib/SysCall/CrtWrapper.c

@@ -330,11 +330,42 @@ void closelog (void)
 
 }
 
+#ifdef __GNUC__
+
+typedef
+VOID
+(EFIAPI *NoReturnFuncPtr)(
+  VOID
+  ) __attribute__((__noreturn__));
+
+
+STATIC
+VOID
+EFIAPI
+NopFunction (
+  VOID
+  )
+{
+}
+
+
 void exit (int e)
 {
+  NoReturnFuncPtr NoReturnFunc;
 
+  NoReturnFunc = (NoReturnFuncPtr) NopFunction;
+
+  NoReturnFunc ();
 }
 
+#else
+
+void exit (int e)
+{
+}
+
+#endif
+
 int fclose (FILE *f)
 {
   return 0;