fix some possible errors

Origin commit data
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Branch: ni/coolstream
Commit: d5d6c4de62
Author: Jacek Jendrzej <overx300@gmail.com>
Date: 2014-11-06 (Thu, 06 Nov 2014)


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No further description and justification available within origin commit message!

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This commit was generated by Migit

src/system/helpers.cpp

@@ -124,6 +124,7 @@ int my_system(int argc, const char *arg, ...)
 		if (i == argv_max)
 		{
 			fprintf(stderr, "my_system: too many arguments!\n");
+			va_end(args);
 			return -1;
 		}
 		argv[i] = va_arg(args, const char *);